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Sample records for chisels

  1. Chiseled Gold Ornament

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    According to some archaeological discoveries, people began to use gold to make ornaments during the Shang Dynasty, more than 3,000 years ago. This partfcular piece of chiseled gold ornament was unearthed in 1957 from the Ming Dynasty tomb of Wang Gui at You’anmen, Beijing. Wang Gui was a head of the Imperial Bodyguard in the Ming Dynasty. His eldest daughter was an imperial concubine of the Emperor Cheng Hua. Consequently, his family held a prominent position at the time. The gold ornament, 50.5 centimeters in length and 295 grams in weight, is composed of two parts. The upper part is shaped like lotus leaves, with fine double lines as the vein. To indicate auspiciousness, a pair of mandarin ducks with lotus flowers in their months sit on either side of the thick leaves. Seven long gold chains measuring 21 centimeters in length link the

  2. Chisels in the italian Bronze Age: technological and typological aspects

    OpenAIRE

    Speciale, Claudia; Zanini, Alessandro

    2010-01-01

    Bronze chisels are tools used “à percussion posée”; this means they need a minimum length and some functional parts (tang, body, blade); they could have a handle of perishable material and they were used with a hammer to work wood, bronze and other materials. Chisels can be classified following their functional parts; the first element is the shape (rod or socketed chisel); the second one is body section; the third one is tang section. Chronology and distribution of every type were identified...

  3. Chisels in the italian Bronze Age: technological and typological aspects

    Directory of Open Access Journals (Sweden)

    Speciale, Claudia

    2010-12-01

    Full Text Available Bronze chisels are tools used “à percussion posée”; this means they need a minimum length and some functional parts (tang, body, blade; they could have a handle of perishable material and they were used with a hammer to work wood, bronze and other materials. Chisels can be classified following their functional parts; the first element is the shape (rod or socketed chisel; the second one is body section; the third one is tang section. Chronology and distribution of every type were identified to obtain a general view of this class of tools during the Italian Bronze Age.

    Los cinceles de bronce son herramientas que se utilizan en percusión apoyada (à percussion posée, por consiguiente, necesitan una longitud mínima y algunas partes funcionales (empuñadura, cuerpo, hoja; podrían tener un mango de material perecedero. Se utilizan con un martillo en el labrado de la madera, del bronce y de otros materiales. Los cinceles se pueden clasificar de acuerdo con los siguientes elementos funcionales: el primero es la forma (cincel de varilla o de cubo; el segundo es la sección del cuerpo; el tercero es la sección de la empuñadura. La cronología y la distribución de cada tipo se identificaron para obtener una visión general de esta clase de instrumentos durante la Edad del Bronce en Italia.

  4. Temporary effect of chiseling on the compaction of a Rhodic Hapludox under no-tillage

    Directory of Open Access Journals (Sweden)

    Sâmala Glícia Carneiro Silva

    2012-04-01

    Full Text Available Mechanical chiseling has been used to alleviate the effects of compaction in soils under no-tillage (NT. However, its effect on the soil physical properties does not seem to have a defined duration period. The purpose of this study was to evaluate the behavior of the bulk density (BD and degree of compaction (DC at different soil depths, after chiseling in no-tillage, for one year. The experiment was performed in Ponta Grossa, Paraná State, Brazil, using an Oxisol (Rhodic Hapludox. Bulk density and DC were previously measured in an area under NT for 16 years, then immediately after chiseling (CHI in May 2009, six months after chiseling (CHI6M in October 2009 and one year after chiseling (CHI12M in May 2010. In the layers 0.0-0.10, 0.10-0.20 and 0.20-0.30 m, there was a significant BD reduction CHI and a marked increase CHI6M. The BD values measured CHI12M were similar to those before tillage. Chiseling reduced the DC in the layers 0.0-0.10 m and 0.10-0.20 m, but returned to the initial values one year later. During the evaluation periods CHI, CHI6M and CHI12M, the BD increased in the layer 0.30-0.40 m, compared with NT. The highest DC values were observed six months after chiseling; nevertheless the structural recovery of the soil was considerable, possibly due to the high degree of soil resilience and the influence of the wetting and drying cycles detected in the study period. The chiseling effects, evaluated by BD and DC, lasted less than one year, i.e., the beneficial short-term effects of chiseling on the reduction of the surface BD increased the risk of compaction in deeper soil layers.

  5. The terminal effects of chisel-shape projectile penetrating into metallic target plates

    Science.gov (United States)

    Tao, Xu; Yao, Xiaohu; Ma, Wei

    2015-09-01

    This work performs the analysis and simulation investigations of penetration behaviors of chisel-shape projectile. In analysis, the projectile is assumed to be a rigid body and the target plate is elastic-plastic material. By introducing the velocity potential function, the velocity field in target is first obtained. Then, the momentum equation is solved for determining the pressure and stress fields in the elastic and plastic regions in target. The variation of the resultant force subjected by the projectiles with the penetration depth is studied. The approximate expressions of penetration depth and the residual velocity with the initial impacting velocity are obtained for the exploration of the penetration mechanisms of the chisel-shape projectile. In numerical simulation, the main attention focuses on the dissipation mechanisms of the kinetic energy of the chisel-shape projectile in penetration process.

  6. DESIGN FEATURES OF THE NEW CHISEL COMBINED AND CALCULATION NEEDS OF THE ENGINE POWER AT HIS WORK

    Directory of Open Access Journals (Sweden)

    Maslov G. G.

    2015-05-01

    Full Text Available The article presents technologies and design features of the proposed chisel combined unit, combining in a single pass over the field 3 operations: deep loosening, crumbling additional topsoil and alignment, fertilizing. Design features of such a subsoiller as the basis of the unit include a chisel on each rack, fixed at an angle of 15-25 degrees to the horizontal and lessons along the center line of the rack feet, and flat cutting fun-leveling, consisting of two coaxially bred drums equipped with ripper teeth securely fastened according to our patents and placed in 5-9 rows on the surface of the drums on the helix, with rows of teeth on both drums have the opposite direction. The teeth of the first drum are long by 5-9 cm than the second, the clearance between the teeth of the first and second drum does not exceed 1.5 cm, and the ends of the teeth between the first reel and the cylindrical surface of the second - 1 cm. Front legs each provided with a divider soil laid down by its center and related to the lower of its parts - the bit. The first reel is mounted to 5 cm clearance between it and the cylindrical surface of the soil, which improves process reliability. We have got analytical dependences of the required power for the engine of the tractor unit with the proposed change of the working speed and width at the optimum utilization traction tractor plowing 0.9. We have justified a preferred brand of domestic and foreign tractors for this purpose

  7. Effect of Plowing Depth of Tillage and Forward Speed on the Performance of a Medium Size Chisel Plow Operating in a Sandy Soil

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    S. A. Al-Suhaibani

    2010-01-01

    Full Text Available Problem statement: Tillage is a process of creating a desirable soil condition for seed germination and growth. The tillage of soil is considered to be one of the biggest farm operations as the tillage operation requires the most energy on the farm. Chisel plow is widely used by farmers as a primary tillage tool. Performance data for chisel plow operation is essential in order to reduce the cost of tillage operation. Approach: Field experiments were conducted using a fully instrumented MS 3090 tractor to measure the draft of a heavy duty chisel plow in a sandy soil over wide ranges of plowing depths and forward speeds. The data were measured and recorded using an instrumentation system and data logger. Results: The effects of plowing depth and forward speeds on draft, unit draft, vertical specific draft, horizontal specific draft and coefficient of pull were evaluated. The results indicated that increasing the plowing depth and/or the forward speed increased the draft, unit draft and vertical specific draft. Also, increasing the plowing depth increased the horizontal specific draft and the coefficient of pull, while increasing the forward speed decreased the horizontal specific draft and the coefficient of pull. Conclusion: About 16.6% of the draft force was directed towards cutting the soil and 83.4% was consumed in pulverization of soil particles. The values of the vertical specific draft were much higher than those of the horizontal specific draft for all plowing depths and forward speeds. The plowing depth had more pronounced effect on the draft, unit draft, specific draft and coefficient of pull than the forward speed. The optimum forward speed was 1.75 m sec-1. The recommended plowing depth should be based on the type of crop (depth of the root system.

  8. ChISELS 1.0: theory and user manual :a theoretical modeler of deposition and etch processes in microsystems fabrication.

    Energy Technology Data Exchange (ETDEWEB)

    Plimpton, Steven James; Schmidt, Rodney Cannon; Ho, Pauline; Musson, Lawrence Cale

    2006-09-01

    Chemically Induced Surface Evolution with Level-Sets--ChISELS--is a parallel code for modeling 2D and 3D material depositions and etches at feature scales on patterned wafers at low pressures. Designed for efficient use on a variety of computer architectures ranging from single-processor workstations to advanced massively parallel computers running MPI, ChISELS is a platform on which to build and improve upon previous feature-scale modeling tools while taking advantage of the most recent advances in load balancing and scalable solution algorithms. Evolving interfaces are represented using the level-set method and the evolution equations time integrated using a Semi-Lagrangian approach [1]. The computational meshes used are quad-trees (2D) and oct-trees (3D), constructed such that grid refinement is localized to regions near the surface interfaces. As the interface evolves, the mesh is dynamically reconstructed as needed for the grid to remain fine only around the interface. For parallel computation, a domain decomposition scheme with dynamic load balancing is used to distribute the computational work across processors. A ballistic transport model is employed to solve for the fluxes incident on each of the surface elements. Surface chemistry is computed by either coupling to the CHEMKIN software [2] or by providing user defined subroutines. This report describes the theoretical underpinnings, methods, and practical use instruction of the ChISELS 1.0 computer code.

  9. Rugosidade superficial do solo formada por escarificação e influenciada pela erosividade da chuva Soil surface roughness formed by chiseling and affected by rainfall erosivity

    Directory of Open Access Journals (Sweden)

    Wilson Antonio Zoldan Junior

    2008-02-01

    do solo semeadura direta e preparo convencional.Surface soil roughness is affected by many factors, such as the residual effect of the soil management, tillage and rainfall erosivity and, together with the soil cover of crop residues, influences water erosion. The objective of this study was to determine the effects of a chiseling operation, together with rainfall erosivity, on soil surface roughness, from June 2005 to March 2006, in an aluminic Typical Hapludox, under the following soil management systems: bare soil under conventional tillage (BCT, cultivated soil under conventional tillage (CCT, no-tillage in a never-tilled soil with burnt plant residues (BNT, and traditional no-tillage (TNT. The crop sequence in the treatments CCT, BNT and TNT was black oat, soybean, common vetch, corn, black oat, common bean, fodder radish, soybean, common vetch, corn and black oat. Five simulated rain tests were applied, with a constant intensity of 64 mm h-1 and durations of 20, 30, 40, 50, and 60 min each. Natural rains during the experimental period accounted for 57 mm, between the 2nd and 3rd rainfall test; 21 mm, between the 3rd and 4th test; and, 30 mm, between the 4th and 5th test. The surface roughness was determined immediately before and immediately after the chiseling tillage, and immediately after each test of rain simulation. The original and linear soil surface roughness was not influenced by the management, unlike random roughness, at the end of a six-month fallow period. The original, linear and random roughness in different soil management systems was affected by a six-month fallow period, when the soil was subjected to chiseling. Random roughness was less influenced by soil slope than by tillage marks, which decreased with the increasing rainfall erosivity. The coefficient of decay of this kind of soil roughness was similar in the studied soil management systems under no tillage and conventional tillage.

  10. Porosidade de aeração de um Latossolo Vermelho e rendimento de trigo em plantio direto escarificado Air-filled porosity in Latosol and wheat grain yield under no-tillage chiseled

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    Vilson Antonio Klein

    2008-04-01

    Full Text Available Proporcionar condições ótimas ao desenvolvimento das plantas deve ser um dos objetivos do manejo do solo. O sistema plantio direto é um manejo conservacionista por excelência, mas tem apresentado problemas de compactação, afetando o desenvolvimento e à produtividade das culturas. A escarificação esporádica do solo nessas áreas tem-se apresentado como uma alternativa para minimizar os efeitos negativos do aumento da sua densidade. Neste estudo, avaliou-se a densidade do solo, a porosidade total e de aeração, a densidade máxima e a relativa do solo e o rendimento de grãos de trigo num Latossolo em duas áreas: plantio direto há 6 anos (PD e plantio direto escarificado (PDE. Durante todo o ciclo da cultura do trigo, monitorou-se o potencial de água no solo por meio de sensores eletrônicos e "datalogger". A escarificação esporádica do solo sob sistema plantio direto diminuiu (5% a densidade e a densidade relativa do solo, aumentou a porosidade total e alterou a dinâmica da água no solo, proporcionou maior volume de poros livres de água (7,6% durante todo o ciclo da cultura do trigo e aumentou significativamente o rendimento de grãos (682kg ha-1.The soil management should be aimed at providing optimal conditions for plant growth and development. No-tillage is a quintessential conservative system; however, it has caused compaction, thus affecting crop development and yield. Sporadic soil chiseling in these areas has been used as an alternative to minimize the negative effects of an increase in bulk density. The soil bulk density, total porosity, air-filled porosity, maximum density, relative density, and wheat grain yield of an oxisol were assessed in two areas: under no-tillage for 6 years and under no tillage chiseled. Soil water potential was monitored throughout the wheat crop cycle by using electronic sensors and a datalogger. Results show that sporadic chiseling of the soil under no-tillage reduced soil density and

  11. Escarificação em plantio direto como técnica de conservação do solo e da água Chiseling in no-tillage system as soil and water conservation practice

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    Rodrigo Kurylo Camara

    2005-10-01

    roughness, can affect water dynamics by reducing the water infiltration rate. Our aim was to evaluate changes in soil properties under NT and chiseling in no tillage (CNT, as well as the effect of distinct planter furrow openers on soil characteristics. The following parameters were assessed: bulk and particle density, total porosity, macroporosity, water infiltration into soil prior to soybean planting, surface roughness, percentage of soil surface covered with crop residues before and after planting, and soil hydraulic conductivity after 12 months of chiseling. CNT showed a lower soil density than NT, higher water infiltration, higher saturated soil hydraulic conductivity, and higher surface roughness. Therefore, CNT improved soil and water conservation since there were still residual effects one year after chiseling. Total porosity and macroporosity did not differ significantly between the soil management systems. Soil cover was similar under both managements before planting, i.e., six months after chiseling; however, at soybean planting, the hoe-type planter provided better incorporation of crop residues into the soil than the double-disc type.

  12. Painless minimally invasive surgery versus chisel osteotomy in the extraction of impacted mandibular third molars%无痛微创法与凿骨劈冠法拔除下颌阻生智齿的临床观察

    Institute of Scientific and Technical Information of China (English)

    李然; 唐小剑; 杨震; 朱正宏

    2012-01-01

    目的 观察无痛微创法和凿骨劈冠法拔除下颌阻生智齿的临床疗效.方法 306颗下颌阻生智齿随机分成2组,分别采用无痛微创法(实验组)和凿骨劈冠法(对照组)拔除患牙,记录2组平均拔除时间、术后肿胀、疼痛、张口受限、颞颌关节痛、干槽症等并发症发生情况及对拔牙的畏惧感.结果 实验组与对照组相比,平均拔除时间明显缩短(P<0.01);术后疼痛、肿胀、张口受限、颞颌关节痛、干槽症等并发症发生率较对照组明显降低(P<0.01);术前畏惧在术后的消失率和术前不畏惧在术后出现的畏惧率,均表明实验组优于对照组(P<0.001).结论 随着社会-心理-生物医学模式的不断完善,拔牙手术正由传统的凿骨劈冠法向着无痛、微创、安全、规范、舒适、愉悦等人性化方向发展.%Objective To compare the clinical effects of minimally invasive surgery ( MIS) with those of traditional chisel osteotomy in the extraction of impacted mandibular third molars. Methods We extracted 306 impacted mandibular third molars by MIS (experimental group) and traditional chisel osteotomy (control group) , respectively, and compared the two groups in the operation time, patients'fear of tooth extraction and postoperative complications, such as swelling, pain, limitation of mouth opening, sore temporoman-dibular joint and dry socket. Results Compared with the controls, the experimental group showed significantly shorter operation time, lower rates of pain, swelling, limitation of mouth opening, sore temporomandibular joint, dry socket, and less fear of tooth extraction (P <0. 01). Conclusions MIS is evidently superior over chisel osteotomy in the extraction of impacted mandibular third molars. With the development of the model of socio-psycho-bio-medicine, tooth extraction is assuming more humanized characteristics as pain-lessness, invasiveness, safety, comfort and normalization.

  13. Infiltração de água no solo sob escarificação e rotação de culturas Water infiltration in soil as influenced by chiseling and crop rotations

    Directory of Open Access Journals (Sweden)

    Maryara Buriola Prando

    2010-06-01

    Full Text Available Nos solos com restrições físicas e, ou, físico-hídricas ao crescimento de raízes, aumentar o potencial de armazenagem de água por meio de melhorias na infiltração pode ser uma estratégia viável para aumento da produtividade das culturas. Nesse sentido, este trabalho teve como objetivo avaliar a infiltração de água em um Nitossolo Vermelho distrófico, com três sistemas de rotação de culturas sob semeadura direta com e sem escarificação inicial. O sistema de rotação de culturas constou de: (1 milheto/soja/sorgo/milho/sorgo (M/S/So/Mi/So, (2 milheto/soja/Brachiaria ruziziensis/milho/Brachiaria ruziziensis (M/S/B/Mi/B e (3 milheto/soja/Brachiaria ruziziensis + mamona/milho/Brachiaria ruziziensis + mamona (M/S/B+Ma/Mi/B+Ma. A infiltração de água no solo foi avaliada em campo com anéis concêntricos instalados na superfície, a 0,10 e 0,20 m de profundidade, em 2006 e 2007. Após o primeiro ano, o manejo com escarificação inicial do solo apresentou a maior infiltração de água. A rotação Brachiaria ruziziensis + mamona proporcionou maior infiltração da água no solo. A atividade do sistema radicular das espécies nas parcelas sem escarificação inicial aumentou a velocidade de infiltração da água no solo.In soils with physical and/or physical hydric restrictions for root growth, it may be a viable strategy to increase crop productivity by increasing water storage potential through improvements in water infiltration. Accordingly, the objective of this study was to determine water infiltration in a Hapludult in three crop rotations under no-tillage, with and without initial chiseling. Crop rotations consisted of: millet/soybean/sorghum/maize/sorghum; millet/soybean/Brachiaria ruziziensis/corn/Brachiaria ruziziensis; and millet/soybean/Brachiaria ruziziensis + castor bean/corn/Brachiaria ruziziensis + castor bean. Water infiltration in soil was evaluated in the field, using concentric discs at the soil surface and at

  14. 高速涡轮气钻法与凿骨劈冠法在拔除下颌水平埋伏阻生智齿中的对比研究%Comparison of High-speed Air Turbine and Traditional Chisel Technique on Extracting Impacted Mandible Third Molars

    Institute of Scientific and Technical Information of China (English)

    林静; 卢保全; 陈永锋; 王英

    2013-01-01

    Objective:To compare the clinical effects of high -speed air turbine drill and traditional chisel on removal of impacted mandible third molars .Methods:The clinical datas of the patients with 120 lower impacted mandible third molar were retrospectively analyzed .In witch high-speed air drill group(60) and chisel group(60)to be performed tooth extraction by high -speed air drill and traditional chisel osteotomy respectively .Then the duration of extraction and the intraoperative and postoperative complications were observed and recorded to assess the two methods .Results:The duration of extraction of drill group was shorter than chisel extraction group , which had statisti-cal differences between the two groups (P<0.05).The drill group had less postoperative complication such as ache , swelling, limited opening of mouth than those of the chisel extraction group (P<0.05).Occurrence of the inferior alveolar nerve injury , mandibular fracture , adjacent tooth damage and dry sock were lower than chisel extraction group (P<0.05).Conclusions:High-speed air tutbine drill with its evident superiority to traditional chisel , when applied in the extraction of low impacted teeth , can efficiently cut down duration of extraction , reduce the incidence of the intraoperative and postoperative complication and is therefore recommendable in clinical practice .%目的:对比高速涡轮气钻法与凿骨劈冠法拔除下颌水平埋伏阻生智齿的临床疗效。方法:回顾分析口腔门诊120颗低位水平阻生智齿患者的临床资料,其中采用传统的凿骨劈冠法拔除60颗为锤凿组,采用高速涡轮气钻拔除60颗为涡轮钻组,对2组手术时间及术中、术后并发症发生情况进行观察和对比分析。结果:涡轮钻组拔牙时间短于锤凿组,差异有统计学意义( P<0.05)。涡轮钻组术中邻牙损伤、下齿槽神经损伤和下颌角骨折的发生率以及术后颊面部的肿胀、疼痛程度、张口

  15. Rendimento da soja e intervalo hídrico ótimo em latossolo vermelho sob plantio direto escarificado Soybean grain yield and least limiting water range in an oxisol under chiseled no-tillage

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    Vilson Antonio Klein

    2007-04-01

    Full Text Available O intervalo hídrico ótimo (IHO é um método que integra vários fatores que afetam o desenvolvimento das plantas, e corresponde ao intervalo de umidade do solo no qual não ocorre restrição de aeração (porosidade de aeração mínima de 0,10 m³ m-3 nem de resistência mecânica à penetração das raízes (RP dentro da faixa de água disponível às plantas, isto é, entre a capacidade de campo (CC e o ponto de murcha permanente (PMP. O objetivo deste trabalho foi determinar o IHO em um Latossolo Vermelho sob plantio direto (PD e plantio direto escarificado (PDE, bem como o rendimento de grãos de soja. Avaliou-se a densidade do solo, o IHO, a variação da umidade do solo durante o ciclo da soja e o rendimento de grãos. Os resultados indicaram que a densidade do solo foi menor no PDE, o que acarretou maior amplitude do IHO. A densidade crítica, na qual IHO = 0, foi semelhante entre o PD e o PDE. Durante o ciclo da cultura da soja, em vários momentos, a sua umidade ficou fora do IHO, quando assumida RP limitante de 2 MPa. Como o rendimento de grãos da soja não apresentou diferença significativa, deduz-se que a RP de 2 MPa não é limitante para a soja.The least limiting water range (LLWR was used to determine several factors that influence plant growth. The LLWR is defined as the water content range in which aeration (AFP and soil resistance to root penetration (RP are not restrictive, within the field capacity (FC and permanent wilting point (PWP. The aim of the present study was to determine the LLWR and soybean grain yield in an Oxisol under non-tillage (NT and chiseled no-tillage (CNT systems. The soil density, LLWR, soil water content range throughout the soybean crop cycle and grain yield were assessed. Soil density was lower in the CNT system, which resulted in a wider LLWR. Critical density (LLWR=0 was similar in the NT and CNT systems. The soil water content decreased to values outside the LLWR at different periods during

  16. Efeitos da escarificação na qualidade física de um latossolo vermelho distroférrico após treze anos de semeadura direta Effects of chiseling on physical quality of a dystroferric red latosol after thirteen years of no-tillage

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    M. A. Araujo

    2004-06-01

    Full Text Available O objetivo deste trabalho foi avaliar as alterações na qualidade física de um Latossolo Vermelho distroférrico provocadas pela escarificação, após 13 anos de semeadura direta. O experimento constituiu-se de dois tratamentos: escarificação do solo a 0,30 m de profundidade (SDE e testemunha mantendo a semeadura direta (SD. Amostras de solo, com estrutura não deformada, foram coletadas nas profundidades de 0-0,15 m e 0,15-0,30 m, a partir das quais foram determinados a curva de retenção de água, a curva de resistência do solo à penetração, a densidade do solo e o "Intervalo Ótimo de Tensão da Água no Solo" (IOP. Os resultados mostraram que, na profundidade de 0-0,15 m, a escarificação promoveu modificações na porosidade do solo, mantendo condições adequadas de aeração em tensões matriciais menores do que 0,01 MPa. Por outro lado, no solo escarificado, constatou-se a maior ocorrência de limitações pela resistência do solo à penetração em tensões menores do que 1,5 MPa. Para a camada de 0,15-0,30 m, no tratamento SDE, a resistência do solo à penetração foi o limite superior do IOP. Os resultados deste estudo sugerem que, neste solo e sob esta condição de manejo, não é necessária a escarificação.The objective of this study was to evaluate alterations in the physical soil quality of a Dystroferric Red Latosol (Typic Haplorthox caused by chiseling, after thirteen years of no-tillage. The experiment consisted of two management systems: soil chiseling down to a 0.30 m depth (NTC and no-tillage (NT. Undisturbed soil samples were collected at depths of 0-0.15 m and 0.15-0.30 m, and the soil water retention curve, the soil resistance to penetration curve, the soil bulk density, and the "Least Limiting Water Potential" (LLWP were determined. The results showed that the chiseling caused modifications in soil porosity in the 0-0.15 m layer, maintaining appropriate aeration conditions in water matric potentials

  17. Eficiência da escarificação mecânica e biológica na melhoria dos atributos físicos de um latossolo muito argiloso e no incremento do rendimento de soja Efficiency of mechanical and biological chiseling in the improvement of physical attributes of a heavy clay oxisol and the increment of soybean yield

    Directory of Open Access Journals (Sweden)

    Rodrigo da Silveira Nicoloso

    2008-08-01

    tratamento ESC-Av teve comportamento intermediário. Os tratamentos SD-Nb+Av e ESC-Nb+Av aumentaram, em média, 46,6 % a lâmina de água infiltrada em relação aos tratamentos SD-Av e ESC-Av. O maior rendimento de grãos de soja foi observado no tratamento ESC-Nb+Av (3,73 Mg ha-1, que não diferiu significativamente do SD-Nb+Av (3,49 Mg ha-1. A escarificação mecânica do solo teve efeito temporário, e não foram constatadas melhores condições físicas do solo após nove meses, com exceção do aumento da porosidade total e macroporosidade do solo na camada 0-0,05 m. Por outro lado, a escarificação biológica aumentou a macroporosidade do solo, diminuiu sua resistência à penetração e melhorou a infiltração de água. A escarificação mecânica foi uma alternativa eficiente em melhorar as condições físicas do Latossolo textura muito argilosa quando associada à escarificação biológica, que preveniu a reconsolidação do solo.Compaction is one of the main causes of yield decreases in agricultural soils. Mechanical chiseling has been suggested to reduce soil compaction in long-term no-tillage systems. Another option to alleviate soil compaction is the use of cover crops, such as forage radish, with a well-developed tap root system and the capacity of growing into soil compacted layers, forming stable biopores and improving the soil physical properties. This study aimed to evaluate the efficiency of a mechanical (chisel plow and biological (forage radish soil decompaction method or the combination of both to improve the physical properties of a very clayey texture Oxisol and to increase soybean grain yield under no-tillage. The treatments were: black oat on no-till (NT-O, consortium of forage radish and black oat on no-till (NT-R+O, black oat on chiseled soil (CH-O and consortium of forage radish and black oat on chiseled soil (CH-R+O. The following properties were evaluated: soil bulk density, macroporosity, microporosity and total porosity in the layers 0

  18. Escarificação mecânica e biológica para a redução da compactação em argissolo franco-arenoso sob plantio direto Mechanical and biological chiseling to reduce compaction of a sandy loam alfisol under no-tillage

    Directory of Open Access Journals (Sweden)

    S. L. Abreu

    2004-06-01

    saturado, em médio prazo, a "escarificação biológica" (CM-crot mostrou-se mais eficaz na ruptura da camada compactada e estabelecimento de poros condutores de água do que a escarificação mecânica (Esc-soja do solo. Em contrapartida, se o indicador for a RP, o resultado é inverso. Assim, a propriedade hídrica ou mecânica do solo a ser usada como indicadora para a avaliação da eficácia da ruptura da camada compactada do solo depende do processo físico priorizado: a infiltração e redistribuição de água ou a penetração e crescimento de raízes.Soil management alters the physical soil properties and changes the soil air, water, and solute dynamics. Physical soil properties as affected by conservationist soil management systems were studied in a sandy loam Typic Hapludalf. The treatments were established on a soil that has been under no-tillage for 10 years, and consisted of: no-tillage soybeans, chisel tillage soybeans, reduced tillage Crotalaria, and bare soil without tillage. The evaluated soil properties were soil penetration resistance, bulk density, porosity, pore size distribution, saturated and unsaturated hydraulic conductivity, water infiltration using concentric rings or natural rainfall, variation of the volumetric soil moisture throughout the cropping cycle, and water retention curve. Soil penetration resistance (PR was highest at 0.075 m and 0.175 m depth in no-tillage and chiseled soil, respectively. Soil subsurface mobilization with chiseling and surface mobilization due to disking and sowing did not influence the bulk density (BD after the crop harvest. No-till soil under soybean crop had greater macroporosity than reduced tillage crotalaria and bare soil at 0.02 to 0.05 m depth, resulting in a greater saturated hydraulic conductivity and lower water retention during periods of low water availability. Among the analyzed soil physical-mechanical properties, PR seemed to be more sensitive to detect soil compaction than BD or porosities

  19. Алгоритм діагностики і вибору методу лікуваня пацієнтів з адентією верхніх латеральних різців = Algorithm of clinical inspection and choosing a method of treatment of patients from by the aedentia of overhead lateral chisels

    OpenAIRE

    Yakymets, A V; Drogomyrec'ka, M S

    2015-01-01

    Yakymets A V, Drogomyrec'ka M S. Алгоритм діагностики і вибору методу лікуваня пацієнтів з адентією верхніх латеральних різців = Algorithm of clinical inspection and choosing a method of treatment of patients from by the aedentia of overhead lateral chisels. Journal of Education, Health and Sport. 2015;5(5):233-242. ISSN 2391-8306. DOI 10.5281/zenodo.17596 http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%285%29%3A233-242 https://pbn.nauka.gov.pl/works/559890 http://d...

  20. A New Model of Teaching Pedagogy in CHISEL for the 21th Century.

    Science.gov (United States)

    Huang, Li-yi

    This paper describes and compares six models for teaching second languages developed and adopted since 1840 (grammar-translation, direct, structural, situational, audiolingual, and communicative methods), and proposes a seventh, the cognitive-linguistic method, incorporating Noam Chomsky's theory of learning. The model takes both extralinguistic…

  1. The influence of vibration and noise from a handheld pneumatic (sculptors) chisel on the human cardiovascular system

    OpenAIRE

    Franken, Anja; Eloff, Frederik; Du Plessis, Johannes; Van Aarde, Michiel; Laubscher, Petrus

    2009-01-01

    Noise-induced hearing loss (NIHL) in the South African mining industry can be prevented, but only by incorporating more proactive and innovative measures into NIHL prevention programmes. At present, direct and indirect costs to the mining industry resulting from occupational noise are unacceptable and, more importantly, mineworkers' quality of life is being eroded. Researchers at the Council for Scientific and Industrial Research Laboratory for Mining Innovation (LMI) propose that the large d...

  2. Influence of chisel width on shear bond strength of composite to enamel = Influência da largura do cinzel sobre a resistência ao cisalhamento da união esmalte/resina composta

    OpenAIRE

    Oliveira, Antônio Carlos Castellan de

    2009-01-01

    Objetivo: Avaliar a influência de diferentes larguras de cinzel sobre a resistência de união ao cisalhamento na interface esmalte dental/resina composta. Metodologia: As coroas de 60 dentes incisivos bovinos foram incluídas em resina acrílica e as superfícies vestibulares de esmalte foram planificadas e condicionadas com ácido fosfórico a 35 %. O sistema adesivo Single Bond (3M/ESPE) e de resina composta Z-250 (3M/ESPE) foram utilizados para fabricar restaurações cilíndricas de resina compost...

  3. Rendimento da soja e intervalo hídrico ótimo em latossolo vermelho sob plantio direto escarificado Soybean grain yield and least limiting water range in an oxisol under chiseled no-tillage

    OpenAIRE

    Vilson Antonio Klein; Rodrigo Kurylo Camara

    2007-01-01

    O intervalo hídrico ótimo (IHO) é um método que integra vários fatores que afetam o desenvolvimento das plantas, e corresponde ao intervalo de umidade do solo no qual não ocorre restrição de aeração (porosidade de aeração mínima de 0,10 m³ m-3) nem de resistência mecânica à penetração das raízes (RP) dentro da faixa de água disponível às plantas, isto é, entre a capacidade de campo (CC) e o ponto de murcha permanente (PMP). O objetivo deste trabalho foi determinar o IHO em um Latossolo Vermel...

  4. Validação de teorias de simulação para operações com escarificadores em solo argiloso no planalto do Estado do Rio Grande do Sul, Brasil Validation of prediction theories to chisel plow in soils of Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Paula Machado dos Santos

    2011-01-01

    Full Text Available O objetivo deste trabalho foi estudar teorias, utilizadas especialmente para simular situações reais de campo, contrastada por dados empíricos obtidos em condições reais de trabalho agrícola mecanizado em solo de textura argilosa com os resultados obtidos em trabalhos semelhantes realizados em outros países. Avaliou-se as demandas de tração de diferentes combinações entre velocidade e profundidade de trabalho de um escarificador. Buscou-se a representação gráfica da demanda requerida de força de tração e patinagem através da utilização do software Predição versão 1.0, contrastadas com resultados obtidos pela aplicação das teorias de predição Cn, Bn e Mn. As teorias preditivas Cn, Bn e Mn apresentam correlação boa com os valores experimentais, no entanto, existe uma superestimativa por parte das teorias comparadas aos valores medidos experimentalmente, para força de tração e patinagem, causando um dimensionamento do trator inadequado.The objective of this research was studied theories used specially to simulate real field situations contrasted by empiric data obtained in real real working conditions in mechanized agricultural clay soil with the results obtained in similar studies conducted in other countries. We tried to the graphical representation of the demand required traction force and slippage through the use of Prediction software version 1.0, contrasted with results obtained by applying the theories of prediction Cn, Bn and Mn. Predictive theories Cn, Bn and Mn have good correlation with experimental values, however, there is an overestimation by the theory compared to the values measured experimentally, for traction force and slippage, causing a tractor design inadequate.

  5. Modified ridge splitting and bone expansion osteotomy for placement of dental implant in esthetic zone

    Directory of Open Access Journals (Sweden)

    Mayur S Khairnar

    2014-01-01

    Full Text Available Ridge splitting with bone expansion is a technique of manipulation of bone to form receptor site for implant without removing any bone from the implant site. Maxillary bone has inherent quality of flexibility which can bemolded to desire location by using series of instrument namely chisels and osteotome. This further improves quality of bone all around implant, at the crest and apex both. This article describes a report of a clinical case with management of bucco-palatal ridge defect with modified ridge splitting and expansion osteotomy technique using chisel and osteotomes in an esthetic zone.

  6. Modified ridge splitting and bone expansion osteotomy for placement of dental implant in esthetic zone.

    Science.gov (United States)

    Khairnar, Mayur S; Khairnar, Darshana; Bakshi, Kedar

    2014-01-01

    Ridge splitting with bone expansion is a technique of manipulation of bone to form receptor site for implant without removing any bone from the implant site. Maxillary bone has inherent quality of flexibility which can bemolded to desire location by using series of instrument namely chisels and osteotome. This further improves quality of bone all around implant, at the crest and apex both. This article describes a report of a clinical case with management of bucco-palatal ridge defect with modified ridge splitting and expansion osteotomy technique using chisel and osteotomes in an esthetic zone. PMID:24808709

  7. ACCUMULATION AND CROP UPTAKE OF SOIL MINERAL NITROGEN AS INFLUEMCED BY TILLAGE, COVER CROPS, AND NITROGEN FERTILIZATION

    Science.gov (United States)

    Soil and crop management practices may influence soil mineral N, crop N uptake, and N leaching. We evaluated the effects of three tillage practices [no-till (NT), strip till (ST), and chisel till (CT)], four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secaele cereale L.)]...

  8. Soil and crop nitrogen as influenced by tillage, cover crops, and nitrogen fertilization

    Science.gov (United States)

    Soil and crop management practices may influence soil mineral N, crop N uptake, and N leaching. We evaluated the effects of three tillage practices [no-till (NT), strip till (ST), and chisel till (CT)], four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)],...

  9. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... technically there’s sometimes a bit more of a challenge to it because you’re putting something that’s ... Well it’s not something you learn in med school. This is on operation kind that takes ... First, the primary chisel is inserted over the trial and advanced ...

  10. Global Warming Potential of Organic and Conventional Grain Cropping Systems in the mid-Atlantic Region of the U.S.

    Science.gov (United States)

    The global warming potential (GWP) of a cropping system is the balance between the net exchange of the greenhouse gases CO2, N2O and CH4 that result from on-farm practices and the production and transport of inputs. We report here on GWP calculations for no-till (NT), chisel till (CT) and organic (O...

  11. Annual Research Review: Parenting and Children's Brain Development--The End of the Beginning

    Science.gov (United States)

    Belsky, Jay; de Haan, Michelle

    2011-01-01

    After questioning the practical significance of evidence that parenting influences brain development--while highlighting the scientific importance of such work for understanding "how" family experience shapes human development--this paper reviews evidence suggesting that brain structure and function are "chiselled" by parenting. Although the…

  12. Basic Hand Tools for Bricklaying and Cement Masonry [and] Basic Hand Tools of the Carpenter.

    Science.gov (United States)

    Texas A and M Univ., College Station. Vocational Instructional Services.

    Intended for student use, this unit discusses and illustrates the tools used in brick and masonry and carpentry. Contents of the brick and masonry section include informative materials on bricklaying tools (brick trowels, joint tools, levels, squares, line and accessories, rules, hammers and chisels, tool kits) and cement masonry tools (tampers,…

  13. Material characterization of ancient Indian copper

    Indian Academy of Sciences (India)

    A Srivastava; R Balasubramaniam

    2003-10-01

    A chalcolithic (2350–1800 BC) copper chisel from Balathal has been characterized by X-ray diffraction, microstructural and electrochemical methods. The surface patina was composed of sulfates and oxysulfates in the outer layers while the inner layers were rich in copper oxides. The chisel exhibited smaller grain sizes near two of the surfaces while the structure in the interior was equiaxed. The deformed grains and inclusions near the surfaces and variation in the microhardness of the sample from different faces proved that the copper chisel was processed by cold deformation after initial casting of the square cross-section chisel. The electrochemical behaviour of chalcolithic Cu has been compared with that of a modern Cu sample by potentiodynamic polarization studies. The corrosion rate of chalcolithic Cu in aerated 3.5% NaCl solution was only marginally higher than that of modern Cu. The higher rate of corrosion has been attributed to the presence of second phase sulfide inclusions. The excellent condition of preservation of the 3800-year-old copper object, with no indications of stress corrosion cracking, suggests that pure copper or copper-based materials can be seriously considered as candidate canister materials for long-term underground storage of nuclear wastes in underground repositories.

  14. The Cheops mystery targeted with neutrons

    NARCIS (Netherlands)

    Van de Graaf, A.

    2005-01-01

    How the ancient Egyptians managed to raise a seven million tonne pyramid in a time span of only twenty years remains a mystery. Every now and then discussions flare up as to how exactly the pyramids at Giza in Egypt were constructed. How could they cut stone without the necessary chisels? How did th

  15. MAIZE YIELD AND ITS STABILITY AS AFFECTED BY TILLAGE AND CROP RESIDUE MANAGEMENT IN THE EASTERN ROMANIAN DANUBE PLAIN

    Directory of Open Access Journals (Sweden)

    Alexandru COCIU

    2015-10-01

    Full Text Available Rainfed crop management systems need to be optimized to provide more resilient options in order to cope with projected climatic scenarios which are forecasting a decrease in mean precipitation and more frequent extreme drought periods in the Eastern Romanian Danube Plain. This research, carried out in the period of 2011-2014, had as main purpose the determination of influence of tillage practices and residue management on rainfall use efficiency, maize yield and its stability, in order to evaluate the advantages of conservation agriculture (CA in the time of stabilization of direct seeding effects, in comparison with traditional chisel tillage. The maize grain yields are presented for each crop management practices, as follows: (1 chisel tillage, retained crop residues being chopped and incorporated (ciz; (2 zero tillage, retained crop residue chopped and kept on the field in short flat condition (rvt; (3 zero tillage, crop residues kept on the field in short root-anchored condition (1/2rva, and (4 zero tillage, crop residues kept on the field in tall root-anchored condition (1/1rva. In 2012, a year with prolonged drought during vegetative growth, yield differences between zero tillage with short root-anchored residue retention (1/2rva and chisel tillage with residue incorporation (ciz were positive, up to 840 kg ha-1. In average over 2011-2014, conservation agriculture (CA practices had a yield advantage over traditional chisel tillage practice. Zero tillage with residue retention used rainfall more efficiently so suggesting that it is a more resilient agronomic system than traditional (conventional practices involving chisel tillage with residue incorporation.

  16. The earliest herbivorous marine reptile and its remarkable jaw apparatus.

    Science.gov (United States)

    Chun, Li; Rieppel, Olivier; Long, Cheng; Fraser, Nicholas C

    2016-05-01

    Newly discovered fossils of the Middle Triassic reptile Atopodentatus unicus call for a radical reassessment of its feeding behavior. The skull displays a pronounced hammerhead shape that was hitherto unknown. The long, straight anterior edges of both upper and lower jaws were lined with batteries of chisel-shaped teeth, whereas the remaining parts of the jaw rami supported densely packed needle-shaped teeth forming a mesh. The evidence indicates a novel feeding mechanism wherein the chisel-shaped teeth were used to scrape algae off the substrate, and the plant matter that was loosened was filtered from the water column through the more posteriorly positioned tooth mesh. This is the oldest record of herbivory within marine reptiles. PMID:27386529

  17. The Location of the Maximum Temperature on the Cutting Edges of a Drill

    Energy Technology Data Exchange (ETDEWEB)

    Bono, M J; Ni, J

    2005-01-07

    This study analyzes the temperature profile along the cutting edges of a drill and describes how the temperature on the chisel edge can exceed the temperature on the primary cutting edges. A finite element model predicts the temperature distribution in the drill, where the heat flux loads applied to the finite element model are determined from analytical equations. The model for the heat flux loads considers both the heat generated on the shear plane and the heat generated on the rake face of the tool to determine the amount of heat flowing into the tool on each segment of the cutting edges. Contrary to the conventional belief that the maximum temperature occurs near the outer corner of the drill, the model predicts that the maximum temperature occurs on the chisel edge, which is consistent with experimental measurements of the temperature profile.

  18. Assessing the Soil Physiological Potential Using Pedo-Biological Diagnosis Under Minimum-Tillage System and Mineral Fertilization

    Directory of Open Access Journals (Sweden)

    Lazar Bireescu

    2014-11-01

    Full Text Available The main objective of sustainable agriculture is the protection of environment and natural vegetal and soil resources. Accordingly, the objective of this research was to assess the impact of technological systems by minimum tillage on soil biological activity, using the Pedo-Biological Diagnosis of Soil Resources. Our research was conducted on haplic chernozem from Experimental Station of UASVM of Iasi, Romania, during the seasonal dynamic, to the soybean crop, on unfertilized and fertilized agrofond, using moderate mineral doses (N80P80 as average of 2009–2010 period, under minimum tillage (2x disk, paraplow, chisel compared to conventional (plugging at 20 cm and 30 cm. In the case of soil works with chisel and paraplow without return of furrow, the Pedo-Biological Diagnosis highlights an increase of soil physiological potential, in the both variants (unfertilized and fertilized, unlike the method of alternating the depth of plugging that proved to be ineffective.

  19. Impressive: printmaking, letterpress and graphic design

    OpenAIRE

    Wood, Philippa

    2010-01-01

    Inspired by the challenge of hands-on tweaks and unpredictable results as well as the tactile qualities of different inks, papers, and binding techniques, today’s creatives are rediscovering old-fashioned printing methods and crafts. Impressive is a topical exploration of the interplay between current trends in graphic design and traditional handiwork such as letterpress printing, hand-cut linotype, chiselled woodblocks, and embossing. In addition to a rich selection of invitations, business ...

  20. Sugar cane management with humic extract and organic and mineral fertilizer: impacts on Oxisol some physical properties

    Science.gov (United States)

    Alves, M. C.; Campos, F. S.; Souza, Z. M.

    2012-04-01

    The present investigation has as objective to study the impact of cultive systems, humic extract and organic and mineral fertilizers on Oxisol some physical properties cultivated of sugar cane. It was developed in Aparecida do Taboado, Mato Grosso do Sul, Brazil, in Manufactores Alcoolvale. The study was in sugar cane culture implanted on 3th and 4th cycle. The experimental design was at randomized blocks following scheme in zone with eight treatments and four replications. The two treatments in main zone were represented by cultivation systems (with and without chisel) and the subzone fertilization (T1-mineral, T2-mineral+sugar cane residue, T3-mineral+humic and fulvic acids and T4-mix of mineral, sugar cane residue and humic and fulvic acids). In three soil layers: 0.00-0.05; 0.10-0.20 and 0.20-0.40 m were studied the physical soil properties: macroporosity, microporosity, total porosity and soil bulk density. Also evaluate the technological quality of sugar cane. The conclusions are: the application of mineral fertilizer+sugar cane residue+humic extract (Humitec ®) and cropping system with chisel were more effective in improving soil physical; the system of crop of sugar cane ratton implanted in the 2th and 3th cycle, without the use of chisel was better in the recovery of soil physical properties; the crop system without the chisel and the combination of mineral fertilizer+sugar cane residue was promising to increase of Brix, Pol juice, Pol sugar cane and total recoverable sugars Pol.

  1. 木材加工教育用ビデオ教材の制作(2) : 手彫りによる中仕工かんな台の製作

    OpenAIRE

    番匠谷, 薫; 池田, 豊; 矢田部, 敏夫; 藤元, 嘉安; 真鍋, 正男

    1993-01-01

    Formerly in Japan, carpenter's making of plane stock made of shirakashi (Quercus myrsinaefolia Blume) of Japanese hand plane was done by hand making with chisel. This traditional concept of hand making of wooden plane stock can be regarded to be very important for teachers of industrial arts of junior high schools in Japan because its making skill can lead them to deep understandings of the Japanese hand plane. It also provides a totally skilled back ground concerning the Japanese hand plane ...

  2. Shear Strengthening of RC Beams Using Sprayed Glass Fiber Reinforced Polymer

    OpenAIRE

    Sayed Mohamad Soleimani; Nemkumar Banthia

    2012-01-01

    The effectiveness of externally bonded sprayed glass fiber reinforced polymer (Sprayed GFRP) in shear strengthening of RC beams under quasi-static loading is investigated. Different techniques were utilized to enhance the bond between concrete and Sprayed GFRP, involving the use of through bolts and nuts paired with concrete surface preparation through sandblasting and through the use of a pneumatic chisel prior to Sprayed GFRP application. It was found that roughening the concrete surface us...

  3. Long-Term Effects of Cover Crops on Crop Yields, Soil Organic Carbon Stocks and Sequestration

    OpenAIRE

    Kenneth Olson; Stephen A. Ebelhar; Lang, James M.

    2014-01-01

    A 12-year cover crops study on the effects on SOC sequestration, storage, retention and loss and corn and soybean yields was conducted in southern Illinois. The use of cover crops for the maintenance and restoration of soil organic carbon (SOC) and soil productivity of previously eroded soils were evaluated. No-till (NT), chisel plow (CP), and moldboard plow (MP) treatment plots with and without cover crops were established in 2001. The plot area was on sloping with a ...

  4. Hodnocení kvality zpracování půdy u vybraných strojů pro hlubší kypření bez obracení půdy

    OpenAIRE

    Knap, Petr

    2013-01-01

    The aim of this thesis is to evaluate the quality of soil tillage with machines for deep tillage without turning over the soil. Quality of machine work is assessed after crossing machine through a field. The evaluated parameters of the work quality are: surface cover of crop residue, bottom profiles soil tillage, surface profile and processed soil surface roughness. There are compared three-row chisel cultivators, Strom Export Ecoland, Lemken Karat 9 and Horsch Terrano FX.

  5. Effect of soil moisture deficit in the upper root zone on growth and yield of soybeans

    Energy Technology Data Exchange (ETDEWEB)

    Anwar-ul-Haq; Brown, D.A.

    Soybean producers in Arkansas frequently are confronted with drought conditions which limit yields. These moisture deficit periods result in decreased water and nutrient absorption which adversely affects root growth and distribution within the soil profile, bloom set, and seed-pod retention. Producers have attempted to eliminate this problem by irrigation, by the use of drought tolerant cultivars, and by chiseling to provide for greater root penetration into the subsoil.

  6. Detection of Microcracks During Bone Cutting Using Acoustic Emission Techniques

    OpenAIRE

    Safari, Ashkan; Reilly, Ger; McCormack, Brendan

    2005-01-01

    Surgeons may use a number of cutting instruments such as osteotomes and chisels to cut bone during operative procedures. The initial loading of cortical bone during the cutting process results in the formation of microcracks in the vicinity of the cutting zone with main crack propagation to failure occurring with continued loading; microcracking acts as a stimulus for main crack formation and has also been shown to occur during the propagation of the main crack. It has also been reported that...

  7. Critical limits of soil penetration resistance in a rhodic Eutrudox

    Directory of Open Access Journals (Sweden)

    Moacir Tuzzin de Moraes

    2014-02-01

    Full Text Available Soil penetration resistance is an important indicator of soil physical quality and the critical limit of 2 MPa has been widely used to characterize the soil physical quality, in both no-tillage and conventional systems. The aim of this study was to quantify the influence of different tillage and cropping systems on the soil penetration resistance in a Rhodic Eutrudox. The experiment was carried out in a 5 × 2 factorial, completely randomized block design (tillage systems vs cropping systems, with four replications. The tillage systems consisted of: conventional tillage disk harrow; minimum tillage with annual chiseling; minimum tillage with chiseling every three years; no-tillage for 11 consecutive years; and no-tillage for 24 consecutive years. The factor cropping systems was represented by: crop rotation and crop succession. The soil penetration resistance (SPR was determined in 20 soil samples per treatment and layer (0.0-0.10; 0.10-0.20 and 0.20-0.30 m for each soil matric potential: -6, -10, -33, -100, -500 kPa. The SPR was determined at a volumetric soil water content equivalent to the fraction of plant-available water of 0.7. There were no differences of soil penetration resistance between the two cropping systems. Differences in soil penetration resistance among tillage systems were related to the matric potential at which the samples were equilibrated. The critical SPR limit of 2 MPa normally used for conventional tillage should be maintained. However, this value of 2 MPa is inappropriate for the physical quality characterization of Rhodic Eutrudox under no-tillage and/or minimum tillage with chiseling. Regardless of the cropping systems, the critical SPR limit should be raised to 3 MPa for minimum tillage with chiseling and to 3.5 MPa for no-tillage.

  8. Effect of integrated reservoir tillage for in-situ rainwater harvesting and other tillage practices on soil physical properties

    OpenAIRE

    Salem, Haytham M.; Valero Ubierna, Constantino; Muñoz García, Miguel Angel; Gil Rodríguez, María

    2015-01-01

    There is a need for in-situ soil moisture conservation in arid and semi-arid regions due to insufficient rainfall for agriculture. For this purpose, a combination implement [integrated reservoir tillage system (RT)] comprised of a single-row chisel plow, single-row spike tooth harrow, modified seeder, and spiked roller was developed and compared to the popular tillage practices, viz., minimum tillage (MT) and conventional tillage (CT) in an arid Mediterranean environment in Egypt. The differe...

  9. The Impact of Various Types of Tillage on the Soil Water Availability

    OpenAIRE

    BESNIK GJONGECAJ; PIRRO VEIZI

    2014-01-01

    The present study is focused on the role that various ways of soil tillage may have on the increase of soil water availability to the plant roots. The research was carried out in Tirana, Albania, and the experiment was established in a vineyard field. The soil was cultivated in three different ways (three treatments): conventional (plowing plus surface cultivation), conservative (subsoiling plus surface cultivation), conservative (chisel plowing plus surface cultivation). In order to quantify...

  10. Influence of different soil preparation techniques on organically grown strawberries

    OpenAIRE

    Leona, Brockamp; Eis, Birgit

    2008-01-01

    From June 2005 till June 2007 different soil preparation techniques like chiselling and advance sowing of medicinal plants and green manuring were proofed for their influence on reducing plant losses of strawberries caused by root diseases like Phytophthora species and Verticillium dahliae. The variants were combined with potted plants and Frigos. The experiment took place on an organic fruit farm near Stuttgart, Germany, with the strawberry variety ´Elsanta´. Focused on root diseases, hab...

  11. Root-Knot Nematode Management in Double-Cropped Plasticulture Vegetables

    OpenAIRE

    Desaeger, J. A.; Csinos, A. S.

    2006-01-01

    Combination treatments of chisel-injected fumigants (methyl bromide, 1,3-D, metam sodium, and chloropicrin) on a first crop, followed by drip-applied fumigants (metam sodium and 1,3-D ± chloropicrin) on a second crop, with and without oxamyl drip applications were evaluated for control of Meloidogyne incognita in three different tests (2002 to 2004) in Tifton, GA. First crops were eggplant or tomato, and second crops were cantaloupe, squash, or jalapeno pepper. Double-cropped vegetables suffe...

  12. Modified ridge splitting and bone expansion osteotomy for placement of dental implant in esthetic zone

    OpenAIRE

    Mayur S Khairnar; Darshana Khairnar; Kedar Bakshi

    2014-01-01

    Ridge splitting with bone expansion is a technique of manipulation of bone to form receptor site for implant without removing any bone from the implant site. Maxillary bone has inherent quality of flexibility which can bemolded to desire location by using series of instrument namely chisels and osteotome. This further improves quality of bone all around implant, at the crest and apex both. This article describes a report of a clinical case with management of bucco-palatal ridge defect with mo...

  13. Paint Scaler. Innovative Technology Summary Report

    International Nuclear Information System (INIS)

    The Paint Scaler can collect paint samples quickly and efficiently for lab analysis. The Rotary Hammer Drill is a 24-V battery operated, 3/4-in. rotary hammer drill. When used with an optional chipping adapter, the Bosch Rotary Hammer Drill can be used to perform chipping and chiseling tasks such as paint removal from either concrete or metal surfaces. It is ultra-compact, lightweight with an ergonomic balanced grip. The battery operation gives the operator more flexibility during sampling activities

  14. Effect of cultural practices and fertilizers on sunflower yields in long term experiments

    OpenAIRE

    Petcu Gh; Petcu E.

    2006-01-01

    Field experiments were conducted during 1980-2004 at Agricultural Research and Development Institute from Fundulea (Romania) on a leached chernozem soil, well drained, formed on loess, with 33% clay content and 2.8% organic matter in the arable layer. The paper presents aspects regarding the influence of different soil tillage methods (moldboard plow, chisel paraplow, disking), fertilizers and track by track successive passings of tractor (from 1 to 3) prior to seedbed preparation on sunflowe...

  15. Optical coherence tomography to evaluate the interaction of different edge designs of four different silicone hydrogel lenses with the ocular surface

    OpenAIRE

    Turhan, Semra

    2015-01-01

    Semra Akkaya Turhan, Ebru Toker Department of Ophthalmology, School of Medicine, University of Marmara, Istanbul, Turkey Purpose: To evaluate the lens edge interaction with the ocular surface with different edge designs using optical coherence tomography and to examine the effect of lens power on the lens edge interactions. Methods: Four types of silicone hydrogel lenses with different edge designs (round-, semi-round-, chisel-, and knife-edged) at six different powers (+5.0, +3.0,...

  16. Optical coherence tomography to evaluate the interaction of different edge designs of four different silicone hydrogel lenses with the ocular surface

    OpenAIRE

    Turhan SA; Toker E

    2015-01-01

    Semra Akkaya Turhan, Ebru Toker Department of Ophthalmology, School of Medicine, University of Marmara, Istanbul, Turkey Purpose: To evaluate the lens edge interaction with the ocular surface with different edge designs using optical coherence tomography and to examine the effect of lens power on the lens edge interactions. Methods: Four types of silicone hydrogel lenses with different edge designs (round-, semi-round-, chisel-, and knife-edged) at six different powers (+5.0, +3.0, +1....

  17. An Effective Method for Improvement of Field Electron Emission Site Density and Uniformity of Amorphous Carbon Thin Films

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Ping; WANG Li-Jun; ZHANG Bing-Lin; YAO Ning; ZANG Qi-Ren; CHEN Jun; DUAN Xin-Chao

    2006-01-01

    @@ Amorphous carbon films are deposited on the Mo film/ceramic substrates, which are pretreated by a laser spat-tering chiselling technique (2 line/mm), by using the microwave chemical vapour deposition technique. The films are characterized by x-ray diffraction, Raman spectrum, optical microscopy, and scanning electron microscopy.The experimental result indicates that the laser spattering chiselling pretreated techniques can essentially improve the field emission uniformity and the emission site density of the amorphous carbon thin film devices so that its emission site density can reach the level of actual application (undistinguishable by naked eye) from a broad well-proportioned emission area of 50mm × 50mm. This kind of device can show various digits and words clearly. The lowest turn-on field below 1 V/m, the emission current density over 5.0 ±0.1 mA/cm2, and the highest luminance 1.0 × 103 cd/m2 are obtained. Meanwhile, the role of the laser spattering chiselling techniques in improving the field emission properties of the amorphous carbon film are explained.

  18. Optimization of process parameters in drilling of GFRP composite using Taguchi method

    Directory of Open Access Journals (Sweden)

    Vinod Kumar Vankanti

    2014-01-01

    Full Text Available The objective of the present work is to optimize process parameters namely, cutting speed, feed, point angle and chisel edge width in drilling of glass fiber reinforced polymer (GFRP composites. In this work, experiments were carried out as per the Taguchi experimental design and an L9 orthogonal array was used to study the influence of various combinations of process parameters on hole quality. Analysis of variance (ANOVA test was conducted to determine the significance of each process parameter on drilling. The results indicate that feed rate is the most significant factor influencing the thrust force followed by speed, chisel edge width and point angle; cutting speed is the most significant factor affecting the torque, speed and the circularity of the hole followed by feed, chisel edge width and point angle. This work is useful in selecting optimum values of various process parameters that would not only minimize the thrust force and torque but also reduce the delimitation and improve the quality of the drilled hole.

  19. Strip-tillage: A conservation alternative to full-width tillage systems

    Science.gov (United States)

    Wolkowski, Richard

    2015-04-01

    Historically no-till management has been a challenge for maize production in the Midwestern USA because crop residue slows the warming of the soil in the spring and can physically impair planting by plugging the planter. After trying no-till, producers often return to more aggressive tillage operations to address residue concerns; however these systems can cause soil erosion and can increase the cost of production. An alternative system known as strip-tillage has been suggested as a compromise between no-till and full-width tillage. This practice utilizes implements that loosen the soil and allow warming in the row area, yet maintain nearly as much residue as no-till. Strip-tillage is generally understood to be a single pass with a separate implement in the fall, although spring strip-tillage is possible if soil moisture and conditions permit. Strip-tillage can be accomplished in a shorter time, with lower energy and equipment inputs compared to full-width tillage. The first of two studies that examined the merits of strip-tillage was conducted the University of Wisconsin Lancaster Agricultural Research Station (42.84, -90.80). Natural runoff collectors were installed in a field having a silt loam soil with an 8% slope in fall chisel and fall strip-tillage system. The measured soil loss in a year that experienced substantial rainfall prior to canopy closure was 10.6 Mg ha-1 in chisel vs. 0.64 Mg ha-1 in strip-tillage. Soil loss was much less for both systems in the second year when early season rainfall was minimal. A second, ten year study was conducted at the University of Wisconsin Arlington Agricultural Research Station (43.30, -89.36) that compared fall strip-tillage with fall chisel/spring field cultivator and no-till systems in both a continuous maize and soybean-maize rotation. This work showed equal maize grain yield in maize after soybean when comparing chisel and strip-tillage. No-till yield was about 5 % lower. Yield in continuous maize was highest in

  20. Effects of 24 Years of Conservation Tillage Systems on Soil Organic Carbon and Soil Productivity

    OpenAIRE

    Olson, Kenneth R.; Stephen A. Ebelhar; James M. Lang

    2013-01-01

    The 24-year study was conducted in southern Illinois (USA) on land similar to that being removed from Conservation Reserve Program (CRP) to evaluate the effects of conservation tillage systems on: (1) amount and rates of soil organic carbon (SOC) storage and retention, (2) the long-term corn and soybean yields, and (3) maintenance and restoration of soil productivity of previously eroded soils. The no-till (NT) plots did store and retain 7.8 Mg C ha−1 more and chisel plow (CP) −1.6 Mg C ha−1 ...

  1. Occurrence of Euplatypus parallelus, Euplatypus sp. (col.: Euplatypodidae and Xyleborus affinis (col.: Scolytidae in Pinus sp. in Ribas do Rio Pardo, Mato Grosso do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Zanuncio José Cola

    2002-01-01

    Full Text Available Wood borer species of the families Euplatypodidae and Scolytidae were observed attacking trees of Pinus sp. in the Municipality of Ribas do Rio Pardo, state of Mato Grosso do Sul, Brazil, in March 2000. This plantation had been previously burned in an accidental fire in January 2000, causing the trees to become partially or totally unhealthy, rendering them more susceptible to attack of these pests. Galleries of these wood borers were opened with a chisel to observe parameters such as their direction and form of these galleries. Species observed as wood borers of Pinus sp. were Euplatypus parallelus, Euplatypus sp. (Coleoptera: Euplatypodidae and Xyleborus affinis (Coleoptera: Scolytidae.

  2. Distribution of Field Corn Roots and Parasitic Nematodes in Subsoiled and Nonsubsoiled Soil

    OpenAIRE

    Rich, J. R.; Hodge, C.; Robertson, W. K.

    1986-01-01

    A field trial was conducted for 2 years in an Arredondo fine sand containing a tillage pan at 15-20 cm deep to determine the influence of subsoiling on the distribution of corn roots and plant-parasitic nematodes. Soil samples were taken at various depths and row positions at 30, 60, and 90 days after planting in field corn subsoiled under the row with two chisels and in non-subsoiled corn. At 30 and 60 days, in-row nematode population densities to 60 cm deep were not affected by subsoiling c...

  3. Root growth conditions in the topsoil as affected by tillage intensity

    DEFF Research Database (Denmark)

    Kadziene, Grazina; Munkholm, Lars Juhl; Mutegi, James

    2011-01-01

    treatments were direct drilling (D), harrowing 8–10 cm (H), and ploughing (P) to 20 cm depth. A chisel coulter drill was used in the H and D treatments and a traditional seed drill in the P treatment. Undisturbed soil cores were collected in November 2008 at soil field moisture capacity from the 4–8 and 12......Many studies have reported impeded root growth in topsoil under reduced tillage or direct drilling, but few have quantified the effects on the least limiting water range for root growth. This study explored the effects of tillage intensity on critical soil physical conditions for root growth in the...

  4. Comparison of the Effects of No Tillage, Minimum Tillage and Conventional Tillage on Dry Land Wheat Yield in Pebbly Field in Tropical Region

    OpenAIRE

    N Loveimi; M. Safari; N Heidarpour

    2016-01-01

    The current study was conducted to compare different tillage methods on wheat yield in pebbly dry land areas done within three years (2006-2008) in north Khouzestan (Baghmalek city) in randomized block design with five treatments and four replications. The experimental treatments were:(1)chisel plow +seed-drill, (2)Semi plow(mold board plow with remove mold board)+seed-drill, (3)no-till-drill, (4)sweep plow +seed-drill and (5)conventional method(mold board plow+ broadcasting seed and fertiliz...

  5. Late Bronze Age Hoard studied by PIXE

    OpenAIRE

    Gutiérrez Neira, P. C.; Zucchiatti, A.; Montero-Ruiz, I.; Vilaça, R.; Bottaini, C.; Gener, M.; Climent-Font, A.

    2011-01-01

    The hoards of metallic objects belonging to the Late European Bronze Age can be interpreted differently depending on the type, number and composition of the artefacts. PIXE analysis has been performed in nine items from the Hoard of Freixanda in Portugal comprising 4 socket axes, a palstave axe, a ring, a chisel, a dagger, and a casting debris. Besides the composition of the main matrix elements, that is Cu and Sn, the amount of trace elements of interest like, As, Pb, Ni and A...

  6. CITA Working for and with material performance

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2011-01-01

    The understanding of materials as active, whether compressed, under tension or flexed while handled, is at the root of all craft traditions. The ability to work a material, to saw and chisel wood, to weld and hammer steel or to weave and knit yarn relies on a profound understanding of its...... performance. The soft flex of wood, the sprung stiffness of steel and the tensile elasticity of yarn are inherent properties that inform and shape our crafts traditions. It is through material understanding that we come to shape the world of artefacts and structure that surrounds us....

  7. Gold and Silver Inlaid Bronze Sheep

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Gold and silver inlaying is a metal processing technique popular during the Spring and Autumn Period (770-476 B. C.) and the Warring States Period (475-221 B. C.). Patterns on the surface of the bronze figure are chiselled out and gold and silver threads (which can be as thin as hair) are inlaid. Finally the whole figure is filed and polished resulting in a splendid artistic work highlighting the different colours of the three different kinds of metal. The artifact shown here was unearthed from Ningxia'...

  8. Recent underwater explorations at Dwarka and surroundings of Okha Mandal

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Gudigar, P.; Tripati, S.; Vora, K.H.; Bandodkar, S.N.

    . This is perfectly conical in shape with a circular hole in the centre. The chisel marks in the hole were also noticed. It is made out of c onglomerate and is reddish in Fig. 3: L-shaped stonewall in Dwarka waters colour. The object appears to be unused... quantity of pottery was also noticed in intertidal zone area. Intertidal Zone Exploration Intertidal zone explorations were carried out to the north and south of the present Bet Dwarka jetty. A broken rectangular stone anchor of reddish colour...

  9. Technology and methods of making decorated balusters

    Science.gov (United States)

    Krauinsh, D.; Selivanova, A.

    2015-10-01

    Woodworking companies looking for a simple solution to simplify and speed up the whole process of making a carved balusters. Tech solution is the replacement of threaded elements solid wood balusters on plastic threaded overhead items secured by adhesive to the surface of the workpiece chiseled. This solution allows to reduce the cost of manufacturing carved balusters, without resorting to a woodcarver and using expensive equipment. Through further improvements, such as painting, patina, it turns out a product that is difficult to distinguish from solid carved balusters.

  10. Optical coherence tomography to evaluate the interaction of different edge designs of four different silicone hydrogel lenses with the ocular surface

    Directory of Open Access Journals (Sweden)

    Turhan SA

    2015-05-01

    Full Text Available Semra Akkaya Turhan, Ebru Toker Department of Ophthalmology, School of Medicine, University of Marmara, Istanbul, Turkey Purpose: To evaluate the lens edge interaction with the ocular surface with different edge designs using optical coherence tomography and to examine the effect of lens power on the lens edge interactions. Methods: Four types of silicone hydrogel lenses with different edge designs (round-, semi-round-, chisel-, and knife-edged at six different powers (+5.0, +3.0, +1.0, -1.0, -3.0, and -5.0 diopters were fitted to both eyes of 20 healthy volunteers. Optical coherence tomography images were taken at the corneal center and at the limbus within 15–30 minutes after insertion. The images were evaluated with respect to two parameters: conjunctival indentation exerted by the lens edge; and the tear film gaps between the posterior surface of the lens and the ocular surface. The amount of conjunctival indentation was measured with the distortion angle of the conjunctiva at the lens edge. Results: The degree of conjunctival indentation was highest with the chisel-edged design followed by the semi-round design (P<0.0001. Knife- and round-edged lenses exerted similar levels of conjunctival indentation that was significantly lower compared to chisel-edged lens (P<0.001. For each one of the tested lens edge designs, no significant difference was observed in the conjunctival indentation with respect to lens power. The chisel-edged lens produced the highest amount of conjunctival indentation for each one of the six lens powers (P<0.0001. Post-lens tear film gaps at the limbus were observed at most in the round-edge design (P=0.001. Conclusion: The fitting properties of contact lenses may be influenced by their edge design but not by their lens power. Keywords: Acuvue Oasys, Air Optix Aqua, PremiO, PureVision 2 HD, silicone hydrogel contact lenses

  11. MATHEMATICAL MODEL AND CALCULATING METHOD OF PARAMETERS FOR TWIST DRILL HYPERBOL

    Institute of Scientific and Technical Information of China (English)

    WangMin; ZuoDunwen; LiChao

    2002-01-01

    Mathematical model for hyperboloid grinding of twist drill and relationships between drill design and grinding parameters are introduced.Point angles at outer corner and chisel edge corner are proposed to be used as the drill design parameters to determine the type uniquely and the relicf andgle is used as a supplement parameter.Function relations between the twist drill design and the grinding parameters are derived.Hence a theeoretical basis is estab-lised for design and grinding of the hyperboloid twist drill.

  12. Reducing ploughing depth and nitrogen fertilisation in hilly environment of the centre of italy (marche

    Directory of Open Access Journals (Sweden)

    Domenico Laureti

    2007-07-01

    Full Text Available For the purpose to provide a contribution about ploughing subject three ways were compared in a quadriennal rotation from Experimental Industrial Crops Institute in Osimo. During the years 1986-1999, in a factorial experiment with 4 replications, traditional (50 cm, shallow ploughing (25 cm and chiseling (50 cm plus reduced ploughing (25 cm were compared with two crop rotations (sugar beet- wheat; shelling peas-wheat and three nitrogen levels (0, 92, 184 kg ha-1 in a split block experiment. The conventional and chiseling plus reduced ploughing did not influenced sugar-beet or peas yield or qualitative and quantitative crop traits; like it was emphasized in the previous seven years. Wheat seed yield was positively influenced by reduced ploughing done to the previous crop but not by rotation. Straw yield was higher after sugar beet than after peas. Nitrogen fertilisation allowed the best technical yield of wheat at the intermediate level of 90 kg ha-1, whereas more nitrogen (180 kg ha-1 improved only the biomass and heads per squared meter at harvesting, lowering the test weight of wheat. In conclusion we could affirm that, in this experience, the best ploughing for sugar-beet and shelling peas is at 25 cm. Moreover it was not possible to reduce fertilisation of wheat following shelling peas (leguminous crop.

  13. A standard procedure for measuring pellet hardness of rodent diets.

    Science.gov (United States)

    Thigpen, J E; Locklear, J; Romines, C; Taylor, K A; Yearby, W; Stokes, W S

    1993-10-01

    A Chatillon Model TCM-200 test stand with exchangeable flat horizontal or concave receptacle bases and a DFI-200 gauge load cell with multiple types of upper exchangeable test jaws (large round-flat, medium round-flat, chisel, bullet, and cone-shaped) were compared by using preautoclaved and autoclaved NIH-31 rodent diet pellets to determine which type of hardness testing system would give the most accurate and reproducible results for measuring pellet hardness. The type and size of the contact area of the upper jaws significantly affected the force required to break the pellets. Significant differences were observed between the flat-horizontal and concave receptacle bases in the force required to break the pellets when using the two round-flat upper jaws. In contrast, similar results were obtained with both bases when the bullet, chisel, or cone-shaped upper jaws were used. Autoclaved pellets were 69.4% (range, 49 to 94%) harder than preautoclaved pellets. These results suggest that different testing systems can be used for measuring pellet hardness and that a standard procedure must be used in order to compare pellet hardness results between different testing laboratories. It was concluded that the flat-horizontal base and the larger round-flat end upper jaw gave the most reproducible results for measuring pellet hardness. PMID:8277732

  14. Effects of foreign object damage from small hard particles on the high-cycle fatigue life of titanium-(6)aluminum-(4)vanadium

    Science.gov (United States)

    Hamrick, Joseph L., II

    Thin rectangular samples of Ti-6Al-4V were damaged by four methods to represent foreign object damage found in turbine engine blades: (1) impact with 2 mm. and 5 mm diameter glass spheres at 305 m/s, (2) impact with 2 mm and 4 mm diameter steel spheres at 305 m/s, (3) quasi-static displacement controlled indentation using steel chisels with 1 mm, 2 nun and 5 mm diameter tips and (4) shearing notches with a 2 mm. diameter chisel point under a quasi-static loading condition. Finite element analysis was used to study the relationship between the stress state created by the plastic damage and the fatigue strength. A new method of quantifying the amount of plastic damage from multiple methods was developed. The fatigue strength required for crack initiation at 10E7 cycles was found to be a function of the total depth from the edge of the undeformed specimen up to the end of the plastically deformed zone. For damage depths less than 1750 mum, the reduction in fatigue strength is proportional to the depth of total damage. For depths > 1750 mum, there appears to be a threshold value of fatigue strength.

  15. Investigations On The Influence Of Process Parameters On Damage Factor During Drilling Of Glass Fiber Reinforced Composites

    Directory of Open Access Journals (Sweden)

    R.Raja

    2011-11-01

    Full Text Available Drilling is an essential operation during the assembly of the structural frames of automobiles and aircrafts made of fiber reinforced composites. The life of a joint, especially the fatigue life depends on the quality of the hole drilled. A hole with minimum damage factor can bring forth better life and aesthetic to the joint formed. The present investigation aims at arriving at a set of cutting parameters and compositional parameters to minimize damage factor during drilling of glass fiber reinforced composites. Thespindle speed was varied at three levels namely 142, 210 and 450 RPM .The chisel angles were kept at 90,100 and110 degrees and three orientations were selected for the glass fibers namely 90 degrees, 45 degrees and random orientation. A nine run experiment was designed based on Taguchi’s technique and the experiments were carried out with five replications. It was observed that a spindle speed of 450 RPM, a chisel angle of 110 degrees and a random fiber orientation can bring forth better holes with minimum damage factor .Confirmatoryexperiments were conducted to check the validity of the predictions .The experimental results matched well with the predictions

  16. Shear Strengthening of RC Beams Using Sprayed Glass Fiber Reinforced Polymer

    Directory of Open Access Journals (Sweden)

    Sayed Mohamad Soleimani

    2012-01-01

    Full Text Available The effectiveness of externally bonded sprayed glass fiber reinforced polymer (Sprayed GFRP in shear strengthening of RC beams under quasi-static loading is investigated. Different techniques were utilized to enhance the bond between concrete and Sprayed GFRP, involving the use of through bolts and nuts paired with concrete surface preparation through sandblasting and through the use of a pneumatic chisel prior to Sprayed GFRP application. It was found that roughening the concrete surface using a pneumatic chisel and using through bolts and nuts were the most effective techniques. Also, Sprayed GFRP applied on 3 sides (U-shaped was found to be more effective than 2-sided Sprayed GFRP in shear strengthening. Sprayed GFRP increased the shear load-carrying capacity and energy absorption capacities of RC beams. It was found that the load-carrying capacity of strengthened RC beams was related to an effective strain of applied Sprayed GFRP. This strain was related to Sprayed GFRP configuration and the technique used to enhance the concrete-FRP bond. Finally, an equation was proposed to calculate the contribution of Sprayed GFRP in the shear strength of an RC beam.

  17. Quantification of Soil Physical Properties by Using X-Ray Computerized Tomography (CT) and Standard Laboratory (STD) Methods

    Energy Technology Data Exchange (ETDEWEB)

    Maria Ambert Sanchez

    2003-12-12

    The implementation of x-ray computerized tomography (CT) on agricultural soils has been used in this research to quantify soil physical properties to be compared with standard laboratory (STD) methods. The overall research objective was to more accurately quantify soil physical properties for long-term management systems. Two field studies were conducted at Iowa State University's Northeast Research and Demonstration Farm near Nashua, IA using two different soil management strategies. The first field study was conducted in 1999 using continuous corn crop rotation for soil under chisel plow with no-till treatments. The second study was conducted in 2001 and on soybean crop rotation for the same soil but under chisel plow and no-till practices with wheel track and no-wheel track compaction treatments induced by a tractor-manure wagon. In addition, saturated hydraulic (K{sub s}) conductivity and the convection-dispersion (CDE) model were also applied using long-term soil management systems only during 2001. The results obtained for the 1999 field study revealed no significant differences between treatments and laboratory methods, but significant differences were found at deeper depths of the soil column for tillage treatments. The results for standard laboratory procedure versus CT method showed significant differences at deeper depths for the chisel plow treatment and at the second lower depth for no-till treatment for both laboratory methods. The macroporosity distribution experiment showed significant differences at the two lower depths between tillage practices. Bulk density and percent porosity had significant differences at the two lower depths of the soil column. The results obtained for the 2001 field study showed no significant differences between tillage practices and compaction practices for both laboratory methods, but significant differences between tillage practices with wheel track and no-wheel compaction treatments were found along the soil

  18. Balanço de nutrientes em povoamento de Eucalyptus saligna implantado sobre Cambissolo Háplico no RS Nutrient balance in plantation of Eucalyptus saligna planted on Inceptisol in Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Michael Mazurana

    2011-09-01

    Full Text Available A fragilidade de um sistema florestal pode ser avaliada através do balanço de nutrientes, destacando a eficiência da ciclagem sendo que, em certos casos, a adubação deve ser utilizada para manter ou elevar a produtividade do sistema. Objetivou-se com este estudo avaliar o comportamento de diferentes sistemas de preparo de solo em Cambissolo Háplico e sua influência nas perdas de nutrientes transportados por erosão em área cultivada com Eucalyptus saligna. Os tratamentos foram constituídos por quatro métodos de preparo do solo: subsolagem interrompida com resíduo (SIR, subsolagem contínua com resíduo (SCR, subsolagem contínua sem resíduo (SSR e coveamento mecânico (CME, em delineamento de blocos ao acaso com três repetições por tratamento. O sistema SSR apresentou as maiores perdas de nutrientes quando comparadas com as dos outros métodos de preparo de solo. As maiores perdas de nutrientes pela erosão hídrica foram, pela ordem, K > Ca > Mg > P > Cu > B. Os sistemas de preparo SIR e SSR apresentaram os maiores teores de nutrientes contidos na parte aérea e o menor balanço nutricional, respectivamente.The forest system fragility can be evaluated through nutrient balance, with an emphasis in the cycling efficiency to maintain or elevate of productivity of system. The objective of this study was to evaluate the effects of different soil tillage systems on nutrient losses transported by erosion on an Inceptisol with Eucalyptus saligna. Four tillage systems were tested: interrupted deep chiseling with residue (SIR, continuous deep chiseling with residue (SCR, continuous deep chiseling without residue (SSR and mechanical pitting (CME. The SIR system showed the greatest nutrient losses. The loss of nutrients was higher by water erosion, in the following order, K > Ca > Mg > P > Cu > B. SIR and SSR tillage systems had the highest levels of nutrients in shoots and lower nutritional balance, respectively.

  19. Quantification of forces required for stabbing with screwdrivers and other blunter instruments.

    Science.gov (United States)

    Parmar, Kiran; Hainsworth, Sarah Victoria; Rutty, Guy Nathan

    2012-01-01

    In the UK, stabbing is the most common cause of homicide. The weapons used include knives, swords, screwdrivers and glass shards. Quantifying the exact force used in a stabbing incident is considered to be a difficult area due to the large number of variables present, such as sharpness of weapon, angle of attack and relative movements of the people involved. Having quantifiable data would allow a forensic pathologist to make a more informed decision when it comes to answering the commonly posed question in court "what was the degree of force involved in the stabbing incident?" The answer to this question is considered significant in determining an alleged assailant's intent to cause harm. This paper presents results of the first detailed study relating geometry of screwdrivers to the forces required for penetration. Additionally, a range of other blunt weapons such as pens and chisels have also been studied. A silicone rubber-foam analogue has been used as the main skin simulant owing to it having similar mechanical properties to that of human skin and giving highly repeatable results. Different screwdrivers of varying shape and size have been tested (i.e. slotted, Phillips, posidriv and Torx), along with other implements including chisels and pens. The weapon geometry was characterised and related to the peak force required for penetration. Our results show that there is a direct correlation between the cross-sectional area of a screwdriver head and the amount of force required for penetration. Screwdrivers with larger cross-sectional areas require a significantly greater force to penetrate (forces in the region of 100-120 N) but "sharper" slotted screwdrivers penetrate with much lower forces (~30 N). The forces required for penetrating the rubber-foam analogue with screwdrivers are higher than for "sharp" knives, but in some cases similar to the forces required for stabbing with "blunt" knives. For the other weapons such as chisels and biros, the force required

  20. Managing an oil spill response

    International Nuclear Information System (INIS)

    In the oil spill response business everything starts with a plan. When planning is set at only middle and top management levels before being chiseled into corporate marble, the result is all too often a plan for failure. For any chance at success, the plan must make sense to, and solve the problems of, the people at the ''business'' end of the business. In the case of Marine Spill Response Corporation (MSRC), that means highly trained responders are put at sea or along coastlines to remove oil from the water, or to deflect oil away from environmentally sensitive areas. They are fortunate in MSRC, and especially in the Gulf Coast Region, to have on their staff, some of the most knowledgeable and experienced oil spill responders in the world. The company relies on them to help build their plans, and to poke holes wherever their plans are inconsistent with getting the job done right

  1. Study on comprehensive properties of duplex austenitic surfacing alloys for impacting abrasion

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, comprehensive property crack resistance, work hardening and abrasion resistance of a series of double-phases austenitic alloys(FAW) has been studied by means of SEM, TEM and type MD-10 impacting wear test machine. FAW alloys are of middle chromium and low manganese, including Fe-Cr-Mo-C alloy,Fe-Cr-Mn-C alloy and Fe-Cr-Mn-Ni-C alloy, that are designed for working in condition of impacting abrasion resistance hardfacing.Study results show that the work hardening mechanism of FAW alloys are mainly deformation high dislocation density and dynamic carbide aging, the form of wearing is plastic chisel cutting. Adjusting the amount of carbon, nickel, manganese and other elements in austenitic phase area, the FAW alloy could fit different engineering conditions of high impacting, high temperature and so on.

  2. Soap-stone in architecture of North European cities. A nomination as a candidate for a Global Heritage Stones Resource

    Science.gov (United States)

    Bulakh, Andrey

    2016-04-01

    Soap stone represents soft Proterozoic rock type from the deposit Nunnalahti situated on the western shore of the big Lake Pielinen in Eastern Finland. It consists of talc (40 - 50 %), magnesite MgCO3 (40 - 50 %), chlorite (5 - 8 %), dolomite, calcite, etc. The colour of the stone is very spectacular and varies from yellow and brownish-yellow to grey, greenish grey. The soft stone is a highly workable material for a sculptor's chisel. It was one of the most popular ornamental rocks used architecture of the Modern style in St Petersburg, Helsinki, Turku, Tampere and other North European cities lately in the XIX-th centuries. Examples are given and discussed. References: Bulakh, A.G., Abakumova, N.B., and Romanovsky, J.V. St Petersburg: a History in Stone. 2010. Print House of St Petersburg State University. 173 p. (In English).

  3. So I Sat Down with My Mother: Connectedness Orientation and Pupils' Independence

    Science.gov (United States)

    Eklöf, Anders; Nilsson, Lars-Erik; Svensson, Peter

    Swedish educational policy underlines the importance of independence. In this paper we use socio-cultural theory and Foucault to explain how pupils’ independency is transformed into something else in their work. Our results derive from analyses of filmed sessions and entries in the pupils’ logbooks. Our findings demonstrate that the pupils’ definitions of independence differ from those of the course plan in several aspects: i) the use of certain resources is not considered to show lack of independence, ii) doing things yourself is considered being most independent and iii) to follow instructions, even if this means violating your unique personal thought, is considered a prerequisite for passing/getting good grades and as such a necessary adaption to the school context, sooner than a sign of dependency. Consequently we argue that pupil independency should be regarded as a phenomenon chiseled out within a community of practice rather than a personal capacity.

  4. Evaluation of the agricultural tractor using biofuel and diesel oil; Avaliacao de um trator agricola utilizando biocombustivel e oleo diesel

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Reny Adilmar Prestes; Pinheiro Neto, Raimundo; Meyer, Wagner; Mendonca, Elton Costa de; Roberti, Marcelo [Universidade Estadual de Maringa (UEM), PR (Brazil)], Emails: raplopes@uem.br, rpneto@uem.br

    2009-07-01

    Test with alternative fuels is essential to evaluate the performance of machines and engines. In this paper, the performance of a tractor in chiseling operation was evaluated using oil diesel and biofuel (oil diesel + soybean vegetable oil mixture). Speed of displacement, slip wheels, force traction bar and fuel consumption was evaluated in areas under tillage and no-tillage. The speed of displacement of the set presented similar behavior in tillage and no-tillage. Bigger values mean force in the bar of traction, slip and fuel consumptions had been observed for no-tillage with the tractor operating with diesel. Bigger values mean consumption the biofuel had been observed in areas under tillage. The coverings of the soil had influenced in the values of force bar traction, slip wheels, speed of displacement and fuel consumption. In the studied conditions, the tests demonstrate that the mixture oil diesel + soybean vegetable oil had not influenced in the performance of the tractor. (author)

  5. Respuesta del girasol a diferentes profundidades de incorporación del fertilizante Response of sunflower to deep fertilization

    Directory of Open Access Journals (Sweden)

    Peña C. Jorge

    1989-12-01

    Full Text Available El estudio se realizó con el objetivo de analizar la respuesta del girasol a la fertilización a diferentes profundidades. Los tratamientos fueron: incorporación del fertilizante a 10 cm con rastrillo pulidor, a 15 cm con rastra-arado, a 25 cm con arado de discos y a 30 cm con cincel-abonador; testigo absoluto sin fertilizar. Se presentaron incrementos en rendimiento a la incorporación del fertilizante a 30 cm, mostrando diferencias altamente significativas con la fertilización a 10 cm y el testigo, los incrementos en rendimiento fueron de 64.9% y 109.7% en promedio para cada uno de los semestres. Igualmente, se observaron aumentos en el diámetro del capítulo, en el peso de 1.000 semillas, en la altura de planta y disminución en el porcentaje de semillas vanas en el capitulo. Los porcentajes de cáscara, almendra, aceite y proteína no respondieron a la fertilización profunda. Desde el punto de vista económico, la mejor alternativa correspondió a la fertilización a 30 cm con cincel-abonador; la incorporación a 15 cm, con la rastra-arado, se presentó como según da opción con una tasa de retorno marginal aceptable, la cual para la región se estimó en 100 % como valor mínimo.The objective of the study was to analize the response in yield and other agronomic characteristics of sunflower based on different depths of fertilizer application. The treatments were application of fertilizer 10 cm depth tandem disk harrow, 15 cm depth with disk harrow, 25 cm depth with disk plow and 30 cm depth with chisel; an absolut control was also included. The incorporation with chisel was significantly higher than disk harrow and the control, but not with tandem disk harrow and disk plow. Increments of the chisel treatment with respect to disk harrow for the two consecutive semester were thus: for yield 64.9% and 109.7%; for capitulum diameter 20.1% and 29.9%: for weight of 1.000 seeds 34.7% and 37.1 % for plant height 15.6 % and 27.7 %, and a

  6. Late Bronze Age hoard studied by PIXE

    International Nuclear Information System (INIS)

    The hoards of metallic objects belonging to the Late European Bronze Age can be interpreted differently depending on the type, number and composition of the artefacts. PIXE analysis has been performed in nine items from the Hoard of Freixanda in Portugal comprising four socket axes, a palstave axe, a ring, a chisel, a dagger, and a casting debris. Besides the composition of the main matrix elements, that is Cu and Sn, the amount of trace elements of interest like, As, Pb, Ni, and Ag has been determined using this ion beam technique. The high tin content alloy and the high purity of the metals from the Freixanda hoard are characteristic of the Portuguese and Spanish Late Bronze Age metallurgy, supporting the idea of a regional production.

  7. Produtividade de soja e milho após coberturas de inverno e descompactação mecânica do solo Soybean and corn yield after soil winter covers and soil mechanical loosening

    Directory of Open Access Journals (Sweden)

    Henrique Debiasi

    2010-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de coberturas de inverno e da descompactação mecânica do solo sobre o desempenho de soja e milho, em sistema de plantio direto. Foram conduzidos dois experimentos em Eldorado do Sul, RS, sobre Argissolo Vermelho compactado, nas safras 2005/2006 e 2006/2007. No primeiro, o delineamento experimental foi em blocos ao acaso, com parcelas subdivididas. Os tratamentos consistiram de duas profundidades teóricas de atuação da haste sulcadora da semeadora (0,06 e 0,12 m, subparcela e de três tipos de coberturas do solo no inverno (parcela: pousio, aveia-preta (Avena strigosa e aveia-preta+ervilhaca (Vicia Sativa. Em 2006, a cobertura aveia-preta+ervilhaca foi substituída por nabo-forrageiro (Raphanus sativus. No segundo experimento, realizado em blocos ao acaso, o solo foi escarificado e os tratamentos consistiram do uso de aveia-preta ou nabo-forrageiro como cobertura de inverno. Os cultivos de cobertura reduziram a compactação superficial do solo (0-0,06 m em comparação ao pousio e, na safra 2006/2007, sob condições de baixa disponibilidade hídrica, proporcionaram maior produtividade de milho e soja. Isso não se repetiu em 2006/2007, quando a disponibilidade hídrica foi adequada. O aumento da profundidade de atuação das hastes sulcadoras não influenciou a produtividade da soja e do milho. A escarificação reduziu a produtividade da soja e do milho em relação ao SPD contínuo.The objective of this work was to evaluate the effect of soil winter covers and soil mechanical loosening on soybean and corn yield, in no-tillage system. Two experiments were carried oud in Rio Grande do Sul state, Brazil, in a compacted Argissolo Vermelho (Haplic Acrisol, in the 2005/2006 and 2006/2007 crop seasons. The first experiment was carried out in a complete block design, with a split plot arrangement. The treatments were two theoretical working depths of a driller chisel-type furrow opener (0.06 and 0

  8. Radiological aspects of choice of a system of cultivation of sod-podzolic sandy loam soils with different degree of humidity on lands of Mogilev region contaminated with 137Cs

    International Nuclear Information System (INIS)

    In the conditions of the Republic of Belarus there were presented data about the influence of technological factors on entry of 137Cs into plant products (grain and green mass). In course of the study there were analyzed the following variants of soil cultivation: moldboard plowing; subsurface chisel soil tillage; subsurface surface soil tillage; minimal tillage. There were presented data on specific activity of 137Cs in plant product samples of oat (Avena sativa) grain; field pea (Pisum arvense L.) and oat mixture grain and green mass; wheat (Triticum aestivum) grain. There were determined the main principles of influence of cultivation systems of sod-podzolic sandy loam soil with different degree of humidity on transition of 137Cs into plants depending on the degree of soil and crop humidity. On the automorphic soil there was revealed a tendency of increased transition of 137Cs into grain and green mass after application of subsurface surface soil tillage system

  9. Comparison of the Effects of No Tillage, Minimum Tillage and Conventional Tillage on Dry Land Wheat Yield in Pebbly Field in Tropical Region

    Directory of Open Access Journals (Sweden)

    N Loveimi

    2016-04-01

    Full Text Available The current study was conducted to compare different tillage methods on wheat yield in pebbly dry land areas done within three years (2006-2008 in north Khouzestan (Baghmalek city in randomized block design with five treatments and four replications. The experimental treatments were:(1chisel plow +seed-drill, (2Semi plow(mold board plow with remove mold board+seed-drill, (3no-till-drill, (4sweep plow +seed-drill and (5conventional method(mold board plow+ broadcasting seed and fertilizer+ sweep plow. These treatments included minimum tillage (treatments 1, 2 and 4, no tillage (treatment 3 and conventional tillage (treatment 5. Complex variance analyses of three years data showed that there was no significant difference between tillage methods and interaction of tillage methods with year in soil moisture content in different plant growth stages (stem, flowering, and filling seeds stages but years were different in this factor. Variance analyses of data showed that there was no significant difference between different tillage methods in percent of organic materials in different soil depths in the end of the project. However, no difference in tillage methods in the amount of organic material has been analyzed based on the pebbly conditions. The complex variance analyses of data also showed that tillage methods had significant effect on grain yield and other agronomical factors, except plant height and harvest index. According to the results any devices cause to back more gravel and cobblestone into sub soil layer provide more grain yield. Therefore, mold board plow resulted in maximum yield in three experimental years which were different in amount and distribution of rainfall, and also in third year the amount of rainfall was considerably low. The grain yield averages of three years were 1333, 1558, 1190, 1080 and 1787 Kg.ha-1 for chisel plow, semi plow, no-till-drill, sweep plow and mold board plow respectively.

  10. The Impact of Various Types of Tillage on the Soil Water Availability

    Directory of Open Access Journals (Sweden)

    BESNIK GJONGECAJ

    2014-07-01

    Full Text Available The present study is focused on the role that various ways of soil tillage may have on the increase of soil water availability to the plant roots. The research was carried out in Tirana, Albania, and the experiment was established in a vineyard field. The soil was cultivated in three different ways (three treatments: conventional (plowing plus surface cultivation, conservative (subsoiling plus surface cultivation, conservative (chisel plowing plus surface cultivation. In order to quantify the available soil water to plants, the pF-soil moisture curves were determined. The determined pF-soil moisture curves belong to two layers: 0-25 cm and 25-50 cm, taken into consideration for each treatment. The soil water content between the field capacity (FWC and the permanent wilting point (PWP was considered as potentially available to plant roots. The results showed clearly that the way the tillage was applied has a significant effect on soil water capacity potentially available to plant roots. Loosening the soil by breaking up the impermeable layers, the conservative tillage makes possible the increase of the amount of water held by soil particles in the range between FWC and PWP, in comparison with the conventional tillage. This increase of available soil water capacity is due to the soil loosening in deeper layers of soil profile as well, which leads to the situation where the plant roots can penetrate deeper and occupy more space, consequently, drawing more water to meet their needs. Within the conservative tillage versions, sub soiling seems to be more effective in the increase of available soil water capacity comparing with the chisel plowing. The study contributes, as well, to the determination of the pF-soil moisture curves in a way that is theoretically well based. The founded curves fit with the exponential form of functions and the coefficients of determinations, for each case under study, are significant in high probability levels.

  11. Water erosion during a 17-year period under two crop rotations in four soil management systems on a Southbrazilian Inceptisol

    Science.gov (United States)

    Bertol, Ildegardis; Vidal Vázquez, Eva; Paz Ferreiro, Jorge

    2010-05-01

    Soil erosion still remains a persistent issue in the world, and this in spite of the efforts to ameliorate soil management systems taken into account the point of view of environmental protection against soil losses. In South Brazil water erosion is mainly associated to rainfall events with a great volume and high intensity, which are more or less evenly distributed all over the year. Nowadays, direct drilling is the most widely soil management system used for the main crops of the region. However, some crops still are grown on conventionally tilled soils, which means mainly ploughing and harrowing and less frequently chisel ploughing. In Lages-Santa Catarina State, Brazil, a plot experiment under natural rain was started in 1992 on an Inceptisol with the aim of quantifying soil and water losses. Treatments included bare and vegetated plots. The crop succession was: oats (Avena strigosa), soybean (Glycine max), vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and beans (Phaseolus vulgaris). Soil tillage systems investigated in this study were: i) conventional tillage (CT), ii) reduced tillage (MT), iii) no tillage (NT) under crop rotation and iv) conventional tillage on bare soil (BS). Treatments CT and BS involved ploughing plus twice harrowing, whereas MT involved chisel ploughing plus harrowing. Rainfall erosivity from January 1 1992 to December 31 2009 was calculated. Soil losses from the BS treatment along the 17 year study period were higher than 1200 Mg ha-1. Crop cover significantly reduced erosion, so that under some crops soil losses in the CT treatment were 80% lower than in the BS treatment. In turn soil losses in the MT treatment, where tillage was performed by chiselling and harrowing, were on average about 50% lower than in the CT treatment. No tillage was the most efficient soil management system in reducing soil erosion, so that soil losses in the NT treatment were about 98% lower than in the BS treatment. The three

  12. Soil Carbon Changes in Transitional Grain Crop Production Systems in South Dakota

    Science.gov (United States)

    Woodard, H. J.

    2004-12-01

    Corn-C (Zea Mays L.), soybean-S (Glycine max L.) and spring wheat-W (Triticum aestivum L.) crops were seeded as a component of either a C-S, S-W, or C-S-W crop rotation on silt-loam textured soils ranging from 3.0-5.0% organic matter. Conservation tillage(chisel plow-field cultivator) was applied to half of the plots. The other plots were direct seeded as a no-till (zero-tillage) treatment. Grain yield and surface crop residues were weighed from each treatment plot. Crop residue (stover and straw) was removed from half of the plots. After four years, soil samples were removed at various increments of depth and soil organic carbon (C) and nitrogen (N) was measured. The ranking of crop residue weights occurred by the order corn>>soybean>wheat. Surface residue accumulation was also greatest with residue treatments that were returned to the plots, those rotations in which maize was a component, and those without tillage. Mean soil organic carbon levels in the 0-7.5cm depth decreased from 3.41% to 3.19% (- 0.22%) with conventional tillage (chisel plow/field cultivator) as compared to a decrease from 3.19% to 3.05% (-0.14%) in plots without tillage over a four year period. Organic carbon in the 0-7.5cm depth decreased from 3.21% to 3.01% (- 0.20%) after residue removed as compared to a decrease from 3.39% to 3.23% (-0.17%) in plots without tillage applied after four years. The soil C:N ratio (0-7.5cm) decreased from 10.63 to 10.37 (-0.26 (unitless)) in the tilled plots over a four-year period. Soil C:N ratio at the 0-7.5cm depth decreased from 10.72 to 10.04 (-0.68) in the no-till plots over a four year period. Differences in the soil C:N ratio comparing residue removed and residue returned were similar (-0.51 vs. -0.43 respectively). These soils are highly buffered for organic carbon changes. Many cropping cycles are required to determine how soil carbon storage is significantly impacted by production systems.

  13. Carbon supply and storage in tilled and nontilled soils as influenced by cover crops and nitrogen fertilization.

    Science.gov (United States)

    Sainju, Upendra M; Singh, Bharat P; Whitehead, Wayne F; Wang, Shirley

    2006-01-01

    Soil carbon (C) sequestration in tilled and nontilled areas can be influenced by crop management practices due to differences in plant C inputs and their rate of mineralization. We examined the influence of four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)], biculture of legume and nonlegume (vetch and rye), and no cover crops (or winter weeds)} and three nitrogen (N) fertilization rates (0, 60 to 65, and 120 to 130 kg N ha(-1)) on C inputs from cover crops, cotton (Gossypium hirsutum L.), and sorghum [Sorghum bicolor (L.) Moench)], and soil organic carbon (SOC) at the 0- to 120-cm depth in tilled and nontilled areas. A field experiment was conducted on Dothan sandy loam (fine-loamy, siliceous, thermic Plinthic Paleudults) from 1999 to 2002 in central Georgia. Total C inputs to the soil from cover crops, cotton, and sorghum from 2000 to 2002 ranged from 6.8 to 22.8 Mg ha(-1). The SOC at 0 to 10 cm fluctuated with C input from October 1999 to November 2002 and was greater from cover crops than from weeds in no-tilled plots. In contrast, SOC values at 10 to 30 cm in no-tilled and at 0 to 60 cm in chisel-tilled plots were greater for biculture than for weeds. As a result, C at 0 to 30 cm was sequestered at rates of 267, 33, -133, and -967 kg C ha(-1) yr(-1) for biculture, rye, vetch, and weeds, respectively, in the no-tilled plot. In strip-tilled and chisel-tilled plots, SOC at 0 to 30 cm decreased at rates of 233 to 1233 kg C ha(-1) yr(-1). The SOC at 0 to 30 cm increased more in cover crops with 120 to 130 kg N ha(-1) yr(-1) than in weeds with 0 kg N ha(-1) yr(-1), regardless of tillage. In the subtropical humid region of the southeastern United States, cover crops and N fertilization can increase the amount of C input and storage in tilled and nontilled soils, and hairy vetch and rye biculture was more effective in sequestering C than monocultures or no cover crop. PMID:16825471

  14. Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

    Science.gov (United States)

    Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

    2009-01-01

    The term "rotary percussive auto-gopher" denotes a proposed addition to a family of apparatuses, based on ultrasonic/ sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive autogopher, the emphasis would be on developing an apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses. To recapitulate from the prior articles about USDCs: A USDC can be characterized as a lightweight, low-power jackhammer in which a piezoelectrically driven actuator generates ultrasonic vibrations and is coupled to a tool bit through a free mass. The bouncing of the free mass between the actuator horn and the drill bit converts the actuator ultrasonic vibrations into sonic hammering of the drill bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary rotary drilling, ordinary hammering, or ordinary steady pushing. The predecessor of the rotary percussive auto-gopher is an apparatus, now denoted an ultrasonic/sonic gopher and previously denoted an ultrasonic gopher, described in "Ultrasonic/ Sonic Mechanism for Drilling and Coring" (NPO-30291), NASA Tech Briefs Vol. 27, No. 9 (September 2003), page 65. The ultrasonic/sonic gopher is intended for use mainly in acquiring cores. The name of the apparatus reflects the fact that, like a

  15. Seeding quality and soybean yields from using different furrowers and operation speedsQualidade de semeadura e produtividade da soja sob diferentes sulcadores e velocidades de operação

    Directory of Open Access Journals (Sweden)

    Alcir José Modolo

    2012-12-01

    Full Text Available The sowing process for annual no-till crops affects the physical soil conditions around the seeds by exposing them to adverse conditions that may limit initial plant development and reduce potential yield. The use of seed drills that are not compatible with field conditions and the use of inappropriate seed drill speeds affect sowing performance. Therefore, this study aims to evaluate the effect of different seed drill types and operating speeds on soybean quality parameters and yield components. Two furrow opener (double disc and chisel and four operating speed (0.86; 1.22; 1.47 and 1.94 m s-1 treatments were used. The following variables were evaluated: mean number of days until emergence, plant distribution uniformity, sowing depth, area of the soil disturbed, crop stand and grain yield. Overall, the chisel furrow opener provided a greater sowing depth and increased the disturbed soil area more than the double disc furrow opener. Increased operating speeds reduced crop stands and yields and increased the disturbed soil area. Em culturas anuais submetidas ao sistema plantio direto o processo de semeadura afeta o condicionamento físico do solo ao redor das sementes expondo as mesmas a condições adversas, podendo limitar o desenvolvimento inicial das plantas e minimizar o potencial produtivo. O uso de sulcadores não condizentes com a situação de campo e de velocidades inadequadas são fatores que afetam o bom desempenho da semeadura. Nesse contexto, este trabalho teve por objetivo, avaliar o efeito de diferentes sulcadores e velocidades de operação sobre parâmetros de qualidade de semeadura e componentes de produtividade da cultura da soja. Os tratamentos foram compostos pela combinação entre dois sulcadores (disco e haste e quatro velocidades de operação (0,86; 1,22; 1,47 e 1,94 m s-1. Foram avaliados: o número médio de dias para a emergência, a uniformidade de distribuição de plantas, a profundidade de semeadura, a área de

  16. Reduced tillage for tobacco (Nicotiana tabacum L. production in East Cuba. Soil physical properties and crop yield

    Directory of Open Access Journals (Sweden)

    Yosvel E. Olivet

    2014-06-01

    Full Text Available The area devoted to growing tobacco (Nicotiana tabacum L. in the province of Granma, Cuba, accounted for nearly 2600 ha in the year 1997, which represented the 4% of the total tobacco plantation area on the island in that year. Tobacco is tillage-intensive since traditional production systems entail seven or eight cultivation operations before transplanting. The objective of this study was to evaluate two alternative tillage systems in comparison with conventional tillage for tobacco production with the aim to improve soil conditions, reduce the number of tillage operations for soil preparation for transplanting, and increase yields. The treatments studied were: (T1 conventional or traditional tillage, (T2 reduced tillage with a multi-tiller plough, and (T3 reduced tillage with a chisel plough. T1 consisted in disc ploughing twice and disc harrowing twice for primary tillage, while before transplanting plots were ploughed twice with a horse-drawn mouldboard plough and harrowed twice with a horse-drawn spike-tooth harrow. In T2 primary tillage was accomplished with two passes with the multi-tiller followed by disc harrowing twice before transplanting. In T3 chisel ploughing was substituted for multi-tiller ploughing. The two reduced tillage systems improved the physical conditions of the soil, which resulted in: lower bulk density, with average values across the 0-30 cm soil profile of 1.48, 1.34 and 1.30 Mg m-3 in T1, T2 and T3, respectively, at the end of the growing season; higher soil water content in the soil profile in all four sampling dates per season; greater porosity; and lower resistance to penetration with values of 2.48, 2.15 and 1.71 MPa in T1, T2 and T3, respectively, before crop harvesting. Tillage system T3 provided the highest crop yields (2.26 Mg ha-1 compared with T2 (2.14 Mg ha-1 and T1 (1.95 Mg ha-1, for the plants grown on T3 plots had the largest number of leaves. The size of the leaves was similar in all three systems

  17. Influence of Reduced Tillage and Green Manures on Weeds in Organic Farming

    Directory of Open Access Journals (Sweden)

    Grosse, Meike

    2014-02-01

    Full Text Available Reduced tillage and green manures may be capable to further improve organic crop production systems, if they are adapted to the specific needs of organic farming. One goal of the European research project TILMAN ORG (www.tilman-org.net is to develop a more efficient weed management with at the same time increased biodiversity through improved use of green manures in different systems of reduced tillage. The results of a repeated one year trial on “Domaene Frankenhausen”, the research farm of University of Kassel, regarding the effect of both leguminous and non-leguminous green manures on weeds in four different tillage systems is the main topic of this paper. After the green manure species Sinapis alba, Trifolium resupinatum and Vicia sativa and a bare fallow as a control the main crop oat was sown in four different tillage systems: plough, chisel (2012 respectively disc harrow (2013, mulching + drilling and direct drilling. 2012 weed cover was generally low in the plough system compared to the other tillage systems. In the mulching + drilling- and direct drilling- systems the plots after the green manure species S. alba and T. resupinatum and the bare fallow had to be given up because weed pressure was too high. Compared to that V. sativa was able to suppress weeds considerably better and resulted in similar yields to the plough and chisel treatments 2012 on a level from 55.3 dt ha-1 to 59.1 dt ha-1. 201all mulching + drilling- and direct drillingplots had to be given up because of too high weed pressure. The weed pressure in the disc harrow – system differed not significantly from the plough system, but only green manure species Vicia sativa resulted in similar oat yields compared to the plough treatments (V. sativa x disc harrow 56.2 dt ha-1, V. sativa x plough 53.9 dt ha-1. In the plough – treatments there was an overall low weed pressure. Concerning yield there were no significant differences regarding green manure treatment.

  18. A preliminary study on 3D reconstruction and extracting mandibular first molar by dint of high-speed air turbine handpiece based on rapid prototyping%数控拔牙技术的实验研究

    Institute of Scientific and Technical Information of China (English)

    刘小明; 李健俫; 王建民; 张志光; 陈隆福; 陈贵丰; 黄湘穗

    2012-01-01

    目的 探讨牙颌数字化三维重建技术与快速成型技术、数控技术相结合,实现微创和自动化拔牙的可行性.方法 锥形束CT(cone beam computed tomography,CBCT)扫描下颌牙颌标本,获得数据.采用Mimics软件重建牙颌三维实体模型,Magics软件进行数据修补.选取左侧下颌第一磨牙三维立体数据,快速成型软件切片、UG软件数据转换,导入自行研制的数控拔牙机,严格坐标定位后磨除左侧下颌第一磨牙.结果 建立了良好的三维牙颌模型,用数控拔牙机成功磨除左侧下颌第一磨牙.结论 牙颌数字化三维重建技术与快速成型技术、数控技术相结合,应用于数控拔牙机拔除标本牙是可行的.%Objective A new technique combined with digital dental teeth, 3D reconstruction from cone beam computed tomography ( CBCT) data and rapid prototyping is presented, in order to solve the difficulties of tooth extracting by traditional chisel. Methods Software Mimics and Magics were used to reconstruct three dimensional model from CT image scanned by DCTPRo CBCT with 0.2 mm slice thickness. The achievement can be applied to accomplish tooth extracting by high-speed air turbine handpiece based on rapid prototyping. Results Mandibular first molar was extracted by dint of high-speed air turbine handpiece based on rapid prototyping. Conclusion The new technique combined with digital dental teeth and rapid prototyping can be used to solve the difficulties of the tooth extracting by traditional chisel.

  19. Shadow analysis of soil surface roughness compared to the chain set method and direct measurement of micro-relief

    Directory of Open Access Journals (Sweden)

    R. García Moreno

    2010-02-01

    Full Text Available Soil surface roughness (SSR is an excellent indicator of soil susceptibility to wind and water erosion and plays an important role in the development and the maintenance of soil biota. Several methods have been developed to characterise SSR based on different methods of acquiring data. Because the main problems related to these methods involve the use and handling of equipment in the field, the present study aims to fill the need for a method for measuring SSR that is more reliable, low-cost and convenient in the field than traditional field methods. Shadow analysis, which interprets micro-topographic shadows, is based on the principle that there is a direct relationship between the soil surface roughness and the shadows cast by soil structures under fixed sunlight conditions. SSR was calculated with shadows analysis in the laboratory using hemispheres of different diameter with a diverse distribution of known altitudes and a surface area of 1 m2.

    Data obtained from the shadow analysis were compared to data obtained with the chain method and simulation of the micro-relief. The results show a relationship among the SSR calculated using the different methods. To further improve the method, shadow analysis was used to measure the SSR in a sandy clay loam field using different tillage tools (chisel, tiller and roller and in a control of 4 m2 surface plots divided into subplots of 1 m2. The measurements were compared to the data obtained using the chain set and pin meter methods. The SSR measured was the highest when the chisel was used, followed by the tiller and the roller, and finally the control, for each of the three methods. Shadow analysis is shown to be a reliable method that does not disturb the measured surface, is easy to handle and analyse, and shortens the time involved in field operations by a factor ranging from 4 to 20 compared to well known techniques such as the chain set and pin meter

  20. Energy Demand And Corn Yield With Fertilizer Application Before Sowing In Two Soil Tillage Systems; Demanda energetica e produtividade da cultura do milho com adubacao de pre-semeadura em dois sistemas de manejo do solo

    Energy Technology Data Exchange (ETDEWEB)

    Bertolini, Erick Vinicius [Universidade Estadual Paulista (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Pos-Graduacao em Agronomia], E-mail: erickbertolini@yahoo.com.br; Gamero, Carlos Antonio [Universidade Estadual Paulista (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Dept. de Engenharia Rural], E-mail: gamero@fca.unesp.br

    2010-07-01

    This study was conducted to evaluate the corn yield with fertilizer application before sowing and provide of the energy demand results involved in the fertilizer application before sowing and sowing in two soil tillage systems. The experiment was carried out at Faculdade de Ciencias Agronomicas (FCA), Universidade Estadual Paulista (UNESP), Botucatu-SP campus, from November 2006 to April 2007, in a Dystric Nitosol. The experimental design was in randomized blocks with split-plots and four repetitions. The main plots consisted in two soil tillage systems (no-tillage and reduced tillage with chisel plow) and the split-plots of fertilizer application methods (surface fertilizer application before corn sowing and fertilizer application conventional). Obtained results were analyzed by Tukey test at 5% of probability for comparing averages. Statistical analysis showed that fertilizer application before corn sowing the soil tillage systems did not influence the traction force, bar power demanded, effective field capacity, demanded time, energy specific consumption and hourly fuel consumption; the reduced tillage showed higher area fuel consumption. For corn sowing it was observed that no-tillage system showed lower traction force, bar power demanded, energy specific consumption, hourly and area consumption of fuel. Fertilizer application before corn sowing did not affect corn yield in relation to the fertilizer application conventional. (author)

  1. Identification of Gene Modules Associated with Low Temperatures Response in Bambara Groundnut by Network-Based Analysis.

    Science.gov (United States)

    Bonthala, Venkata Suresh; Mayes, Katie; Moreton, Joanna; Blythe, Martin; Wright, Victoria; May, Sean Tobias; Massawe, Festo; Mayes, Sean; Twycross, Jamie

    2016-01-01

    Bambara groundnut (Vigna subterranea (L.) Verdc.) is an African legume and is a promising underutilized crop with good seed nutritional values. Low temperature stress in a number of African countries at night, such as Botswana, can effect the growth and development of bambara groundnut, leading to losses in potential crop yield. Therefore, in this study we developed a computational pipeline to identify and analyze the genes and gene modules associated with low temperature stress responses in bambara groundnut using the cross-species microarray technique (as bambara groundnut has no microarray chip) coupled with network-based analysis. Analyses of the bambara groundnut transcriptome using cross-species gene expression data resulted in the identification of 375 and 659 differentially expressed genes (pHeuristic Cluster Chiseling Algorithm resulted in 6 and 7 gene modules in sub-optimal and very sub-optimal temperature stresses being identified, respectively. Modules of sub-optimal temperature stress are principally enriched with carbohydrate and lipid metabolic processes, while most of the modules of very sub-optimal temperature stress are significantly enriched with responses to stimuli and various metabolic processes. Several transcription factors (from MYB, NAC, WRKY, WHIRLY & GATA classes) that may regulate the downstream genes involved in response to stimulus in order for the plant to withstand very sub-optimal temperature stress were highlighted. The identified gene modules could be useful in breeding for low-temperature stress tolerant bambara groundnut varieties. PMID:26859686

  2. Surgical Management of Calcified Hydatid Cysts of the Liver

    Science.gov (United States)

    Tzardinoglou, E.; Kosmidis, Ch.; Katsohis, K.; Aletras, O.

    1999-01-01

    Hydatid disease of the liver is still a major cause of morbidity in Greece. Beside the common complications of rupture and suppuration, calcification of the hepatic cysts represent a not well studied, less frequent and sometimes difficult surgical problem. In the present study 75 cases with calcified symptomatic liver echinococcosis were operated on in the 1st Propedeutic Surgical Clinic between 1964 to 1996. Twenty-eight patients were male and 47 female with ages from 23 to 78 years. The diagnosis was based mainly on the clinical picture and radiological studies. In 5 cases the operative method was cystopericystectomy. We performed evacuation of the cystic cavity and partial pericystectomy and primary closure of the residual cavity in 6 cases, omentoplasty or filling of the residual cavity with a piece of muscle of the diaphragm in 4 cases and external drainage by closed tube, in 60 cases. In 12 of those with drainage, after a period of time, a second operation with easy, removal of most of the calcareous wall plaques was performed. The mortality rate was 2%. Our results could be considered satisfactory. In the calcified parasitic cysts of the liver the proposed technique is cystopericystectomy. An alternative procedure is pericystectomy and drainage with a “planned” reoperation with a bloodless, due to intervening inflammation, chiseling of the calcification. PMID:10468117

  3. Corn stover harvest increases herbicide movement to subsurface drains: RZWQM simulations

    Science.gov (United States)

    Shipitalo, Martin J.; Malone, Robert W.; Ma, Liwang; Nolan, Bernard T.; Kanwar, Rameshwar S.; Shaner, Dale L.; Pederson, Carl H.

    2016-01-01

    BACKGROUND Crop residue removal for bioenergy production can alter soil hydrologic properties and the movement of agrochemicals to subsurface drains. The Root Zone Water Quality Model (RZWQM), previously calibrated using measured flow and atrazine concentrations in drainage from a 0.4 ha chisel-tilled plot, was used to investigate effects of 50 and 100% corn (Zea mays L.) stover harvest and the accompanying reductions in soil crust hydraulic conductivity and total macroporosity on transport of atrazine, metolachlor, and metolachlor oxanilic acid (OXA). RESULTS The model accurately simulated field-measured metolachlor transport in drainage. A 3-yr simulation indicated that 50% residue removal decreased subsurface drainage by 31% and increased atrazine and metolachlor transport in drainage 4 to 5-fold when surface crust conductivity and macroporosity were reduced by 25%. Based on its measured sorption coefficient, ~ 2-fold reductions in OXA losses were simulated with residue removal. CONCLUSION RZWQM indicated that if corn stover harvest reduces crust conductivity and soil macroporosity, losses of atrazine and metolachlor in subsurface drainage will increase due to reduced sorption related to more water moving through fewer macropores. Losses of the metolachlor degradation product OXA will decrease due to the more rapid movement of the parent compound into the soil.

  4. NANOROBOTICS IN ADVANCES IN PHARMACEUTICAL SCIENCES

    Directory of Open Access Journals (Sweden)

    DEEPA R. PARMAR

    2010-06-01

    Full Text Available Nanorobotics is the technology of creating machines or robots at or close to the scale of a nanometre (10-9 metres, machines constructed at the molecular level (nanomachines may be used to cure the human body of its various ills. This application of nanotechnology to the field of medicine is commonly called as nanomedicine.Nanotechnology promises futuristic applications such as microscopic robots that assemble other machines or travel inside the body to deliver drugs or do microsurgery. Taking inspiration from the biological motors of living cells, chemists are learning how to utilize protein dynamics to power microsize and nanosize machines with catalytic reactions. Nanorobot?s toolkit contains features like medicine cavity containing medicine, probes, knives and chisels to remove blockages and plaque, microwave emitters and ultrasonic signal generators to destroy cancerous cells, two electrodes generating an electric current, heating the cell up until it dies, powerful lasers could burn away harmful material like arterial plaque.To cure skin diseases, a cream containing nanorobots may be used which remove the right amount of dead skin, remove excess oils, add missing oils, apply the right amounts of natural moisturising compounds, and even achieve the elusive goal of ’deep pore cleaning’.other fields of applications are to clean the wounds,to break the kidney stones, to treat gout, for parasite removal, for cancer treatment, treatment of arteriosclerosis.

  5. 黑龙江友谊县凤林古城址的发掘%Excavation on the Ancient Fenglin City-site in Youyi County, Heilongjiang

    Institute of Scientific and Technical Information of China (English)

    黑龙江省文物管理委员会

    2004-01-01

    In 2001, the Heilongjiang Provincial Commission for the Preservation of Ancient Monuments carried out survey and excavation on the Fenglin city-site. The unearthed remains can be divided into two phases. The early remains include house-foundations, as well as pottery jars, single-handle jars and balls and jade cicadas. The late vestiges are house-foundations, ash-pits and city-wall ruins. Among the objects from Phase Ⅱ, the pottery consists of jars, bowls, dou stemmed vessels, zeng steamers, cups, spindle whorls, net weights and sculptures. The stone implements embrace axes,knives, grindstones, querns and tubes; the bone artifacts belong to the types of arrowhead, hairpin, belt buckle, chisel-shaped object, oracle bone, etc. The bronzes fall into gilt buttons, ornamental tubes, finger rings, loops and belt buckles; and the ironware, into knives, needles, arrowheads, awls, fishhooks and plates of armor. In addition, there are a number of animal bones, which belong to the wild boar, ox,deer, cat, antelope, roe deer, musk deer, dog and fish. The excavation results reveal the distinctive structural forms of the city and its walls and houses, and suggest that the site represents a new cultural type.

  6. Treatment of Uranium-Contaminated Concrete for Reducing Secondary Radioactive Waste

    International Nuclear Information System (INIS)

    A volume reduction of the concrete waste by appropriate treatment technologies will decrease the amount of waste to be disposed of and result in a reduction of the disposal cost and an enhancement of the efficiency of the disposal site. Our group has developed a decontamination process for uranium-contaminated (U-contaminated) concrete, and some experiments were performed to reduce the second radioactive waste. A decontamination process was developed to remove uranium from concrete waste. The yellow or brown colored surface of the wall brick with high concentration of uranium was removed by a chisel until the radioactivity of remaining block reached less than 1 Bq/g. The concrete waste coated with epoxy was directly burned by an oil flame, and the burned surface was then removed using the same method as the treatment of the brick. The selective mechanical removal of the concrete block reduced the amount of secondary radioactive waste. The concrete blocks without an epoxy were crushed to below 30 mm and sifted to 1 mm. When the concrete pieces larger than 1 mm were sequentially washed with a clear recycle solution and 1.0 M of nitric acid, their radioactivity reached below the limit value of uranium for self-disposal. For the concrete pieces smaller than 1 mm, a rotary washing machine and electrokinetic equipment were also used

  7. Clinical study of toe ulcer and necrosis of the apex of the distal phalanx in 53 cattle

    International Nuclear Information System (INIS)

    Clinical signs, causative factors, radiographic findings, type and duration of treatment or reason for killing were evaluated in 53 cattle (mean age: 5.3 years) suffering from toe ulcer and/or apical pedal bone necrosis. A total of 78 claws were affected. Four cattle suffered from a toe ulcer in one claw, 35 cattle showed osteolysis of the apex of the distal phalanx in a single claw and 14 cattle in two or three claws per cow. Overtrimming by means of a grinding disc and/or perforation of the sole was diagnosed as the major cause in 27 cattle (49%), laminitis in 30.2% and traumatic injuries in 11.3%. Radiography revealed a varying degree of osteolysis involving up to two-thirds of the pedal bone. Twenty-one cattle (39.6%) showing multiple toe disorders or involvement of one single claw with concurrent internal diseases were destroyed. In 23 cattle, the osteolytic bone was resected using a bone curette or hammer and chisel. Of these, the treatment was successful in 20 animals. The healing period ranged from 16-60 days when one claw was affected and from 43-53 days when two claws were affected. In five cattle, the digit was amputated

  8. Culture-independent methods to study subaerial biofilm growing on biodeteriorated surfaces of stone cultural heritage and frescoes.

    Science.gov (United States)

    Cappitelli, Francesca; Villa, Federica; Polo, Andrea

    2014-01-01

    Actinobacteria, cyanobacteria, algae, and fungi form subaerial biofilm (SAB) that can lead to material deterioration on artistic stone and frescoes. In studying SAB on cultural heritage surfaces, a general approach is to combine microscopy observations and molecular analyses. Sampling of biofilm is performed using specific adhesive tape and sampling of SAB and the substrate with sterile scalpels and chisels. Biofilm observations are carried out using optical and scanning electron microscopy. Specific taxa and EPS in biofilm can be readily visualized by fluorochrome staining and subsequent observation using fluorescence or confocal laser scanning microscopy. The observation of cross sections containing both SAB and the substrate shows if biofilm has developed not only on the surface but also underneath. Following nucleic acid extraction, 16S rRNA gene sequencing is used to identify bacterial taxa, while 18S rRNA gene and internal transcribed spacer (ITS) sequence analysis is used to study eukaryotic groups. In this chapter, we illustrate the protocols related to fluorescence in situ hybridization (FISH), scanning electron microscopy (SEM), and denaturing gradient gel electrophoresis (DGGE). PMID:24664845

  9. Compensation of equipment housing elements of reactor units with heavy liquid metal coolant vessel temperature deformations

    International Nuclear Information System (INIS)

    In Russia a lot of different versions of fast reactors (FRs) are investigated and one of these is FR cooled by liquid lead and liquid lead-bismuth alloy. In this poster we are interested by FR with concrete vessel; its components are placed in cavities inside the vessel, and connected by a channel system. During the installation the equipment components are placed in several equipment housings. Between these housings there are cavities with coolant. The alignment of the housings should be provided. It can be broken by irregular concrete vessel heating during FR starting or other transition regimes. Our goal is to suggest a list of designing steps to compensate temperature deformations of equipment housing elements. A simplified model of equipment housing was suggested. It consists of two cylinders - tunnels in the concrete vessel, separated by a cavity filled by coolant and inert gas. The bottom part was considered as heated to 420 C. degrees while in the top part temperature decreased to 45 C. degrees (on the concrete surface). According to this data, results show that temperature gradient leads to a concrete layer dislocation of about 12.5 mm, which can lead to damage and breaking alignment. We propose the following solution to compensate for temperature deformation: -) to chisel out part of the upper top of the insulating concrete; -) to install an adequate misalignment of equipment housing elements preliminary; and -) to use a torsion system like a piston-type device for providing additional strength in order to compensate deformation and vibrations

  10. Wear investigations of tools used in bone surgery

    Directory of Open Access Journals (Sweden)

    J. Marciniak

    2007-01-01

    Full Text Available Purpose: The main aim of the work was evaluation of wear rate of surgical drills used in orthopaedic procedureswith the use of plate bone stabilizers.Design/methodology/approach: The authors proposed a wear evaluation methodology of surgical drill edges.The drill wear was evaluated on the basis of measurement of point angle (2 κ and wear land (VBB i VBBmax.The measurements were recorded for preselected number of holes n drilled in a bovine femur. Furthermore,structure investigations and hardness tests of surgical drills were performed.Findings: The investigations revealed diverse wear of the surgical drills. The main mechanism was the wear ofthe chamfered corner and chisel edge of the drills.Research limitations/implications: The improvement of service life of surgical drills can be achieved by thecorrect selection of heat treatment parameters, ensuring the desired geometry of edge and deposition of layerwhich ensure the significant increase of cutting edge hardness.Originality/value: The proposed methodology applied for surgical drills is an effective way of service lifeestimation. The quality of surgical tools influences the safety and the effectiveness of surgical procedures withthe use of plate stabilizers.

  11. Archaeology of Chilean pre-hispanic pieces using induced x-ray fluorescence

    International Nuclear Information System (INIS)

    Full text: One of the most famous archaeological sites of Chile is San Pedro de Atacama in the north Andean highlands. The site, 68.23 W, 22.89 S, is close to the border lines with Argentina and Bolivia and was occupied by different cultures in the past like Atacameos and lately by Incas in s. X V. About a century later Hispanic explorers visited the zone. The area is rich in tombs and remains. Due to the abundance of minerals, metallurgy was practiced by pre-Hispanic cultures. This work is part of a study concerning the characterization of metallic artifacts found in several excavations. The elemental composition can help in determining the provenance of the pieces, and the metallurgical techniques used. A set of twenty pieces including hatchets, knifes, chisels, maces and bells were analyzed by X ray fluorescence induced by photons of 59.5 keV provided by a source of Am-241. Detection of Mn, Fe, Ni, Cu, As, Zr, Ag, Sn, Sb, Ba, and Pb has allowed determination of their provenance. (Author)

  12. Electrical Bioimpedance-Controlled Surgical Instrumentation.

    Science.gov (United States)

    Brendle, Christian; Rein, Benjamin; Niesche, Annegret; Korff, Alexander; Radermacher, Klaus; Misgeld, Berno; Leonhardt, Steffen

    2015-10-01

    A bioimpedance-controlled concept for bone cement milling during revision total hip replacement is presented. Normally, the surgeon manually removes bone cement using a hammer and chisel. However, this procedure is relatively rough and unintended harm may occur to tissue at any time. The proposed bioimpedance-controlled surgical instrumentation improves this process because, for example, most risks associated with bone cement removal are avoided. The electrical bioimpedance measurements enable online process-control by using the milling head as both a cutting tool and measurement electrode at the same time. Furthermore, a novel integrated surgical milling tool is introduced, which allows acquisition of electrical bioimpedance data for online control; these data are used as a process variable. Process identification is based on finite element method simulation and on experimental studies with a rapid control prototyping system. The control loop design includes the identified process model, the characterization of noise as being normally distributed and the filtering, which is necessary for sufficient accuracy ( ±0.5 mm). Also, in a comparative study, noise suppression is investigated in silico with a moving average filter and a Kalman filter. Finally, performance analysis shows that the bioimpedance-controlled surgical instrumentation may also performs effectively at a higher feed rate (e.g., 5 mm/s). PMID:25423656

  13. Results from investigations with an instrumented impact machine on a molybdenum base alloy, nickel base alloys, and Incoloy 800

    International Nuclear Information System (INIS)

    Experiments were performed on the molybdenum base alloy TZM, the nickel base alloys Nimocast 713 LC, Inconel 625, Nimonic 86, Hastelloy S, and the iron base alloy Incoloy 800 with an instrumented impact machine. The results are discussed in terms of absorbed impact energies and dynamic fracture toughness. In all cases the agreement between the energy determined by the dial reading and the energy determined by the integration of the load vs. load point displacement diagram was excellent. A procedure for the determination of the dynamic fracture toughness for load vs. load point displacement diagrams exhibiting high oscillations using an averaged curve is proposed. Using this procedure a pronounced influence of the experiments with tup and chisel (5.0 m/s and 0.1 m/s respectively) on the dynamic fracture toughness is not detectable. Using half the drop height, i.e. halving the total energy, lowers the dynamic fracture toughness values for these types of alloys. Low absorbed impact energies are often combined with high fracture toughness values. In these cases there is no or only a small reserve in deformation and/or stable crack growth. (Auth.)

  14. Effects of 24 Years of Conservation Tillage Systems on Soil Organic Carbon and Soil Productivity

    Directory of Open Access Journals (Sweden)

    Kenneth R. Olson

    2013-01-01

    Full Text Available The 24-year study was conducted in southern Illinois (USA on land similar to that being removed from Conservation Reserve Program (CRP to evaluate the effects of conservation tillage systems on: (1 amount and rates of soil organic carbon (SOC storage and retention, (2 the long-term corn and soybean yields, and (3 maintenance and restoration of soil productivity of previously eroded soils. The no-till (NT plots did store and retain 7.8 Mg C ha−1 more and chisel plow (CP −1.6 Mg C ha−1 less SOC in the soil than moldboard plow (MP during the 24 years. However, no SOC sequestration occurred in the sloping and eroding NT, CP, and MP plots since the SOC level of the plot area was greater at the start of the experiment than at the end. The NT plots actually lost a total of −1.2 Mg C ha−1, the CP lost −9.9 Mg C ha−1, and the MP lost −8.2 Mg C ha−1 during the 24-year study. The long-term productivity of NT compared favorably with that of MP and CP systems.

  15. Effects of Reduced Tillage on Crop Yield, Plant Available Nutrients and Soil Organic Matter in a 12-Year Long-Term Trial under Organic Management

    Directory of Open Access Journals (Sweden)

    Wilhelm Claupein

    2013-09-01

    Full Text Available A field experiment was performed in Southwest Germany to examine the effects of long-term reduced tillage (2000–2012. Tillage treatments were deep moldboard plow: DP, 25 cm; double-layer plow; DLP, 15 + 10 cm, shallow moldboard plow: SP, 15 cm and chisel plow: CP, 15 cm, each of them with or without preceding stubble tillage. The mean yields of a typical eight-year crop rotation were 22% lower with CP compared to DP, and 3% lower with SP and DLP. Stubble tillage increased yields by 11% across all treatments. Soil nutrients were high with all tillage strategies and amounted for 34–57 mg kg−1 P and 48–113 mg kg−1 K (0–60 cm soil depth. Humus budgets showed a high carbon input via crops but this was not reflected in the actual Corg content of the soil. Corg decreased as soil depth increased from 13.7 g kg−1 (0–20 cm to 4.3 g kg−1 (40–60 cm across all treatments. After 12 years of experiment, SP and CP resulted in significantly higher Corg content in 0–20 cm soil depth, compared to DP and DLP. Stubble tillage had no significant effect on Corg. Stubble tillage combined with reduced primary tillage can sustain yield levels without compromising beneficial effects from reduced tillage on Corg and available nutrient content.

  16. Concrete decontamination and demolition methods

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE), Division of Environmental Control Technology, requested Nuclear Energy Services to prepare a handbook for the decontamination and decommissioning (D and D) of DOE-owned and commercially-owned radioactive facilities. the objective of the handbook is to provide the nuclear industry with guidance on the state-of-the-art methods and equipment available for decommissioning and to provide the means to estimate decommissioning costs and environmental impact. The methods available for concrete decontamination and demolition are summarized to provide an overview of some of the state-of-the-art techniques to be discussed at this workshop. The pertinent information on each method will include the selection factors such as the rate of performance in terms of concrete removal per unit time (cubic yards per day), manpower required by craft, unit cost (dollars per cubic yard) and the advantages and disadvantages. The methods included in this overview are those that have been routinely used in nuclear and nonnuclear applications or demonstrated in field tests. These methods include controlled blasting, wrecking ball or slab, backhoe mounted ram, flame torch, thermic lance, rock splitter, demolition compound, sawing, core stitch drilling, explosive cutting, paving breaker and power chisel, drill and spall, scarifying, water cannon and grinding

  17. The experience gained from the decommissioning of the Niederaichbach nuclear power plant

    International Nuclear Information System (INIS)

    The Niederaichbach nuclear power plant (KKN) is a former prototype equipped with a heavy water moderated and CO2 cooled 100 MWe reactor. It was shut down in 1974 after having generated the equivalent of 18 full load days due to technical problems associated with the stream generators, KKN was transferred to the stage of 'safe enclosure'. The decommissioning work began in July 1988 with the disassembling of inactive and later of contaminated components. At the end of November 1990 this project entered the most challenging phase, when the remote-controlled dismantling of the pressure tube reactor was started. The dismantling of the reactor as well as the segmentation of the thermal shield were completed in March 1993. The total mass of the reactor amounts to 522 tons with a radioactivity of 8.6 x 106 MBq. It is packaged in 139 containers to be disposed of in the Konrad repository. The containers are currently accommodated in the Forschungszentrum Karlsruhe intermediate storage building until Konrad will probably start its operation in 1995. The dismantling of the activated concrete structures inside the reactor containment was completed successfully in November 1993. For the removal of these areas and components either an electrically driven hydraulic excavator with a rock chisel or hydraulic and pyrotechnical explosion was applied. The decontamination and free release of the KKN facility from the Atomic Law started in November 1993 and was completed in August 1994. Finally the demolition of the remaining buildings is expected to be concluded in autumn 1995. (author)

  18. In-situ XRF and LIBS analysis of roman silver denarii

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, A. El; Harith, M.A. [National Institute for Laser- Enhanced Science (NILES), Cairo University, Giza (Egypt); Ferretti, M. [Istituto per le Tecnologie Applicate ai Beni Culturali, Area della Ricerca del CNR di Montelibretti, Roma (Italy); Foresta, A.; Legnaioli, S.; Lorenzetti, G.; Palleschi, V.; Pardini, L., E-mail: incenzo.palleschi@cnr.it [Istituto di Chimica dei Composti Organometallici del CNR. Area della Ricerca del CNR di Pisa (Italy); Nebbia, E. [Universita degli Studi di Torino (Italy); Catalli, F. [Monetiere di Firenze, Museo Archeologico Nazionale, Firenze (Italy)

    2011-07-01

    Full text: In this paper we present the result of a study performed on a large collection of silver roman republican denarii, encompassing about two centuries of history. The joint use of Laser-Induced Breakdown Spectroscopy (LIBS) and X-Ray Fluorescence (XRF) spectroscopy allowed for an accurate determination of the coins' elemental composition; the measurements, performed mostly in situ at the 'Monetiere' in Florence, revealed a striking correlation of the 'quality' of the silver alloy with some crucial contemporary events. This finding was used for classifying a group of denarii whose dating was otherwise impossible. The results reported demonstrate the possibility of analyzing in short time and in situ a statistically significant number of coins. Useful information can be obtained about the coin composition, both for main components and traces that could be used for classifying the coins in groups, according to different levels of concentrations of the detected elements. The comparison with other contemporary denarii allowed also to controvert a recent theory on the origin of the so called 'serrated' denarii (denarii showing notched chisel marks on the edge of the coin). (author)

  19. Rebeca Matte. El cuerpo de la histeria

    Directory of Open Access Journals (Sweden)

    Gloria Cortés Aliaga

    2015-12-01

    Full Text Available In 1876-77 Bourneville and Regnard published in France the album Iconographie Photographique de la Salpêtrière with studies of the psychiatrist Jean-Martin Charcot (1825-1893. The album gave account of the phases of hysteria in the most important psychiatric hospice of Paris and its images reproduced a series of postures that became an iconographical and theatrical source for a series of problematic female. Twenty-three years later, the chilean sculptress Rebeca Matte sent to the official Salon the work Horace (1899, characterized by physical and psychological rigidity that are associated with the hysterical-epileptic attacks seizures and to certain states of dementia framed in experiences of delirium, paralysis and abandonment of reason. From Horace Rebeca brings out its chisel a variety of figures and neighboring neurotic, phallic and histrionic that allow wonder on the reception of psychoanalysis and the study of hysteria in the female space. Could they be instruments of sublimation that allow experiencing the most widespread disorders of the female "madness”? Or rather tools of reporting on what psychoanalysis defined as a delimitation of "being a woman"?

  20. Influence of Tillage and Daily Manure Application on the Survival of Bacterial Pathogens Indicators in Soil and on Radish

    International Nuclear Information System (INIS)

    We measured Escherichia coli, and Enterococcus sp. numbers in soil and on fresh radish (Raphanus sativus L.) at 1, 7, 14, 28, 54, and 84 days after the addition of high and low amounts of solid dairy manure in combination with chisel tillage to a 20 cm depth (deep) or roller tillage to a 10 cm depth (shallow). When the high or low amount of solid dairy manure was added to the soil, E. coli populations in soil were higher in the 54 days following manure addition compared to the control treatment. Dairy manure addition increased Enterococcus sp. in soils compared to the control treatment for the entire 84 days sampling period. At harvest, which was 84 days after application, we did not detect E. coli in radish in rhizosphere soil or on radish roots. Addition of solid dairy manure increased Enterococcus sp. numbers in radish rhizosphere soil and on radish roots. We suggest that fresh animal manure be applied to soil at least 120 days prior to planting to allow die-off of human pathogenic bacteria and reduce the incidence of bacterial adhesion on or bacterial colonization of ready to eat vegetables.

  1. Transmaxillary Sinus Approach for Le Fort II Osteotomy.

    Science.gov (United States)

    Kobayashi, Shinji; Fukawa, Toshihiko; Hirakawa, Takashi; Satake, Toshihiko; Maegawa, Jiro

    2016-02-01

    The Le Fort II osteotomy is a relatively rare operation. The posterior wall osteotomy of the maxillary sinus (MS) is often difficult for Le Fort III. We developed the transmaxillary sinus approach (TSA) for the Le Fort II osteotomy that cuts the posterior wall of the MS directly. This report illustrates this easy-to-use procedure for the Le Fort II osteotomy in syndromic craniosynostosis. This procedure was performed in an 18-year-old patient with Apert syndrome and a 15-year-old patient with Pfeiffer syndrome. The thin anterior walls of the MS were removed through an intraoral approach to look inside the MS. Then, the posterior walls were cut by chisel under direct vision using light. The other osteotomy was performed as usual. Distraction osteogenesis with internal and external devices was used in combination. The advantages of TSA are the direct posterior wall osteotomy of the MS with no down fracture and minimal invasiveness to the mucosa of the MS under direct vision. However, the disadvantage is that TSA becomes a blind procedure in a case with no MS or hypoplasia. We developed the TSA for the Le Fort II osteotomy, which could provide direct observation and perform the posterior wall osteotomy of the MS without down fracture. We believe that TSA is an effective surgical procedure for the Le Fort II osteotomy. PMID:27014548

  2. Root-knot nematode management in double-cropped plasticulture vegetables.

    Science.gov (United States)

    Desaeger, J A; Csinos, A S

    2006-03-01

    Combination treatments of chisel-injected fumigants (methyl bromide, 1,3-D, metam sodium, and chloropicrin) on a first crop, followed by drip-applied fumigants (metam sodium and 1,3-D +/- chloropicrin) on a second crop, with and without oxamyl drip applications were evaluated for control of Meloidogyne incognita in three different tests (2002 to 2004) in Tifton, GA. First crops were eggplant or tomato, and second crops were cantaloupe, squash, or jalapeno pepper. Double-cropped vegetables suffered much greater root-knot nematode (RKN) pressure than first crops, and almost-total yield loss occurred when second crops received no nematicide treatment. On a first crop of eggplant, all fumigants provided good nematode control and average yield increases of 10% to 15 %. On second crops, higher application rates and fumigant combinations (metam sodium and 1,3-D +/- chloropicrin) improved RKN control and increased yields on average by 20% to 35 % compared to the nonfumigated control. Oxamyl increased yields of the first crop in 2003 on average by 10% to 15% but had no effect in 2004 when RKN failed to establish itself. On double-cropped squash in 2003, oxamyl following fumigation provided significant additional reduction in nematode infection and increased squash yields on average by 30% to 75%. PMID:19259431

  3. Radioecological estimation of biotops in the territory of Imishli region of Azerbaijan Republic

    International Nuclear Information System (INIS)

    Full text : The ecosystem level of structurisation of a live matter is the basic subject of ecological, in particular radio ecological science. Quality of biotopes - a complex of the lifeless nature on which all inhabitants of the given ecosystem live, is a basic condition of its existence. In the given work it was investigated the maintenance of natural and artificial radionuclides in an arable layer of soils, on the basis of the received data estimated quality of the biotopes located in territory of Imishli administrative area of Azerbaijan. Imishli is one of the areas of Republic most subject to strong anthropogenous loading. Along with agricultural, in area territory works on oil recovery are conducted that also can lead to pollution of soils with natural radionuclides, containing as a part of chisel waters (2235U, 2238U, 2232Th, 2226Ra, 2228Ra) and with oil. On the basis of the spent radiospectrometer analyses of the soil samples which have been selected from enough of the soil cuts, the radioecological situation on all area has been estimated and corresponding cards were made

  4. Designing an intelligent system to predict drill wear by using of motor current and fuzzy logic method - doi: 10.4025/actascitechnol.v35i4.15647

    Directory of Open Access Journals (Sweden)

    Aydin Salimi

    2013-10-01

    Full Text Available In automation flexible manufacturing systems, tool wear detection during the cutting process is one of the most important considerations. This study presents an intelligent system for online tool condition monitoring in drilling process. In this paper, analytical and empirical models have been used to predict the thrust and cutting forces on the lip and chisel edges of a new drill. Also an empirical model is used to estimate tool wear rate and force values on the edges of the worn drill .By using the block diagram of machine tool drives, the changes in the feed and spindle motor currents are simulated, as wear rate increases. To predict tool wear rate, fuzzy logic capabilities have been used to develop an intelligent system. The simulation results presented with MATLAB software show the effectiveness of proposed system for on-line drill wear monitoring. This is confirmed by comparing the measured and estimated values with each other in which the value of R2 was obtained 0.9367 in the regression graph.  

  5. Weed infestation in canopy of spring barley in condition of different tillage systems and fertilization and plant protection levels

    Directory of Open Access Journals (Sweden)

    Piotr Kraska

    2012-12-01

    Full Text Available The purpose of this work was to determine the influence of conventional tillage (fall ploughing at 25 cm and minimum tillage systems (chisel ploughing at 30 cm and two differentiated fertilization and plant protection levels on number, species composition and air dry weed mass in spring barley cv. Rataj. This spring barley was cultivated in crop rotation potato - spring barley - winter rye. The analysis of field infestation was made prior to spring barley harvest with quantitative- weighting method. There was estimated number of weeds, weed species composition and air dry weight of weeds in two randomly chosen areas of each plot of 0.5 m2. The density of weeds and weed air dry weight was statistically analysed by means of variance analysis, and the mean values were estimated with Tukey's confidence intervals (p=0.05. Intensive level of fertilization and chemical crop protection decreased number of monocotyledonous weeds and total weeds in canopy of spring barley. Conventional system of soil cultivation decreased in a canopy of spring barley the following species of weeds: Geranium pusillum, Galinsoga parviflora, Stellaria media, Apera spica-venti, Poa annua and Echinochloa crusgalli. Conventional tillage increases number of Chamomilla suaveolens and Fallopia convolvulus in a canopy of spring barley. Intensive fertilization and plant protection levels decreased weed infestation first of all through Echinochloa crusgalli, Apera spica-venti, Fallopia convolvulus, Galinsoga parviflora, Geranium pusillum, Chenopodium album and Setaria pumila.

  6. Morphology and topographic anatomy of the spinal cord of the red-footed tortoise (Geochelone carbonaria Spix, 1824

    Directory of Open Access Journals (Sweden)

    Rafael C Carvalho

    2011-12-01

    Full Text Available The aim of this study was to describe the topography of the spinal cord of the red-footed tortoise to establish a morphological basis for applied research in anesthesiology and morphology. Six tortoises from the state of Maranhão (Brazil that had died of natural causes were used. The common carotid artery was used to perfuse the arterial system with saline solution (heated to 37ºC and to fix the material with a 20% formaldehyde solution. The specimens were then placed in a modified decalcifying solution for 72 hours to allow dorsal opening of the carapace with a chisel and an orthopedic hammer. Dissection of the dorsal musculature and sectioning of the vertebral arches were performed to access the spinal cord. The results revealed the spinal cord of G. carbonaria to be an elongated, whitish mass that reached the articulation between the penultimate and last caudal vertebrae. The cervical intumescence (Intumescentia cervicalis was located between vertebral segments C5 and T1, whereas the lumbosacral intumescence (Intumescentia lumbalis was located between T6 and Ca1.

  7. Quantification of the macrofauna in a vertisol under different systems from handling in the Cauca Valley, Colombia

    International Nuclear Information System (INIS)

    Using the tropical soil biology and fertility (TSBF) methodology the biodiversity, the density and biomass of macrofauna was evaluated in a vertisol soil under four tillage systems and in a cocoa plantation with an undisturbed for more than 20 years. Soil under cocoa showed the highest values of biodiversity (47 u.t.) while mulch tiller treatment showed the highest density (122 ind. 0.062 m2) and direct seeding the highest value of biomass (5.44 g. 0.062 m2). Ants, Myriapods and earthworms exhibited greater level of population density (41 +/- 28; 15 +/- 8 and 8 +/- 5 ind. 0.062 m2, respectively) while the greatest contribution to biomass was made by earthworms and coleoptera population with 2.3 +/- 1.7 and 0.27 +/- 0.32 g. 0.062 m2. Soil under cocoa plantation and direct seeding presented the highest proportion of macrofauna at the top 5 cm (58.2 and 51.1 % respectively) while treatments with soil disturbance as mulch tiller, disk plowing and chisel plow the distribution of macrofauna was between 5 to 20 cm depth (55.8,53.7 and 46.2 %). this study evidenced the sensibility of the soil's macrofauna to different tillage systems. Macrofauna quantifying could be used to evaluate soil conditions under different management methods

  8. System DECON - an innovative solution for the decontamination of surfaces in buildings

    International Nuclear Information System (INIS)

    One of the most important tasks in decommissioning nuclear facilities is, in disposal-oriented dismantling, the removal of contaminated surfaces. These coatings are traditionally removed manually by chiseling, abrasive blasting or sanding. With these processes it is often the case that the dust particles are then released into the air and settle on surrounding surfaces (secondary contamination); the material lands on the floor. The time limits set by the Nuclear Energy Withdrawal Act increase the demand by the industry for a suitable system for decontamination work. Since the end of 2000 the tool-head DECON 300 is being used in connection with a powerful DECON vacuum system from HOCHTIEF for decontamination work. The initial experiences were gained in the pilot nuclear plant Kahl (VAK) and in the former fuel rods factory NUKEM-Alt, Hanau, and the performance specifications determined. The system was used for both the removal of concrete as well as for the removal of the decontamination coating, bricks and plaster. With the DECON system the entire range of contaminated surfaces on floors, masonries and ceilings can be handled ''in situ''. The efficiency of this mechanical removal process is proven by the total of the removal performance, the quality of the surface, the lack of dust and handling, while simultaneously meeting the requirements of the StrSchV (German Radiation Protection Ordinance). (orig.)

  9. X-Ray Fluorescence and Laser-Induced Breakdown Spectroscopy analysis of Roman silver denarii

    Energy Technology Data Exchange (ETDEWEB)

    Pardini, L. [Istituto di Chimica dei Composti Organometallici del CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); El Hassan, A. [National Institute for Laser- Enhanced Sciences (NILES), Cairo University Giza (Egypt); Ferretti, M. [Istituto per le Tecnologie Applicate ai Beni Culturali, Area della Ricerca del CNR di Montelibretti Roma (Italy); Foresta, A.; Legnaioli, S.; Lorenzetti, G. [Istituto di Chimica dei Composti Organometallici del CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Nebbia, E. [Universita degli Studi di Torino (Italy); Catalli, F. [Monetiere di Firenze, Museo Archeologico Nazionale Firenze (Italy); Harith, M.A. [National Institute for Laser- Enhanced Sciences (NILES), Cairo University Giza (Egypt); Diaz Pace, D. [Institute of Physics ' Arroyo Seco' , Faculty of Science, Tandil (Argentina); Anabitarte Garcia, F. [Photonics Engineering Group, University of Cantabria, Santander (Spain); Scuotto, M. [Dipartimento di Scienze Archeologiche, Via Galvani 1, 56126 Pisa (Italy); Palleschi, V., E-mail: vincenzo.palleschi@cnr.it [Istituto di Chimica dei Composti Organometallici del CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Dipartimento di Scienze Archeologiche, Via Galvani 1, 56126 Pisa (Italy)

    2012-08-15

    In this paper we present the results of a study performed on a large collection of silver Roman republican denarii, encompassing about two centuries of history. The joint use of Laser-Induced Breakdown Spectroscopy (LIBS) and X-Ray Fluorescence (XRF) spectroscopy allowed for an accurate determination of the coins' elemental composition; the measurements, performed mostly in situ at the 'Monetiere' in Florence, revealed a striking connection between the 'quality' of the silver alloy and some crucial contemporary events. This finding was used to classify a group of denarii whose dating was otherwise impossible. The comparison with other contemporary denarii disproves a recent theory on the origin of the so called 'serrated' denarii (denarii showing notched chisel marks on the edge of the coin). - Highlights: Black-Right-Pointing-Pointer We studied a large collection of Roman republican silver denarii. Black-Right-Pointing-Pointer XRF and LIBS allowed to determine the precious metal content of the coins. Black-Right-Pointing-Pointer A correlation of the 'quality' of the alloy with some contemporary events was found. Black-Right-Pointing-Pointer The study allowed to controvert a recent theory on the so called 'serrated' denarii.

  10. Soil and crop residue CO2-C emission under tillage systems in sugarcane-producing areas of southern Brazil

    Directory of Open Access Journals (Sweden)

    Luís Gustavo Teixeira

    2013-10-01

    Full Text Available Appropriate management of agricultural crop residues could result in increases on soil organic carbon (SOC and help to mitigate gas effect. To distinguish the contributions of SOC and sugarcane (Saccharum spp. residues to the short-term CO2-C loss, we studied the influence of several tillage systems: heavy offset disk harrow (HO, chisel plow (CP, rotary tiller (RT, and sugarcane mill tiller (SM in 2008, and CP, RT, SM, moldboard (MP, and subsoiler (SUB in 2009, with and without sugarcane residues relative to no-till (NT in the sugarcane producing region of Brazil. Soil CO2-C emissions were measured daily for two weeks after tillage using portable soil respiration systems. Daily CO2-C emissions declined after tillage regardless of tillage system. In 2008, total CO2-C from SOC and/or residue decomposition was greater for RT and lowest for CP. In 2009, emission was greatest for MP and CP with residues, and smallest for NT. SOC and residue contributed 47 % and 41 %, respectively, to total CO2-C emissions. Regarding the estimated emissions from sugarcane residue and SOC decomposition within the measurement period, CO2-C factor was similar to sugarcane residue and soil organic carbon decomposition, depending on the tillage system applied. Our approach may define new emission factors that are associated to tillage operations on bare or sugarcane-residue-covered soils to estimate the total carbon loss.

  11. Soil preparation and forage sowing time for crop-livestock integration in corn culture

    Directory of Open Access Journals (Sweden)

    Luiz Fernando de Andrade Fritsch

    2012-01-01

    Full Text Available This work was carried out during the 2008/2009 crop season, in an Oxisol. It was used a split-plot arrangement design, with each plot corresponding to a different soil preparation system and each split-plot corresponding to a different sowing time of the forage Brachiaria brizantha Stapf. The soil preparation systems were: heavy harrowing (HH, disk plough (DP, chisel plough (CP and no-till (NT, and the forage sowing times were: 0, 8, 16 and 25 days after sowing (DAS of corn, arranged in 16 treatments with 3 replicates. The productive and vegetative characteristics of the corn were evaluated. Soil preparations have influenced plant height and the first ear height, with the highest value found for the heavy harrow treatment. Forage sowing time had no influence on vegetative characteristics of the corn and productive characteristics were not influenced by the soil preparations. The forage sowing time had influence on corn productivity, causing decrease in competition with corn forage from 5 DAS. The productivity was highly correlated with the number of grains per ear.

  12. X-ray computed microtomography analysis of the influence of different agricultural treatments on the topsoil porosity of a Grey Brown Luvisol from Ontario

    Science.gov (United States)

    Taina, I. A.; Heck, R. J.; Scaiff, N. T.

    2009-05-01

    One of the most important applications of X-ray computed tomography (CT) for the study of soil is the characterization of the shape and spatial distribution of pores. Analysis of 3D X-ray CT image data, related to different pore categories, can provide insight to soil structural changes, which have implications in water infiltration and soil aeration, resulting from agricultural practices. The aim of this study was to evaluate changes in the spatial characteristics of voids, due to tillage practices, in the Ap horizon of an Orthic Grey- Brown Luvisol (located at the Elora Research Station of the University of Guelph). Undisturbed oriented soil samples were collected from ten plots representing different tillage treatments: spring moldboard plow, spring moldboard plow, cultivate and pack, fall moldboard plow, cultivate and pack, spring tandem disc, no cultivator, fall offset disc, fall offset disc, cultivate and pack, fall chisel plow, cultivate and pack, zero zone till (soys twin rows), zero tillage (long term), and zero tillage (corn residue removed in row, soys twin rows). Since the utilization of standardized classes, in the quantification of similar features, proved to be necessary in order to obtain comparable results, categories of pores, separated according to their size, circularity and orientation were considered in the interpretation of data. Total volume of pores and volume percentage of each class were calculated, revealing substantial differences among the analyzed soil samples.

  13. Fracture analysis of compression damage in glass fabric/epoxy, G-10CR, 295 K to 4 K

    International Nuclear Information System (INIS)

    This report describes scanning electron and optical microscope fractographic and modeling studies of G-10CR compression fracture at room and cryogenic temperatures. Results of the fractography have shown that the failure events included three kinds of primary fracture patterns which, to varying degrees, are temperature-related. These fractures have been identified as: (1) a 550 slant mode; (2) a chisel or V-notch mode; and (3) a complex or mixed mode. The influence of constituent properties and behavior have been integral considerations in assessing the fracture mechanism and in analytical interpretations of the fracture behavior. As in other materials, the damage zone in these composites is the result of either discrete or interactive constituent failure processes (or both) occurring in a highly strained region of the specimen. Fiber microcracking or fracture, matrix yielding or cracking, and interface failure are examples of such events. Nucleation and propagation of fracture, as in other fiber-reinforced composites, is a function of microstructure, microdeformation, and the structural interaction of the constituents. Compressive strength data variability has been graphically correlated with primary and secondary fracture characteristics in order to understand the low temperature effects better

  14. The production of permanent plastic scales-I: photo-impregnation of complicated and precise scale pattern on 'PERSPEX'

    Directory of Open Access Journals (Sweden)

    P.K. Ray Chaudhuri

    1959-10-01

    Full Text Available This paper deals with the production of 'Perspex' protractors where the image pattern becomes integral with the base by a process based on photo-impregnation principle. This process involves building up of an impervious photographic stencil in a resistant material usually termed a 'Resist' (a coating that protects the area it covers from chemical action on the "perspex" surface followed by chemical attack on the exposed portions of the plastic through the unmasked areas of the stencil with a tinted solution of an adequate solvent preparation. The image is rendered visible by the combined softening, penetrating and staining effects initiated by the etching cum dyeing mordant on the base. In course of the treatment the dye gets entrapped and deeply embedded into the material of the base. The tender dyed characters are allowed to harden and set by the evaporation of the solvents. The composition and action of the dye incorporating medium is so governed that it does not chisel by forming image wise cavities due to removal of material from the "perspex" as is usually associated with all commercial photo-mechanical etching processes.

  15. Design and scale-up of a semi-industrial downer-reactor for the rounding of irregular polymer particles

    Science.gov (United States)

    Sachs, Marius; Schmidt, Jochen; Peukert, Wolfgang; Wirth, Karl-Ernst

    2016-03-01

    The recent development of rapid prototyping technologies towards additive manufacturing reveals some major drawbacks of processes such as laser beam melting (LBM). This contribution focuses on the lack of suitable polymer material with a fine particle size and good flowability. Polymer particles obtained by a wet grinding process 1 are treated in a heated downer reactor. This treatment changes the particles' morphology from a chiselled state towards a spherical form by surface tension forces in a molten state 2 and leads to an improved flowability. To reach the required amount of rounded polymer powder, a downer reactor in semi-industrial scale has been established and will be characterized in this article. For the purpose of particle rounding it is necessary to avoid contact of molten particles with each other and with the hot reactor walls. Furthermore, the heat distribution has been investigated as one of the key parameters of the process. Finally, a proof of concept by rounding wet grinded PBT material was successfully conducted. The product was examined to obtain data about a change in particle size and flowability.

  16. Effects of Tillage Management Systems on Residue Cover and Decomposition

    Institute of Scientific and Technical Information of China (English)

    ZHANGZHIGUO; XUQI; 等

    1998-01-01

    The effects of tillage methods on percent surface residue cover remaining and decomposition rates of crop residues were evaluated in this study.The line transect method was used to measure residue cover percentage on continuumous corn(Zea mays L.) plots under no tillage (NT),Conventional tillage(CT),chisel plow(CH),and disk tillage (DT).Samples of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) were used for residue decompostion study,Results showed that the percentage of residue cover remaining was significantly higher for NT than for CH and DT and that for CT was the lowest(<10%),For the same tillage system ,the percent residue cover remaining was significantly higher in the higher fertilizer N rate treatments relative to the lower fertilizer N treatments.weight losses of rye and vetch residues followed a similar pattern under CT and DT ,and they were significantly faster in CT and DT than in NT system ,Alo ,the amounts of residue N remaining during the first 16 weeks were alway higher under NT than under CT and DT.

  17. Assessment the effects of different tillage methods on chickpea yield and some yield components

    Directory of Open Access Journals (Sweden)

    Abdullah KASAP

    2013-06-01

    Full Text Available This study was carried out to determine the effects of different soil tillage methods on crop yield and some yield components in chickpea cultivation. For this reason, experimental trials were performed in Çayköy and Güzelpınar in Tokat-Kazova during 2008, 2009 and 2010. In this trials Gökçe cultivar of chickpea was used. Six different soil tillage methods were applied which were, mouldboard plough tillage in fall + cultivator in the spring + tooth harrow (Method A, mouldboard plough tillage in spring + cultivator + tooth harrow (Method B, rotary tiller in the spring (Method C, chisel in the spring + disc harrow and slider (Method D, strip tillage with router rotary hoe (Method E and direct seeding (Method F. Trials were set up in completely randomized block design with three replications. The results indicated that the highest average plant and seed yield per square meter was obtained with method A (470.74 g and 260.63 g and followed by method B (459.43 g and 254.18 g and method D (447.82 g and 247.23 g. In terms of factors evaluated; A, B and D methods were superior compared to the other methods.

  18. Geostatistical analysis of microrelief of an oxisol as a function of tillage and cumulative rainfall Análise geoestatística do microrrelevo de um Latossolo em função do preparo do solo e da precipitação acumulada

    Directory of Open Access Journals (Sweden)

    Eva Vidal Vázquez

    2009-04-01

    Full Text Available Surface roughness can be influenced by type and intensity of soil tillage among other factors. In tilled soils microrelief may decay considerably as rain progresses. Geostatistics provides some tools that may be useful to study the dynamics of soil surface variability. The objective of this study was to show how it is possible to apply geostatistics to analyze soil microrelief variability. Data were taken at an Oxisol over six tillage treatments, namely, disk harrow, disk plow, chisel plow, disk harrow + disk level, disk plow + disk level and chisel plow + disk level. Measurements were made initially just after tillage and subsequently after cumulative natural rainfall events. Duplicated measurements were taken in each one of the treatments and dates of samplings, yielding a total of 48 experimental surfaces. A pin microrelief meter was used for the surface roughness measurements. The plot area was 1.35 × 1.35 m and the sample spacing was 25 mm, yielding a total of 3,025 data points per measurement. Before geostatistical analysis, trend was removed from the experimental data by two methods for comparison. Models were fitted to the semivariograms of each surface and the model parameters were analyzed. The trend removing method affected the geostatistical results. The geostatistical parameter dependence ratio showed that spatial dependence improved for most of the surfaces as the amount of cumulative rainfall increased.A rugosidade da superfície pode ser influenciada pelo tipo e pela intensidade do preparo do solo, entre outros fatores. Em solos preparados o microrrelevo é aplanado consideravelmente com o acúmulo da chuva. A Geoestatística promove algumas ferramentas que podem ser úteis no estudo da dinâmica da variabilidade da superfície do solo. O objetivo desse estudo foi verificar se é possível aplicar geoestatística na análise da variação do microrrelevo do solo. Os resultados foram obtidos num Latossolo sob seis tratamentos de

  19. A multifractal approach to characterize cumulative rainfall and tillage effects on soil surface micro-topography and to predict depression storage

    Directory of Open Access Journals (Sweden)

    E. Vidal Vázquez

    2010-03-01

    Full Text Available Most of the indices currently employed for assessing soil surface micro-topography, such as random roughness (RR, are merely descriptors of its vertical component. Recently, multifractal analysis provided a new insight for describing the spatial configuration of soil surface roughness. The main objective of this study was to test the ability of multifractal parameters to assess decay of initial surface roughness induced by natural rainfall under different soil tillage systems in field conditions. In addition, we evaluated the potential of the joint use of multifractal indices plus RR to improve predictions of water storage in depressions of the soil surface (MDS. Field experiments were performed on an Oxisol at Campinas, São Paulo State (Brazil. Six tillage treatments, namely, disc harrow, disc plough, chisel plough, disc harrow + disc level, disc plough + disc level and chisel plough + disc level were tested. In each treatment soil surface micro-topography was measured four times, with increasing amounts of natural rainfall, using a pin meter. The sampling scheme was a square grid with 25×25 mm point spacing and the plot size was 1350×1350 mm (≈1.8 m2, so that each data set consisted of 3025 individual elevation points. Duplicated measurements were taken per treatment and date, yielding a total of 48 experimental data sets. MDS was estimated from grid elevation data with a depression-filling algorithm. Multifractal analysis was performed for experimental data sets as well as for oriented and random surface conditions obtained from the former by removing slope and slope plus tillage marks, respectively. All the investigated microplots exhibited multifractal behaviour, irrespective of surface condition, but the degree of multifractality showed wide differences between them. Multifractal parameters provided valuable information for characterizing the spatial features of soil micro-topography as they were able to discriminate data

  20. A multifractal approach to characterize cumulative rainfall and tillage effects on soil surface micro-topography and to predict depression storage

    Directory of Open Access Journals (Sweden)

    E. Vidal Vázquez

    2010-10-01

    Full Text Available Most of the indices currently employed for assessing soil surface micro-topography, such as random roughness (RR, are merely descriptors of its vertical component. Recently, multifractal analysis provided a new insight for describing the spatial configuration of soil surface roughness. The main objective of this study was to test the ability of multifractal parameters to assess in field conditions the decay of initial surface roughness induced by natural rainfall under different soil tillage systems. In addition, we evaluated the potential of the joint use of multifractal indices plus RR to improve predictions of water storage in depressions of the soil surface (MDS. Field experiments were performed on an Oxisol at Campinas, São Paulo State (Brazil. Six tillage treatments, namely, disc harrow, disc plough, chisel plough, disc harrow + disc level, disc plough + disc level and chisel plough + disc level were tested. In each treatment soil surface micro-topography was measured four times, with increasing amounts of natural rainfall, using a pin meter. The sampling scheme was a square grid with 25 × 25 mm point spacing and the plot size was 1350 × 1350 mm (≈1.8 m2, so that each data set consisted of 3025 individual elevation points. Duplicated measurements were taken per treatment and date, yielding a total of 48 experimental data sets. MDS was estimated from grid elevation data with a depression-filling algorithm. Multifractal analysis was performed for experimental data sets as well as for oriented and random surface conditions obtained from the former by removing slope and slope plus tillage marks, respectively. All the investigated microplots exhibited multifractal behaviour, irrespective of surface condition, but the degree of multifractality showed wide differences between them. Multifractal parameters provided valuable information for characterizing the spatial features of soil micro-topography as they were able to

  1. Tillage and residue burning affects weed populations and seed banks.

    Science.gov (United States)

    Narwal, S; Sindel, B M; Jessop, R S

    2006-01-01

    An integrated weed management approach requires alternative management practices to herbicide use such as tillage, crop rotations and cultural controls to reduce soil weed seed banks. The objective of this study was to examine the value of different tillage practices and stubble burning to exhaust the seed bank of common weeds from the northern grain region of Australia. Five tillage and burning treatments were incorporated in a field experiment, at Armidale (30 degrees 30'S, 151 degrees 40'E), New South Wales, Australia in July 2004 in a randomized block design replicated four times. The trial was continued and treatments repeated in July 2005 with all the mature plants from the first year being allowed to shed seed in their respective treatment plots. The treatments were (i) no tillage (NT), (ii) chisel ploughing (CP), (iii) mould board ploughing (MBP), (iv) wheat straw burning with no tillage (SBNT) and (v) wheat straw burning with chisel ploughing (SBC). Soil samples were collected before applying treatments and before the weeds flowered to establish the seed bank status of the various weeds in the soil. Wheat was sown after the tillage treatments. Burning treatments were only initiated in the second year, one month prior to tillage treatments. The major weeds present in the seed bank before initiating the trial were Polygonum aviculare, Sonchus oleraceus and Avena fatua. Tillage promoted the germination of other weeds like Hibiscus trionum, Medicago sativa, Vicia sp. and Phalaris paradoxa later in the season in 2004 and Convolvulus erubescens emerged as a new weed in 2005. The MBP treatment in 2004 reduced the weed biomass to a significantly lower level of 55 g/m2 than the other treatments of CP (118 g/m2) and NT plots (196 g/m2) (P < 0.05). However, in 2005 SBC and MBP treatments were similar in reducing the weed biomass. In 2004, the grain yield trend of wheat was significantly different between CP and NT, and MBP and NT (P < 0.05) with maximum yield of 5898

  2. Water Erosion in Relation with Soil Management System and Crop Sequence during 20 Years on an Inceptisol in South Brazil

    Science.gov (United States)

    Bertol, I.; Schick, J.; Barbosa, F. T.; Paz-Ferreiro, J.; Flores, M. T.; Paz González, A.

    2012-04-01

    Soil erosion still remains persistent at the world scale, even if big efforts have been done to control and reduce it, mainly using soil crop residues to protect soil surface. Although in South Brazil the main management system for most crops is no tillage and direct drilling, water erosion prevails as the most important soil erosion type, which is due both, to the high erosivity and the evenly distribution of rainfall over the year. Moreover, some crops are still grown under soil tillage systems consisting of ploughing, harrowing and less frequently chiselling. Starting 1992, a field experiment under natural rainfall has been conducted on an Inceptisol located in Lages, Santa Catarina State, Brazil, which objective was to assess rainfall water erosion. Two soil cover conditions and four soil management systems were studied: I) a crop rotation, which included oats (Avena strigosa), soybean (Glycine max), common vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and common bean (Phaseolus vulgaris) under the following soil management types: 1) ploughing plus two levelling operations (CT), chiselling plus levelling (RT) and direct drilling with no tillage (NT), and II) bare soil (BS) without crop cover tilled by ploughing plus two levelling. In more than 90% of the study cases, soil losses were collected for single rain events with erosive power, whose erosivity was calculated. Total rain recorded during the 20 year experimental period was approximately 66,400 mm, which is equivalent to roughly 105,700, MJ mm ha-1 h-1 (EI30), whereas soil losses in the BS treatment were higher than 1,700 t.ha-1. On average, soil losses under RT treatment showed a 92% reduction in relation with BS, whereas under CT the reduction in relation to BS was about 66%. Soil management by direct drilling (NT) was the most efficient system to minimize water erosion, as soil losses decreased about 98% when compared with BS. Moreover, soil management systems with a crop

  3. Determination of paleoseismic activity over a large time-scale: Fault scarp dating with 36Cl

    Science.gov (United States)

    Mozafari Amiri, Nasim; Tikhomirov, Dmitry; Sümer, Ökmen; Özkaymak, Çaǧlar; Uzel, Bora; Ivy-Ochs, Susan; Vockenhuber, Christof; Sözbilir, Hasan; Akçar, Naki

    2016-04-01

    Bedrock fault scarps are the most direct evidence of past earthquakes to reconstruct seismic activity in a large time-scale using cosmogenic 36Cl dating if built in carbonates. For this method, a surface along the fault scarp with a minimum amount of erosion is required to be chosen as an ideal target point. The section of the fault selected for sampling should cover at least two meters of the fault surface from the lower part of the scarp, where intersects with colluvium wedge. Ideally, sampling should be performed on a continuous strip along the direction of the fault slip direction. First, samples of 10 cm high and 15 cm wide are marked on the fault surface. Then, they are collected using cutters, hammer and chisel in a thickness of 3 cm. The main geometrical factors of scarp dip, scarp height, top surface dip and colluvium dip are also measured. Topographic shielding in the sampling spot is important to be estimated as well. Moreover, density of the fault scarp and colluvium are calculated. The physical and chemical preparations are carried in laboratory for AMS and chemical analysis of the samples. A Matlab® code is used for modelling of seismically active periods based on increasing production rate of 36Cl following each rupture, when a buried section of a fault is exposed. Therefore, by measuring the amount of cosmogenic 36Cl versus height, the timing of major ruptures and their offsets are determined. In our study, Manastır, Mugırtepe and Rahmiye faults in Gediz graben, Priene-Sazlı, Kalafat and Yavansu faults in Büyük Menderes graben and Ören fault in Gökava half-graben have been examined in the seismically active region of Western Turkey. Our results reconstruct at least five periods of high seismic activity during the Holocene time, three of which reveal seismic ruptures beyond the historical pre-existing data.

  4. Influence of prior thermal ageing on tensile deformation and fracture behaviour of forged thick section 9Cr-1Mo ferritic steel

    International Nuclear Information System (INIS)

    Tensile tests were performed on specimens in quenched and tempered (Q + T) and thermally aged (TA) conditions over a wide temperature range (300-873 K) to assess the influence of prior thermal ageing on tensile deformation and fracture behaviour of forged thick section 9Cr-1Mo ferritic steel. Prior thermal ageing at 793 and 873 K for durations ranging from 10 to 5000 h did not cause a significant change in room temperature tensile properties. However, a marginal decrease in yield strength and reduction in area were observed for specimens aged for longer durations at 793 and 873 K. Prior thermal ageing at 793 K for 5000 h and at 873 K for 1000 and 5000 h produced significant reduction in strength values at intermediate temperatures (523-723 K) compared to that observed at high temperatures. At intermediate temperatures, the alloy in all heat treatment conditions exhibited serrated flow, a manifestation of dynamic strain ageing (DSA). The significant loss of strength in thermally aged conditions at intermediate temperatures has been attributed to reduced propensity to DSA. The elongation to fracture values at temperatures in the range 300-873 K were affected little by prior thermal ageing, whereas the reduction in area exhibited a decrease in the value with increasing thermal ageing. The fracture mode remained transgranular ductile at all test conditions investigated in the present study. However, specimens aged for longer durations exhibited chisel fracture at room and intermediate temperatures due to split in the martensite lath boundaries. The influence of thermal ageing on room temperature tensile properties of the forging remained similar to that reported for thin section 9Cr-1Mo steel. (orig.)

  5. Subsurface application of manures slurries for conservation tillage and pasture soils and their impact on the nitrogen balance.

    Science.gov (United States)

    Dell, Curtis J; Meisinger, John J; Beegle, Douglas B

    2011-01-01

    Injection of cattle and swine slurries can provide soil incorporation in no-till and perennial forage production. Injection is expected to substantially reduce N loss due to ammonia (NH3) volatilization, but a portion of that N conservation may be offset by greater denitrification and leaching losses. This paper reviews our current knowledge of the impacts of subsurface application of cattle and swine slurries on the N balance and outlines areas where a greater understanding is needed. Several publications have shown that liquid manure injection using disk openers, chisels, or tines can be expected to Sreduce NH, emissions by at least 40%, and often by 90% or more, relative to broadcast application. However, the limited number of studies that have also measured denitrification losses have shown that increased denitrification with subsurface application can offset as much as half of the N conserved by reducing NH3 emissions. Because the greenhouse gas nitrous oxide (N2O) is one product of denitrification, the possible increases in N2O emission with injection require further consideration. Subsurface manure application generally does not appear to increase leaching potential when manure is applied at recommended rates. Plant utilization of conserved N was shown in only a portion of the published studies, indicating that further work is needed to better synchronize manure N availability and crop uptake. At this time in the United States, the economic and environmental benefits from reducing losses of N as NH3 are expected to outweigh potential liability from increases in denitrification with subsurface manure application. To fully evaluate the trade-offs among manure application methods, a detailed environmental and agricultural economic assessment is needed to estimate the true costs of potential increases in NO2O emissions with manure injection. PMID:21520742

  6. The current status and future prospects of computer-assisted hip surgery.

    Science.gov (United States)

    Inaba, Yutaka; Kobayashi, Naomi; Ike, Hiroyuki; Kubota, So; Saito, Tomoyuki

    2016-03-01

    The advances in computer assistance technology have allowed detailed three-dimensional preoperative planning and simulation of preoperative plans. The use of a navigation system as an intraoperative assistance tool allows more accurate execution of the preoperative plan, compared to manual operation without assistance of the navigation system. In total hip arthroplasty using CT-based navigation, three-dimensional preoperative planning with computer software allows the surgeon to determine the optimal angle of implant placement at which implant impingement is unlikely to occur in the range of hip joint motion necessary for daily activities of living, and to determine the amount of three-dimensional correction for leg length and offset. With the use of computer navigation for intraoperative assistance, the preoperative plan can be precisely executed. In hip osteotomy using CT-based navigation, the navigation allows three-dimensional preoperative planning, intraoperative confirmation of osteotomy sites, safe performance of osteotomy even under poor visual conditions, and a reduction in exposure doses from intraoperative fluoroscopy. Positions of the tips of chisels can be displayed on the computer monitor during surgery in real time, and staff other than the operator can also be aware of the progress of surgery. Thus, computer navigation also has an educational value. On the other hand, its limitations include the need for placement of trackers, increased radiation exposure from preoperative CT scans, and prolonged operative time. Moreover, because the position of a bone fragment cannot be traced after osteotomy, methods to find its precise position after its movement need to be developed. Despite the need to develop methods for the postoperative evaluation of accuracy for osteotomy, further application and development of these systems are expected in the future. PMID:26850921

  7. Resistência à penetração e rendimento da soja após intervenção mecânica em latossolo vermelho sob plantio direto Penetration resistance and soybean yield after mechanical intervention on an oxisol under tillage

    Directory of Open Access Journals (Sweden)

    Marta Sandra Drescher

    2012-12-01

    íveis alocados na subparcela foram constituídos pela ação de uma semeadora de plantio direto equipada com discos duplos defasados atuando até 7 cm de profundidade e de uma semeadora equipada com discos duplos + haste atuando até 13 cm de profundidade. Os resultados obtidos indicaram que a intervenção mecânica em solo manejado sob SPD consolidado, mediante a prática de escarificação ou aração do solo, apresenta potencial efêmero para mitigar a compactação e promover a melhoria da estrutura do solo, com efeito residual de até dois anos e meio para a resistência do solo à penetração. A utilização de semeadora de plantio direto equipada com sulcador tipo haste + disco apresentou potencial para mitigação da compactação do solo, promovendo a redução da resistência mecânica do solo à penetração na camada de 7 - 15 cm de profundidade. Contudo, o efeito residual da intervenção mecânica para descompactação do solo e a adoção dos diferentes dispositivos de aplicação do adubo no sulco de semeadura não foram eficientes em alterar o rendimento de grãos da cultura da soja na safra agrícola 2008/2009.Compaction negatively affects a number of soil properties, e.g., resistance to root penetration and water and nutrient availability to plants, restricting the photosynthetic rate, shoot growth and consequently, the yield. When soil compaction becomes limiting to crop development, mitigation measures must be adopted. The purpose of this study was to evaluate the residual effect of mechanical soil plowing and chiseling, by a seeder with soil breakers (disks and disks plus short ripper as mitigation practice of the soil compaction under no-tillage (NT, on soil penetration resistance and soybean yield. In 2001, a study was conducted in Coxilha, in northern Rio Grande do Sul, on an Oxisol, in an area with a sequence of NT management. In this field, every year a treatment of mechanical soil decompression was applied, consisting of plowing and chiseling the

  8. Identification of Gene Modules Associated with Low Temperatures Response in Bambara Groundnut by Network-Based Analysis.

    Directory of Open Access Journals (Sweden)

    Venkata Suresh Bonthala

    Full Text Available Bambara groundnut (Vigna subterranea (L. Verdc. is an African legume and is a promising underutilized crop with good seed nutritional values. Low temperature stress in a number of African countries at night, such as Botswana, can effect the growth and development of bambara groundnut, leading to losses in potential crop yield. Therefore, in this study we developed a computational pipeline to identify and analyze the genes and gene modules associated with low temperature stress responses in bambara groundnut using the cross-species microarray technique (as bambara groundnut has no microarray chip coupled with network-based analysis. Analyses of the bambara groundnut transcriptome using cross-species gene expression data resulted in the identification of 375 and 659 differentially expressed genes (p<0.01 under the sub-optimal (23°C and very sub-optimal (18°C temperatures, respectively, of which 110 genes are commonly shared between the two stress conditions. The construction of a Highest Reciprocal Rank-based gene co-expression network, followed by its partition using a Heuristic Cluster Chiseling Algorithm resulted in 6 and 7 gene modules in sub-optimal and very sub-optimal temperature stresses being identified, respectively. Modules of sub-optimal temperature stress are principally enriched with carbohydrate and lipid metabolic processes, while most of the modules of very sub-optimal temperature stress are significantly enriched with responses to stimuli and various metabolic processes. Several transcription factors (from MYB, NAC, WRKY, WHIRLY & GATA classes that may regulate the downstream genes involved in response to stimulus in order for the plant to withstand very sub-optimal temperature stress were highlighted. The identified gene modules could be useful in breeding for low-temperature stress tolerant bambara groundnut varieties.

  9. Optimization of conventional X-ray images for the detection of hook of hamate fractures; Optimierung von konventionellen Roentgenaufnahmen zur Erkennung von Hamulus ossis hamati Frakturen

    Energy Technology Data Exchange (ETDEWEB)

    Andresen, R.; Adam, C. [Abt. fuer Bildgebende Diagnostik und Interventionelle Radiologie, KMG Klinikum Guestrow, Akademisches Lehrkrankenhaus der Univ. Rostock, Guestrow (Germany); Radmer, S. [Abt. fuer Orthopaedie und Rheumachirurgie, Immanuel Krankenhaus, Akademisches Lehrkrankenhaus der FU-Berlin (Germany); Scheufler, O. [Abt. fuer Plastische, Rekonstruktive und Aesthetische Chirurgie, Universitaetsspital Basel (Switzerland); Bogusch, G. [Inst. fuer Anatomie des Universitaetsklinikums Charite, Humboldt Univ. zu Berlin (Germany)

    2006-07-01

    Fractures of the hook of the hamate are a rare event. The fracture cannot always be detected clinically and standard radiographs do not always provide an overlap-free image of the hook of the hamate, so that fractures can easily be overlooked. The objective of the present study was to examine if the sensitivity of detecting hamulus ossis hamati fractures can further be improved by a modified conventional radiographic projection. After dissection of the hook of the hamate on 10 cadaver hands, a fracture was produced close to the base using a surgical chisel. Conventional radiographs were then performed in four different projections (dorso-palmar, lateral, carpal-tunnel and oblique view). The oblique view was obtained in a 45 supination position, slight extension and radial duction, with the tube tilted from distal to proximal by 30 . An axial spiral CT was used as a reference for detection of the fracture. The highest sensitivity of the conventional radiographs, with 8/10 identified fractures (80%), was achieved by the oblique view. The carpal-tunnel view with 4/10 (40%) and the dorso-palmar projection with 3/10 (30%) were much lower. All fractures were missed in the lateral projection. If all of the conventional radiographic projections are taken into account, the sensitivity is increased to 90%. All of the fractures were reliably detected in the axial CT-image. If a hamulus ossis hamati fracture is suspected clinically, in addition to the dorso-palmar and carpal-tunnel view, the special oblique view described here should be performed as a third projection plane, while the lateral view can be dispensed with. However, even if all projections are taken into account, a negative finding in the conventional radiographic imaging does not exclude a fracture with absolute certainty. In such cases, a CT or MRI should be performed to exclude a fracture. (orig.)

  10. Shear bond strength of orthodontic brackets after acid-etched and erbium-doped yttrium aluminum garnet laser-etched

    Science.gov (United States)

    Alavi, Shiva; Birang, Reza; Hajizadeh, Fatemeh

    2014-01-01

    Background: Laser ablation has been suggested as an alternative method to acid etching; however, previous studies have obtained contrasting results. The purpose of this study was to compare the shear bond strength (SBS) and fracture mode of orthodontic brackets that are bonded to enamel etched with acid and erbium-doped yttrium aluminum garnet (Er:YAG) laser. Materials and Methods: In this experimental in vitro study, buccal surfaces of 15 non-carious human premolars were divided into mesial and distal regions. Randomly, one of the regions was etched with 37% phosphoric acid for 15 s and another region irradiated with Er:YAG laser at 100 mJ energy and 20 Hz frequency for 20 s. Stainless steel brackets were then bonded using Transbond XT, following which all the samples were stored in distilled water for 24 h and then subjected to 500 thermal cycles. SBS was tested by a chisel edge, mounted on the crosshead of universal testing machine. After debonding, the teeth were examined under ×10 magnification and adhesive remnant index (ARI) score determined. SBS and ARI scores of the two groups were then compared using t-test and Mann-Whitney U test. Significant level was set at P < 0.05. Results: The mean SBS of the laser group (16.61 ± 7.7 MPa) was not significantly different from that of the acid-etched group (18.86 ± 6.09 MPa) (P = 0.41). There was no significant difference in the ARI scores between two groups (P = 0.08). However, in the laser group, more adhesive remained on the brackets, which is not suitable for orthodontic purposes. Conclusion: Laser etching at 100 mJ energy produced bond strength similar to acid etching. Therefore, Er:YAG laser may be an alternative method for conventional acid-etching. PMID:25097641

  11. Effect of restoration size on fracture resistance of bonded amalgam restorations.

    Science.gov (United States)

    Lindemuth, J S; Hagge, M S; Broome, J S

    2000-01-01

    The purpose of this study was to determine the effect of restoration size on the fracture strength of amalgam restorations bonded with Amalgambond Plus (with HPA). Research has shown that this adhesive is dispersed throughout the unset amalgam during condensation and that a decrease in diametral tensile strength, proportional to the amount of adhesive incorporated into the unset amalgam, has resulted. Smaller cavity preparations have a higher ratio of surface area to volume than do larger preparations, and it was anticipated that a proportionately greater amount of adhesive would be incorporated into smaller amalgam restorations. Sixty extracted human molars were divided into four groups of 15 teeth and mounted in tray acrylic-filled PVC cylinders. Shallow approximo-occlusal channels were prepared in two groups. One group was restored with Amalgambond Plus and Tytin amalgam, the other with just Tytin amalgam. Larger proximo-occlusal preparations were made in the remaining two groups, then restored in the same fashion. Samples were stored in 37 degrees C for at least 24 hours, then thermocycled from 5-55 degrees C 1000 times with a one-minute dwell time. Specimens were mounted in a Universal Testing Machine, and a chisel was applied to the restorations in compression mode at a crosshead speed of 5.0 mm/minute until bulk fracture of the amalgam occurred. The results indicated no difference in bulk fracture strengths between large amalgam restorations restored with and without Amalgambond Plus. However, small amalgam restorations restored with Amalgambond Plus exhibited significantly greater (p < 0.025) bulk fracture strengths than small amalgam restorations restored without use of the adhesive. PMID:11203813

  12. Comparison of Surface Water Quality and Yields from Organically and Conventionally Produced Sweet Corn Plots with Conservation and Conventional Tillage.

    Science.gov (United States)

    Edgell, Joshua; Osmond, D L; Line, D E; Hoyt, G D; Grossman, J M; Larsen, E M

    2015-11-01

    Organic agricultural systems are often assumed to be more sustainable than conventional farming, yet there has been little work comparing surface water quality from organic and conventional production, especially under the same cropping sequence. Our objective was to compare nutrient and sediment losses, as well as sweet corn ( L. var. ) yield, from organic and conventional production with conventional and conservation tillage. The experiment was located in the Appalachian Mountains of North Carolina. Four treatments, replicated four times, had been in place for over 18 yr and consisted of conventional tillage (chisel plow and disk) with conventional production (CT/Conven), conservation no-till with conventional production (NT/Conven), conventional tillage with organic production (CT/Org), and conservation no-till with organic production (NT/Org). Water quality (surface flow volume; nitrogen, phosphorus, and sediment concentrations) and sweet corn yield data were collected in 2011 and 2012. Sediment and sediment-attached nutrient losses were influenced by tillage and cropping system in 2011, due to higher rainfall, and tillage in 2012. Soluble nutrients were affected by the nutrient source and rate, which are a function of the cropping system. Sweet corn marketable yields were greater in conventional systems due to high weed competition and reduced total nitrogen availability in organic treatments. When comparing treatment efficiency (yield kg ha /nutrient loss kg ha ), the NT/Conven treatment had the greatest sweet corn yield per unit of nutrient and sediment loss. Other treatment ratios were similar to each other; thus, it appears the most sustainably productive treatment was NT/Conven. PMID:26641338

  13. EFFECT OF SOIL TILLAGE AND PLANT RESIDUE ON SURFACE ROUGHNESS OF AN OXISOL UNDER SIMULATED RAIN

    Directory of Open Access Journals (Sweden)

    Elói Panachuki

    2015-02-01

    Full Text Available Surface roughness of the soil is formed by mechanical tillage and is also influenced by the kind and amount of plant residue, among other factors. Its persistence over time mainly depends on the fundamental characteristics of rain and soil type. However, few studies have been developed to evaluate these factors in Latossolos (Oxisols. In this study, we evaluated the effect of soil tillage and of amounts of plant residue on surface roughness of an Oxisol under simulated rain. Treatments consisted of the combination of the tillage systems of no-tillage (NT, conventional tillage (CT, and minimum tillage (MT with rates of plant residue of 0, 1, and 2 Mg ha-1 of oats (Avena strigosa Schreb and 0, 3, and 6 Mg ha-1 of maize (Zea mays L.. Seven simulated rains were applied on each experimental plot, with intensity of 60±2 mm h-1 and duration of 1 h at weekly intervals. The values of the random roughness index ranged from 2.94 to 17.71 mm in oats, and from 5.91 to 20.37 mm in maize, showing that CT and MT are effective in increasing soil surface roughness. It was seen that soil tillage operations carried out with the chisel plow and the leveling disk harrow are more effective in increasing soil roughness than those carried out with the heavy disk harrow and leveling disk harrow. The roughness index of the soil surface decreases exponentially with the increase in the rainfall volume applied under conditions of no tillage without soil cover, conventional tillage, and minimum tillage. The oat and maize crop residue present on the soil surface is effective in maintaining the roughness of the soil surface under no-tillage.

  14. To Evaluate the Efficacy of an Innovative Irrigant on Smear Layer Removal – SEM Analysis

    Science.gov (United States)

    Sukumaran, Vridhachalam Ganapathy; Subbiya, Arunajatesan

    2016-01-01

    Introduction The goal of endodontic therapy is to completely eliminate the microorganisms and the smear layer from the root canal in order to provide a good seal of the root filling materials. Aim The aim of this study was to find a viable alternative irrigant, which is easily available with less erosion and clinically acceptable smear layer removal by comparing the efficacy of EDTA and commercially available super-oxidized water, named Oxum, as a final rinse on smear layer removal and erosion in relation to coronal, middle and apical thirds of radicular dentin using Scanning Electron Microscope (SEM) analysis. Materials and Methods Freshly extracted 30 human lower second premolar teeth with straight roots and type I canal anatomy were selected. The root canals were cleaned and shaped using Universal Protaper Rotary System. Irrigation was performed with 1 ml of 2.5% of NaOCl solution after each instrument change. The final irrigation (5 ml) sequence was as follows: Group I- 17% EDTA, Group II – OXUM, and Group III - 0.9% saline (control) for one minute. Then, the root canals were finally irrigated with 5ml of distilled water to remove any precipitate. The roots were then gently split into two halves using a chisel and subjected to SEM analysis. Results The SEM photomicrographs were evaluated by two independent examiners and Mann Whitney results showed that there was no statistically significant difference between the two examiners. Non-parametric statistical analysis of all experimental groups showed significant difference between coronal, middle and apical third for smear layer removal with p-value<0.05. For erosion, in group II (oxum) showed statistically significant difference between coronal, middle and apical third and it showed significantly less dentine erosion when compared to EDTA. Conclusion Within the limitations of the present study, Oxum the commercially available super-oxidized water proved to be equally effective in smear layer removal with less

  15. Incidence & Prevalence of Silicotuberculosis in Western Rajasthan: A Retrospective Study of Three Years

    Directory of Open Access Journals (Sweden)

    Kulbeer Chopra, Prabhu Prakash, Suman Bhansali, Arvind Mathur, P K Gupta

    2012-01-01

    Full Text Available Silicosis is a form of pneumoconiosis. It results from inhalation of dust containing crystalline Silica particles of size 0.5 - 5 microns in diameter. Prevalence of Pulmonary Tuberculosis in Silicotics is more common when compared to prevalence in general population. This entity is called Silico-tuberculosis. Study was conducted in Kamla Nehru Chest Hospital attached with Dr.SNMC Jodhpur, among 300 stone mine workers of sand stone mines of Jodhpur with clinico-radiological evidence of Silico-tuberculosis. Workers were divided into 3 categories cutter / driller involved in blasting and cutting stones, dresser engaged in fine work by chisel and Labourer - Loading and Unloading of Stones in Mines .All studied patients were males, majority of cases belong to 21-55 years (93% age group. Among these cases maximum no. of patients belong to 46-50 yr. (18% age group. This is the most economically productive age group in India. With increase in duration of exposure from (0-20 years to Silica particles there is increase in the no. of silico-tuberculosis. After 20 year of exposure there is decrease in no. of cases because cases do not survive upto that long period. 137 patients out of 300 cases were confirmed Acid Fast Bacilli positive by smear examination. 123 patients out of 300 cases were bacteriologically confirmed by culture. Out of 123 culture positive cases 66 (53.65% were typical Mycobacteria& 57 (46.34% were Atypical Mycobacterium. M. Kansasii(28, M. Scrofulaceum ( 9 ,M. Ulcerans(1 M. Fortuitum ( 19, When radiological pattern of Typical Mycobacteria cases and Atypical Mycobacterial cases were confirmed compared we found that Cavity with Nodulation, Pleural Reaction, Progressive Massive Fibrosis, Lower Lobe Involvement, Pnemothorax they all were more common in Atypical than Typical Mycobacteria. M.Kansasii predominantly grown in mining area all around the world. Prevalence of Pulmonary Tuberculosis in Silicotics is more common when compared to

  16. The WELSONS experiment: overview and presentation of first results on the surface atmospheric boundary-layer in semiarid Spain

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    J.-P. Frangi

    Full Text Available This study presents the preliminary results of the local energy budget and dynamic characteristics of the surface atmospheric boundary-layer (SBL during the WELSONS (wind erosion and losses of soil nutrients in semiarid Spain experiment. Some Mediterranean regions suffer land degradation by wind erosion as a consequence of their particular soil and climate conditions and inappropriate agricultural practice. In Spain, where land degradation by water erosion is well known, the lack of field studies to quantify soils losses by wind erosion resulted in the European Community organizing a scientific program for this specific issue. The European programme known as WELSONS was devoted to study the wind erosion process in central Aragon (NE Spain. This multidisciplinary experiment, which began in 1996 and finished in 1998, was carried out over an agricultural soil which was left fallow. Within the experimental field, two plots were delimited where two tillage treatments were applied, a mould-board ploughing (or conventional tillage denoted CT and chisel ploughing (reduced tillage denoted RT. This was to study on bare soil the influence of tillage method on surface conditions, saltation flux, vertical dust flux, erosion rates, dynamics characteristics such as friction velocity, roughness length, etc., and energy budget. The partitioning of the available energy, resulting from the dynamics of the SBL, are quite different over the two plots because of their own peculiar soil and surface properties. The first results show that the RT treatment seems to provide a wind erosion protection. Because of the long data recording time and particular phenomena (formation of a crust at the soil surface, very dry conditions, high wind speed for instance, these microclimatological data acquired during the WELSONS programmes may be helpful to test atmospheric boundary-layer models coupled with soil models.

    Key words: Hydrology (desertification - Meterology and

  17. Effects of tillage methods, corn residue mulch and n fertilizer levels on the wheat crop productivity under the rain fed condition of loess plateau china

    International Nuclear Information System (INIS)

    A 2 years study was conducted to assess the effects of different tillage methods (Chisel plough tillage, Zero-tillage, Rotary tillage and Mould board plough tillage), two mulch levels (M0 i.e. No corn residue mulch and M1 i.e. Corn residue mulch) and 5 N fertilizer levels (0, 80, 160, 240 and 320 kg N/ha) on the wheat crop productivity under the rain fed condition of Loess Plateau, China. Factorial experiment with three replications, having strip, split-split arrangement, with tillage methods in the main plots, mulch levels in sub- plots and N-fertilizer levels in the sub-sub plots was used for this study. Due to variations in rainfalls, during the year, 2010-11, maximum grain yields i.e. 6.58 t/ha and 6.72 t/ha were recorded in case of Zero tillage planting method and similarly in case of 80 kg N/ha, while during the cropping year 2011-12 equal grain yields were recorded in case of all tillage methods, however maximum grain yield (7.46 t /ha) was recorded in case of 320 kg N/ha, N fertilizer level. On two years average basis, maximum grain yields i.e. 6.75 t/ha and 6.80 t/ha were recorded in case of Zero tillage planting method and similarly in case of 80 kg N/ha as compared with the other tillage methods or N fertilizer levels. Use of mulch reduced > 40% weeds infestation. Economic analysis shows that Zero tillage and minimum use of N fertilizer according to the projected rainfalls along with the use of mulch are both economic and environmental friendly. (author)

  18. Shear bond strength of orthodontic brackets after acid-etched and erbium-doped yttrium aluminum garnet laser-etched

    Directory of Open Access Journals (Sweden)

    Shiva Alavi

    2014-01-01

    Full Text Available Background: Laser ablation has been suggested as an alternative method to acid etching; however, previous studies have obtained contrasting results. The purpose of this study was to compare the shear bond strength (SBS and fracture mode of orthodontic brackets that are bonded to enamel etched with acid and erbium-doped yttrium aluminum garnet (Er:YAG laser. Materials and Methods: In this experimental in vitro study, buccal surfaces of 15 non-carious human premolars were divided into mesial and distal regions. Randomly, one of the regions was etched with 37% phosphoric acid for 15 s and another region irradiated with Er:YAG laser at 100 mJ energy and 20 Hz frequency for 20 s. Stainless steel brackets were then bonded using Transbond XT, following which all the samples were stored in distilled water for 24 h and then subjected to 500 thermal cycles. SBS was tested by a chisel edge, mounted on the crosshead of universal testing machine. After debonding, the teeth were examined under Χ10 magnification and adhesive remnant index (ARI score determined. SBS and ARI scores of the two groups were then compared using t-test and Mann-Whitney U test. Significant level was set at P < 0.05. Results: The mean SBS of the laser group (16.61 ± 7.7 MPa was not significantly different from that of the acid-etched group (18.86 ± 6.09 MPa (P = 0.41. There was no significant difference in the ARI scores between two groups (P = 0.08. However, in the laser group, more adhesive remained on the brackets, which is not suitable for orthodontic purposes. Conclusion: Laser etching at 100 mJ energy produced bond strength similar to acid etching. Therefore, Er:YAG laser may be an alternative method for conventional acid-etching.

  19. Efficacy of various root canal irrigants on removal of smear layer in the primary root canals after hand instrumentation: A scanning electron microscopy study

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    Hariharan V

    2010-01-01

    Full Text Available Aim: The purpose of this in-vitro study is to determine the efficacy of various irrigants in removing the smear layer in primary teeth root canals after hand instrumentation. Materials and Methods: The present study consisted of 30 human primary incisors which were sectioned at the cementoenamel junction horizontally. The specimens were divided randomly into four experimental and one control group having six teeth each and each group was treated with the specific irrigant. 5.25% NaOCl, 5.25% NaOCl + 10% EDTA, 6% citric acid, 2% chlorhexidine, saline (control were the irrigants evaluated for efficacy in removal of smear layer. The specimens were split along the longitudinal axis using a chisel after placing superficial grooves in cementum not extending to the root canal. The exposed surface was subjected to scanning electron microscopic analysis to reveal the efficacy of irrigants in removal of smear layer. The representative areas were evaluated twice at 15 days interval by a single evaluator. The scale for the smear layer removal by Rome et al was modified and used in the present study. Results: The pictures from the scanning electron microscopy showed that among the tested irrigants, citric acid has the best efficacy to remove the smear layer without altering the normal dentinal structures, which was supported by the lowest mean smear scores. The pictures from the 10%EDTA + 5.25% sodium hypochlorite group showed that even though it removed the smear layer, it adversely affected the dentine structure. SEM pictures of the other groups like sodium hypochlorite, chlorhexidine revealed that these irrigants does not have the capacity to remove the smear layer in primary teeth. Conclusions: The results of the present study clearly indicate the superior efficacy of 6% citric acid than the other tested irrigants on removing the smear layer in primary teeth root canals.

  20. Performance evaluation of bolt-cutter system on first Taurus launch

    Science.gov (United States)

    Baban, F.; Williams, R.; Amimoto, S.; Hansen, W.; Bixler, T.

    1994-10-01

    In rapid response to the request of the Space Test and Experimentation Directorate in Space Launch Operations, a launch-critical experimental investigation was conducted to evaluate the performance of a particular bolt-cutter system for separating stages on the first Taurus launch. The tests were to examine the variation of tension preloading on the bolt system and to demonstrate the tolerable margin on this parameter for such launches with the new types of bolts since the preloading was known to vary as much as 12% from a preset value before launch. We planned and carried out the experiment, designed and assembled the fixture to properly simulate flight application, and developed diagnostics. Four bolt cutters were purchased from the manufacturer for these tests, and one was provided by the contractor. In addition to the obvious requirement to demonstrate the successful severing of bolts under varying preloads, ignition-wire current and timing of chisel impact on the bolt were monitored. An optical diagnostic was designed to determine the flyout velocity and kinetic energy of the broken pieces. These latter measurements will be useful in anchoring performance codes simulating and assessing the structural dynamics of the bolt-cutter function for future missions. The tests were conducted successfully and the bolts were severed successfully in all five tests. The preloads were successively lowered from 2,500 lb to 2,250, 2,000, 1,500, and 1,000 lb These tests contributed in a timely manner to the STEP launch decision and to launch mission assurance. They demonstrated important margin to the nominally set 3,200 lb. preload. The entire complicated experimental program from inception to completion was accomplished in less than three weeks.

  1. Stade NPP. Dismantling of the reactor pool

    Energy Technology Data Exchange (ETDEWEB)

    Scharf, Daniel; Dziwis, Joachim [E.ON Anlagenservice GmbH Nukleartechnik, Gelsenkirchen (Germany); Kemp, Lutz-Hagen [KKW Stade GmbH und Co. oHG, Stade (Germany)

    2012-11-01

    Within the scope of the 4{sup th} partial decommissioning permission of Stade NPP the activated and contaminated structures of the reactor pool had to be dismantled in order to gain a completely non-radioactive reactor pool area for the subsequent clearance measurement of the reactor building. In order to achieve the aim it was intended to remove the activated pool liner sheets, its activated framework and several contaminated ventilation channels made of stainless steel, the concrete walls of the reactor pool entirely or in parts depending on their activation level, as well as the remaining activated carbon steel structures of the reactor pool bottom. Embedded in the concrete walls there were several highly contaminated excore tubes and the contaminated pool top edge, which were intended to be removed to its full extent. The contract of the Stade NPP initiated reactor pool dismantling project had been awarded to E.ON Anlagenservice GmbH (EAS) and its subsupplier sat. Kerntechnik GmbH for the concrete dismantling works and was performed as follows. In order to minimize the radiation level in the main working area in accordance with the ALARA principle, the liner sheets and middle parts of its framework were removed by means of angle grinders first, as they were the most dose rate relevant parts. As a result the primary average radiation level in the reactor pool (measured in a distance of 500 mm from the walls) was lowered from 40 {mu}Sv/h to less than 2 {mu}Sv/h. After the minimization of the radiation level in the working area the main dismantling step started with the cutting of the reactor pool walls in blocks by means of diamond rope cutters. Once a concrete block was cut out, it was transported into the fuel pool by means of a crane and crane fork, examined radiologically, marked area by area and segmented to debris by means of an electrical excavator with a hydraulic chisel. Afterwards the debris and carbon steel parts were fractioned and packed for further

  2. Variáveis microbiológicas e produtividade do arroz sob diferentes manejos do solo e água = Microbial variables and productivity of rice under different soil and water managements

    Directory of Open Access Journals (Sweden)

    Orivaldo Arf

    2007-07-01

    Full Text Available O objetivo do trabalho foi verificar o efeito de diferentes manejos de solo (MS e água (MA no cultivo de arroz de terras altas por meio da quantificação do carbono da biomassa microbiana (CBM e do CO2 (C-CO2 liberado, do quociente metabólico (qCO2, da micorrização e da produtividade (PROD. O cultivar utilizado foi o IAC 202 e odelineamento experimental foi em blocos casualizados, sendo 3 MS: plantio direto (PD, grade pesada+grade niveladora (GG, escarificador+grade niveladora (EG e 3 MA: lâmina L0 (sem irrigação, lâmina L1 (irrigação na fase reprodutiva e de maturação e lâmina L2 (irrigação durante todo ciclo, com 4 repetições. As variáveis microbiológicas apresentaram sensibilidade em detectar diferenças entre períodos com bons e irregulares índices pluviométricos, onde PD + L1 mostraram os melhores resultados. Sob a ótica da produtividade e viabilidade econômica, o EG + L1 propiciaram resultados mais satisfatórios para a cultura do arroz.This experiment aimed to verify the effects of differents soil (MSand water (WM managements on upland rice cultivation through microbial biomass carbon (MBC quantification, evoluted CO2 (C-CO2, metabolic quotient (qCO2, micorrhization and crop yield. Cultivar IAC 202 was used. The experimental design was a randomized complete block design, with 3 SM: no-tillage (NT, heavy disk + leveling diskharrowing (HL, and chisel plowing + leveling disk harrowing (CL, plus 3 WM: no irrigation (WD0, water depth 1 (WD1, irrigation at the reproductive and maturation periods and water depth 2 (WD2, irrigation throughout the rice cycle, with four replications. The microbiological variables showed sensitivity in detecting differencesbetween good periods and irregular rainfall, where the NT + WD1 showed best results. However, under the viewpoint of productivity and economic viability, CL + WD1 propitiated the most satisfactory results for rice culture.

  3. The study of the radiation protection of propolis to the radiation effects in mice

    International Nuclear Information System (INIS)

    The profit which radiation brought to the Homo sapiens is very big. But, radiation has even harmful parameter for the human besides one case. After effect on man to the radiation is thought about, the individual of which sensibility is the highest is a fetus. Therefore, even an effects to this fetus is grasped precisely, and protection criterion and resource are decided from the viewpoint of the protection of radiation as well. If it does so, a child and maturitas aren't so difficult as in the protection of radiation and the managerial side. It was examined about control group, propolis administration chisels for medical use group, 1.5 Gy independent exposure group and propolis pluse 1.5 Gy group in this study. It was examined about the protection of radiation of propolis which to malformation, fetal death, arrested development, and so on in the organogenesis (8 days post conception) being done when sensibility is the highest against the teratogenesis. Preimplantation death rate was compared with the control group and the sham control group, and statistical significant difference wasn't recognized by a 1.5 Gy radiation independent exposure group, propolis administration 1.5 Gy radiation exposure group. As for the embryonic death rate, propolis was administered, and obviously embryonic death rate was poorer than the 1.5 Gy independent exposure group, and significant difference was recognized by a 1.5 Gy radiation exposure group (p<0.001). It has a 1.5 Gy radiation exposure group made clear by this research fetal death rate propolis administer more only 1.5 Gy exposure fetal death rate development low (p<0.001). Fetal death rate wasn't recognized by propolis administration group (Sham control). As for the teratogenesis rate, propolis was administered, and the teratogenesis rate of the 1.5 Gy radiation exposure group was higher than the 1.5 Gy radiation independent exposure group. But, this is thought anamorphosis appear by propolis administration so long as there was

  4. A Comparison of the Clinical Efficacy of Extraction of Impacted Mandibular Third Molars Using High-speed ;Air-turbine Drill and the Traditional Dental Method%两种方式拔除下颌第三磨牙阻生的对比研究

    Institute of Scientific and Technical Information of China (English)

    钟守鹏

    2016-01-01

    Objective To evaluate the feasibility and safety of using high-speed air-turbine drill to extract medium and low impacted mandibular third molars. Methods 369 cases were randomly divided into control group and experiment group. Tra-ditional hammer chisel splitting method was used in the control group and high-speed air-turbine drill in the experiment group. Lim-ited mouth opening, postoperative pain and dry sockets were observed. Results The duration of tooth extraction in the experiment group is significantly shorter than that in the control group(P<0. 05). The pain score and limited mouth opening between the two groups demonstrated significant difference(P<0. 05). Also postoperative complications such as dry sockets is obviously lower in the experiment group(P<0. 05). Conclusion The high-speed air-turbine drill shows obvious advantages in the extraction of low and medium impacted mandibular third molars with statistic significance.%目的:评价高速涡轮钻法拔除下颌中、低位阻生智齿的临床可行性及其优越性。方法作者对369颗下颌阻生智齿随机采用凿骨劈冠术(对照组)或高速涡轮钻法(实验组)去除阻力两种拔除方法,进行临床观察分析,记录患者张口受限程度、疼痛程度及干槽症的发病情况。结果实验组手术时间明显比对照组手术时间短,差异有统计学意义(P<0.05)。两组患者疼痛程度和张口受限程度的构成比差异有统计学意义(P<0.05)。两组干槽症的发病率差异有统计学意义(P<0.05),实验组发病率明显低于对照组。结论高速涡轮钻法能显著缩短手术时间,减轻患者术后的疼痛、张口受限、干槽症等不良反应,值得临床推荐。

  5. Set Free by Tragedy

    Directory of Open Access Journals (Sweden)

    G.yang mtsho skyid

    2013-12-01

    Full Text Available I was born in a rural community – Hor Village, Tsho drug (Cuozhou Township, Gcan tsha (Jianzha County, Qinghai Province, China. I graduated from Qinghai Normal University with a BA in English and Tibetan and then found my current job, teaching English at Jianzha County Number One Nationalities' Middle School. I enjoy writing stories because I think they explore social phenomena in ways that other writing can not. This story is based on a traditional Tibetan woman's life who married according to her parents' arrangement. When struck by disaster, she was first helpless, but eventually broke with tradition and achieved success, creating a comfortable life for herself and her family. The winter sky was gray and windy. The village was wrapped in the faint smoke that poured from the chimneys of each house. The Yellow River was very blue and calm, even though a harsh wind blew across it. Despite the bad weather, I was excited and couldn't wait to visit Gang skyid from my village, Hor. Gang skyid wasn't famous, beautiful, or rich. She was a farmer, but her life experiences were worth recording and sharing. I was full of expectations when I went to her home to interview her, but she wasn't there. She was in the ma Ni room, so I immediately went there. When I arrived, she was sitting in the sun, spinning a big prayer wheel by pulling a thick, old rope together with other elder women. They were holding the rope tightly as their hands moved up and down rhythmically. Tugged in this way, the huge prayer wheel rotated slowly in front of the women, as though demonstrating the eternal nature of samsara. Gang skyid nodded slightly and thoughtfully when I asked if I could interview her. I sat down by her with a thankful face and realized her eyes were brimming with tears. I felt my throat become dry as I gazed at her. Her face creased as she closed her eyes, and tears ran down her cheeks. Wrinkles were deeply chiseled in her face, especially her forehead. I

  6. Bioanalytical applications of affinity-based nanotube membranes for sensing and separations

    Science.gov (United States)

    Caicedo, Hector Mario

    2008-11-01

    Nanotechnology has played an important role in the development of research and technology during the last two decades. The contribution of nanotechnology in different fields, along with the versatility of the constructed nanoscale materials, have made nanotechnology one of the most suitable tools to develop particular nanostructures to realize a desired function and application. A nanostructure is simply an entity at the nanometer scale with one, two or three dimensional features. Since nanotechnology covers a broad range of nanoscale materials, to simplify nanotechnology, it can be classified into two categories based on how the nanostructures are prepared: top-down and bottom-up. In the top-down methods, the nanostructures are constructed by chiseling larger bulk materials into entities of smaller size. Conversely, in the bottom-up case, small units are grown or assembled into their desired size and shape. The nanoporous materials specifically have attracted a lot of attention because they can be used for the synthesis of a variety of functional nanostructures of great usefulness in technology. These porous nanostructures usually combine many of the advantages of the top-down and bottom-up methodologies such as flexibility, size controllability, and cost. The research presented in this work utilizes nanoporous membranes to develop porous nanostructured platforms with potential applications in sensing and separations. In particular, this work is centered in fundamental studies for bioanalytical applications of affinity-based nanotube membranes for sensing and separations. A bottom-up methodology like the template synthesis was used to produce silica nanotubes inside of the pores of alumina membrane. The functionalization of the inside walls of these silica nanotube membranes allowed control of the functional behavior and properties of the nanostructured membrane during membrane-based separations and sensing. The general scheme of the work presented here, is

  7. Desempenho de um trator em função do tipo de pneu, da lastragem e da velocidade de trabalho Performance of an tractor as a function of tire type, ballasting and forward speed

    Directory of Open Access Journals (Sweden)

    Afonso Lopes

    2005-04-01

    Full Text Available O trabalho comparou o desempenho de um trator agrícola 4x2 TDA de 89 kW (121cv em função do tipo de pneus (radial, diagonal e de baixa pressão, a condição de lastragem (com e sem água nos pneus e quatro velocidades [V1 (1,84km h-1, V2 (3,18km h-1, V3 (4,57km h-1, V4 (5,04km h-1]. O experimento foi realizado na UNESP-Jaboticabal-SP, em condição de preparo do solo com escarificador de sete hastes a 30cm de profundidade. Os pneus foram do tipo R1, com as seguintes características: [radial (dianteiros-14.9 R 26; traseiros-620/75 R 30 diagonal (dianteiros-14.9-26, traseiros-23.1-30 e BPAF (dianteiros-500/60-26.5; traseiros-700/55-34]. O delineamento experimental foi blocos casualizados, em esquema fatorial 3x2x4, com 24 tratamentos e três repetições. Os resultados evidenciaram vantagens para o trator equipado com pneus radiais.The objective of this study was to compare the performance of the FWD agricultural tractor, equipped with three types of tires (bias ply, radial and low pressure, with and without tire water ballasting, operating in four forward speed. The research was carried out at UNESP, SP, Brazil, with the tractor pulling a chisel plow. A tractor with 89kW (121cv engine power equipped with FWD, was used in the experiment, and the tires used had the following characteristics: radial (front: 14.9R26 and rear: 620/75R30, bias ply (front: 14.9-26 and rear: 23.1-30 and low pressure (front: 500/60-26.5 and rear: 700/55-34. The experiment was conducted in a completely randomized block, design (3x2x4, with 24 treatments and three replications. The results evidenced advantages for the tractor equipped with radial tires.

  8. Demanda energética na subsolagem realizada antes e depois de diferentes sistemas de preparo periódico do solo Energy demand in the subsoiling performed before and after different systems of periodic soil tillage

    Directory of Open Access Journals (Sweden)

    Nilson Salvador

    2009-12-01

    Full Text Available A subsolagem é uma das operações mecanizadas de elevado custo e demanda energética por área, tradicionalmente utilizada pelos agricultores antes do preparo do solo na descompactação de camadas adensadas. Este trabalho teve como objetivo avaliar a demanda energética na operação de subsolagem realizada antes e depois de diferentes sistemas de preparo periódico num solo classificado como Nitossolo Vermelho Distroférrico. Os sistemas de preparo periódico foram: aração com discos; aração com discos mais uma gradagem de nivelamento; grade aradora; grade aradora mais gradagem de nivelamento e escarificação. O trator utilizado como fonte de potência no experimento foi um Valmet 128 (4x2tda. A demanda energética por área foi menor na subsolagem realizada depois do preparo periódico do solo, proporcionando uma economia de 21,9%. A realização da subsolagem depois do preparo periódico do solo resultou numa diminuição da exigência de força de tração em 21,1% e da potência disponível na barra de tração em 15%.Subsoiling is one of the mechanized operations of high cost and energy demand per area, traditionally utilized by farmers before soil tillage in the decompactation of hardened layers. This research was intended to evaluate the energy demand in the subsoiling operation performed before and after different systems of periodic tillage in a soil classified as Distroferric Red Nitossol. The periodic tillage systems were: plowing with disks; plowing with disks plus one leveling; plowing harrow; plowing harrow plus leveling and chiseling. The tractor utilized as a power source in the experiment was a Valmet 128 (4x2tda. The demand for energy area was lower in subsoiling held after the regular preparation of the soil, providing a saving of 21.9%. The completion of subsoiling after the preparation of the soil resulted in a decrease in demand for power to pull in 21% and 15% of the power available in the bar of traction.

  9. Handling Heavenly Jewels - 35 Years of Antarctic Meteorite Processing at Johnson Space Center

    Science.gov (United States)

    Satterwhite, C. E.; McBridge, K. M.; Harrington, R.; Schwarz, C. M.

    2011-01-01

    The ANSMET program began in 1976, and since that time more than 18,000 meteorites have been processed in the Meteorite Processing Lab at Johnson Space Center in Houston, TX[1]. The meteorites are collected and returned to JSC on a freezer truck and remain frozen until they are initially processed. Initial Processing of Meteorites: Initial processing involves drying the meteorites in a nitrogen glove box for 24 to 48 hours, photographing, measuring, weighing and writing a description of the interior and exterior. The meteorite is broken and a representative sample is sent to the Smithsonian Institution for classification. Newsletter & Requests: Once initial processing has been complete and the meteorites have been classified, the information is published in the Antarctic Meteorite Newsletter[2,3]. The newsletter is published twice yearly and is sent electronically to researchers around the world and is also available on line. Researchers are asked to fill out a request form and submit it to the Meteorite Working Group secretary. All sample requests will be reviewed by either the meteorite curator or the Meteorite Working Group de-pending on the type of meteorite and the research being conducted. Processing for Sample Requests: In the meteorite processing lab, meteorite samples are prepared several different ways. Most samples are prepared as chips obtained by use of stainless steel chisels in a chipping bowl or rock splitter. In special situations where a researcher needs a slab the meteorite samples can be bandsawed in a dry nitrogen glove box with a diamond blade, no liquids are ever introduced into the cabinet. The last type of sample preparation is thin/thick sections. The meteorite thin section lab at JSC can prepare standard 30-micron thin sections, thick sections of variable thickness (100 to 200 microns), or demountable sections using superglue. Information for researchers: It is important that re-searchers fill the sample request form completely, in order

  10. Occupational and environmental mercury exposure among small-scale gold miners in the Talensi-Nabdam District of Ghana's Upper East region.

    Science.gov (United States)

    Paruchuri, Yasaswi; Siuniak, Amanda; Johnson, Nicole; Levin, Elena; Mitchell, Katherine; Goodrich, Jaclyn M; Renne, Elisha P; Basu, Niladri

    2010-11-15

    Mercury use in small-scale gold mining is ubiquitous across Ghana but little is known about the extent to which such activities have contaminated community residents and miners. Here, occupational exposures to elemental mercury (via urine sampling) and dietary exposures to methylmercury (via hair sampling) were assessed among 120 participants recruited from a mining community located in the Talensi-Nabdam District of Ghana's Upper East region during summer 2009. More than one-fifth of the participants had moderately high levels of urinary mercury (>10μg/L) and 5% had urine mercury levels that exceeded the WHO guideline value of 50μg/L. When participants were stratified according to occupation, those active in the mining industry had the highest mercury levels. Specifically, individuals that burned amalgam had urine mercury levels (median: 43.8μg/L; mean ± SD: 171.1±296.5μg/L; n=5) significantly higher than median values measured in mechanical operators (11.6μg/L, n=4), concession managers/owners (5.6μg/L, n=11), excavators that blast and chisel ore (4.9μg/L, n=33), individuals that sift and grind crushed ore (2.2μg/L, n=47), support workers (0.5μg/L, n=14), and those with no role in the mining sector (2.5μg/L, n=6). There was a significant positive Spearman correlation between fish consumption and hair mercury levels (r=0.30) but not with urine mercury (r=0.18) though further studies are needed to document which types of fish are consumed as well as portion sizes. Given that 200,000 people in Ghana are involved in the small-scale gold mining industry and that the numbers are expected to grow in Ghana and many other regions of the world, elucidating mercury exposure pathways in such communities is important to help shape policies and behaviors that may minimize health risks. PMID:20875913

  11. Early Clinical Effectiveness of ER:Yag Laser in Association with the Red Complex of Bacteria in the Initial Treatment of Moderate Chronic Periodontitis

    Directory of Open Access Journals (Sweden)

    Yaneva Bl.

    2014-06-01

    Full Text Available Chronic periodontitis is a result of polymicrobial infection and its treatment aims removal of dental calculus and biofi lm from the periodontal pocket. Many hand and power-driven instruments are created for this purpose. In recent years, lasers are widely discussed tools for periodontal therapy. The aim of the present study is to evaluate the early microbiological and clinical effectiveness of the Er:YAG laser in the treatment of chronic periodontitis. 30 patients with moderate chronic periodontitis were enrolled in the study. Using a split-mouth design they were treated either with Er:YAG laser (chisel tip, 100 mJ, 15 Hz, 5-6 water spray-test group or with Gracey curettes- control group. Probing pocket depth (PPD, gingival recession (GR, clinical attachment level (CAL, bleeding on probing and plaque presence were evaluated at baseline and one month after the therapy. Microbiological samples were taken from the deepest four pockets of each quadrant from 20 randomly selected patients (n = 80. They were evaluated using real time PCR for periodontal pathogens from the red complex (Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia. One month after therapy in the control group PPD decreased from 4.59 mm to 3.36 mm, the CAL gain was 1.09 mm and the reduction of bleeding and plaque - from 87.9% to 33.7% and from 75.9% to 40.9%, respectively. In the test group PPD decreased from 4.58 mm to 3.15 mm, the CAL gain was 1.37mm and the reduction of bleeding and plaque was from 85.6% to 25.9% one month after the treatment. The results were statistically significant in favour of the laser group (p < 0.05. Microbiological analysis revealed that the pathogens from the red complex decreased 3 times in the control and 6 times in the test group. Therefore, the Er:YAG laser demonstrate pronounced early effectiveness in chronic periodontitis treatment and would be appropriate alternative of the conventional periodontal therapy.

  12. Qualidade das operações de preparo de solo por controle estatístico de processo Quality of tillage operations by statistical process control

    Directory of Open Access Journals (Sweden)

    Marcos Milan

    2002-06-01

    Full Text Available A concorrência em escala mundial obriga as empresas a buscar maior eficiência administrativa e operacional. As técnicas de controle estatístico de processo (CEP são uma das ferramentas que permitem a melhoria da qualidade e produtividade nas empresas. Desenvolvido e largamente aplicado nas indústrias, o CEP tem grande potencial de utilização na agropecuária. Tendo em vista o desenvolvimento desse potencial, esse trabalho tem por objetivo avaliar os efeitos da utilização do controle de qualidade em operações agrícolas de preparo do solo para a cultura do milho utilizando-se como ferramenta de análise o CEP. A utilização do controle na operação de escarificação proporcionou redução da variabilidade de dados de profundidade de trabalho média em 38,4% e aumento de 45,0% dos dados desejados. Na gradagem, houve redução de 9,8% dos dados médios de tamanho de torrões, e um aumento de 75,0% de torrões aceitáveis.Agricultural enterprises must have a professional business management and competitive operational techniques to face competition. The statistical process control (SPC technique is one of the tools that improve quality and productivity of the companies. Developed and used in factories, the SPC has a large application potential for farming and stocking. Facing this potential development, the aim of this study was to evaluate the quality control effects on tillage operations using the SPC as an evaluation tool. The quality control for the chisel operation provided a reduction of 38.4% on data average variability and increased desired data to 45.0%. For the harrow operation, provided a reduction of 9.8% of the average diameter, and increased in 75.0% the desired stone diameter rate for the area.

  13. Effects of changes in land use on soil physical properties and soil organic carbon content in a wheat-corn-sunflower crop sequence, in a loam soil of Argentina.

    Science.gov (United States)

    Aparicio, V.; Costa, J. L.

    2012-04-01

    The Argentinean Humid Pampas extend over about 60 million hectares, 90% of which are agricultural lands. The Southeast of the Buenos Aires Province is part of the Humid Pampas, it covers over 1,206,162 hectares, the mean annual temperature is 13.3 °C and the climate is sub-humid. At the present only 6% of the lands are used for pasture. The main activities are agriculture and cattle production. The main crops are wheat, sunflower, corn and soybean. The tillage systems used in the area are: moldboard plow (MP), chisel plow (CP) and no-till (NT). Excessive soil cultivation under MP generates decreases in the levels of soil organic carbon (SOC). The magnitude of such decrease depends on the intensity of the tillage system, the tillage timeliness and the amount and quality of the residues. Adopting NT may reduce the effects of intensive agriculture, through the maintenance and accumulation of SOC. However, there are evidences that, under NT, the bulk density (ρb) in the superficial layers of the soil increases. The soil compaction causes degradation of the soil structure, reduces the soil water availability and reduces the soil hydraulic conductivity. With this scenario and the tendency to increase the surface under NT in the Southeast Humid Pampas, we evaluated the evolution of some soil physical properties and the SOC in a 10-year experiment with a wheat-corn-sunflower rotation. The experiment was carried out in four localities at farmerś fields under three different tillage systems: MP, CP and NT in a randomized complete block design, considering each locality as a block. Each plot had 50 m in width by 100 m length and the treatments were: NT, MP and CP. The results of this experiment have allowed us to verify that: i) the wheat-corn-sunflower crop sequence showed a tendency to reduce the values of bulk density (ρb) but NT increased ρb in the superficial soil layers; ii) the more intensive the tillage system, the higher the change in the mean weight diameter

  14. Stade NPP. Dismantling of the reactor pool

    International Nuclear Information System (INIS)

    Within the scope of the 4th partial decommissioning permission of Stade NPP the activated and contaminated structures of the reactor pool had to be dismantled in order to gain a completely non-radioactive reactor pool area for the subsequent clearance measurement of the reactor building. In order to achieve the aim it was intended to remove the activated pool liner sheets, its activated framework and several contaminated ventilation channels made of stainless steel, the concrete walls of the reactor pool entirely or in parts depending on their activation level, as well as the remaining activated carbon steel structures of the reactor pool bottom. Embedded in the concrete walls there were several highly contaminated excore tubes and the contaminated pool top edge, which were intended to be removed to its full extent. The contract of the Stade NPP initiated reactor pool dismantling project had been awarded to E.ON Anlagenservice GmbH (EAS) and its subsupplier sat. Kerntechnik GmbH for the concrete dismantling works and was performed as follows. In order to minimize the radiation level in the main working area in accordance with the ALARA principle, the liner sheets and middle parts of its framework were removed by means of angle grinders first, as they were the most dose rate relevant parts. As a result the primary average radiation level in the reactor pool (measured in a distance of 500 mm from the walls) was lowered from 40 μSv/h to less than 2 μSv/h. After the minimization of the radiation level in the working area the main dismantling step started with the cutting of the reactor pool walls in blocks by means of diamond rope cutters. Once a concrete block was cut out, it was transported into the fuel pool by means of a crane and crane fork, examined radiologically, marked area by area and segmented to debris by means of an electrical excavator with a hydraulic chisel. Afterwards the debris and carbon steel parts were fractioned and packed for further treatment

  15. Soil tillage conservation and its effect on erosion control, water management and carbon sequestration

    Science.gov (United States)

    Rusu, Dr.; Gus, Dr.; Bogdan, Dr.; Moraru, Dr.; Pop, Dr.; Clapa, Dr.; Pop, Drd.

    2009-04-01

    The energetic function of the soil expressed through the potential energy accumulated through humus, the biogeochemical function (the circuit of the nutrient elements) are significantly influenced by its hydrophysical function and especially by the state of the bedding- consolidation, soil capacity of retaining an optimal quantity of water, and then its gradual disponibility for plant consumption. The understanding of soil functions and management including nutrient production, stocking, filtering and transforming minerals, water , organic matter , gas circuit and furnishing breeding material, all make the basis of human activity, Earth's past, present and especially future. The minimum tillage soil systems - paraplow, chisel or rotary grape - are polyvalent alternatives for basic preparation, germination bed preparation and sowing, for fields and crops with moderate loose requirements being optimized technologies for: soil natural fertility activation and rationalization, reduction of erosion, increasing the accumulation capacity for water and realization of sowing in the optimal period. By continuously applying for 10 years the minimum tillage system in a crop rotation: corn - soy-bean - wheat - potato / rape, an improvement in physical, hydro-physical and biological properties of soil was observed, together with the rebuilt of structure and increase of water permeability of soil. The minimum tillage systems ensure an adequate aerial-hydrical regime for the biological activity intensity and for the nutrients solubility equilibrium. The vegetal material remaining at the soil surface or superficially incorporated has its contribution to intensifying the biological activity, being an important resource of organic matter. The minimum tillage systems rebuild the soil structure, improving the global drainage of soil which allows a rapid infiltration of water in soil. The result is a more productive soil, better protected against wind and water erosion and needing less

  16. 住宅楼发生火灾后的鉴定及加固%Identiifcation and reinforcement of a residential building after the ifre

    Institute of Scientific and Technical Information of China (English)

    殷占忠; 孙源; 王立功

    2016-01-01

    通过对建筑物烧损构件表观现象进行观察,用回弹法检测混凝土构件的碳化深度和混凝土强度,用超声法检测损伤层厚度,使用钢筋位置测定仪对其钢筋数量与保护层厚度进行了检测,根据《火灾后建筑结构鉴定标准》对检测数据进行了分析,对在火灾中烧损的钢筋混凝土梁、柱、楼板和剪力墙进行了烧损等级的评定,以鉴定评定等级为依据,利用对原过火面积剔凿损伤层后采用高强聚合物砂浆修复、外粘型钢加固、粘碳纤维布加固的加固方法对损伤构件进行了补强处理,经过最后的计算发现结构的强度达到了国家标准所规定的设计强度,满足加固的要求。%Through observing the superficial phenomenon of burning building constructional element,testing the carbonation depth and the concrete strength of concrete members with the springback method, detecting damage layer thickness with ultrasound method,testing the quantity of rebar and cover to reinforcement by using reinforcement location tester, according to “the Appraisal Standard of Building Structure After Fire”,we analyzed the test data,evaluated the loss in the fire of the reinforced concrete beam, column,floor and shear wall in the damage grade,and based on the appraisal ratings,repaired with the high strength polymer mortar after the damage layer of the original burning area was chiseled,then sticked steel reinforcement,and sticked carbon fiber cloth reinforce reinforcing method for reinforcement treatment for the injury structural members.Through the final calculation,we found the strength of the structure has reached the national standard of design strength,which met the requirements of the reinforcement.

  17. Effect of soil management on the white grub population and damage in soybean Efeito do manejo de solo na população e nos danos de corós em soja

    Directory of Open Access Journals (Sweden)

    LENITA JACOB OLIVEIRA

    2000-05-01

    Full Text Available To evaluate the effect of soil management systems on population of white grubs, (Phyllophaga cuyabana Moser, and on its damage in soybean, experiments were set up under no-tillage and conventional tillage (one disk plow, and a leveling disk harrow areas. Primary tillage equipment, used in other soil management systems, such as moldboard plow, disk plow, chisel plow and heavy duty disk harrow were also tested. Fluctuation of P. cuyabana population and the extent of its damage to soybean was similar under no-tillage and conventional tillage systems. Results comparing a range of primary tillage equipment showed that it affected soil insect populations differently, depending on the time during the season in which tillage was executed. Larval mortality could mostly be attributed to their exposure to adverse factors, soon after tillage, than to changes in soil conditions. Reduction of white grub population was more evident in plots managed by heavier equipment, such as the moldboard plow. Soil tillage could be one component within the soil pest management system in soybean, however, its use can not be generalized.Foram realizados vários experimentos para avaliar o efeito de diferentes sistemas de manejo de solo na população de corós (Phyllophaga cuyabana Moser, e seus danos em soja, em áreas de plantio direto e de preparo convencional do solo (preparo primário com arado de discos e uma gradagem niveladora. Vários implementos utilizados no preparo primário de solo, como arado de aivecas, arado de discos, escarificador e grade aradora também foram avaliados. A flutuação populacional de corós e a intensidade de dano causado por eles foram similares nas áreas de plantio direto e de preparo convencional. Os implementos de preparo primário do solo afetaram a população de corós diferentemente, dependendo da época em que o preparo de solo foi executado. A mortalidade larval pode ser atribuída mais à exposição a fatores adversos logo ap

  18. Clinical Use of Minimally Invasive Techniques in Extraction of Mandibular First Molar%微创技术在拔除下颌第一磨牙中的应用

    Institute of Scientific and Technical Information of China (English)

    何世海; 李蓓

    2014-01-01

    Objective:To evaluate the superiority of the minimally invasive technology applying in ex-traction of mandibular first molar .Method:126 patients who required having the mandibular first molar ex-tracted were randomly assigned to two groups in this study .Tooth extraction of the observation group used minimally invasive method , the control group used traditional chisel .Then Compare the operation time , intr-aoperative and postoperative complications of the two groups .Result: The data showed that the changes in blood pressure and heart rate caused by stress in patients with minimally invasive extraction group were smal -ler than those of patients with traditional extraction method .In the observation group , the rate of the root frac-ture and the alveolar socket incomplete was lower , intraoperative or postoperative pain of the patients was smaller, the surgery time was shorter .Conclusion:The uncomfortable feeling in patients with minimally in-vasive extraction was significantly lesser than the patients with traditional method .This kind of tooth extrac-tion is superior to the traditional method and it is worthy to be recommended .%目的:探讨应用微创技术拔除下颌第一磨牙的优越性。方法:对要求拔除下颌第一磨牙的126个复杂病例,分别采用微创拔牙法(观察组)与传统劈凿法(对照组)两种方法拔牙,对手术时间、术中和术后并发症进行比较。结果:观察组因紧张而引起的血压、心律变化较小;术中断根率及拔牙窝不完整率观察组明显低于对照组;观察组患者术中痛苦的程度及发生率也不及对照组;术后疼痛肿胀反应对照组多于观察组;观察组拔牙时间缩短。结论:应用微创技术拔除下颌第一磨牙优于传统拔牙方法,值得推广。

  19. Effects of tillage and poultry manure application rates on Salmonella and fecal indicator bacteria concentrations in tiles draining Des Moines Lobe soils.

    Science.gov (United States)

    Hruby, C E; Soupir, M L; Moorman, T B; Shelley, M; Kanwar, R S

    2016-04-15

    Application of poultry manure (PM) to cropland as fertilizer is a common practice in artificially drained regions of the Upper Midwest United States. Tile-waters have the potential to contribute pathogenic bacteria to downstream waters. This 3-year study (2010-2012) was designed to evaluate the impacts of manure management and tillage practices on bacteria losses to drainage tiles under a wide range of field conditions. PM was applied annually in spring, prior to planting corn, at application rates ranging from 5 to 40 kg/ha to achieve target rates of 112 and 224 kg/ha nitrogen (PM1 and PM2). Control plots received no manure (PM0). Each treatment was replicated on three chisel-plowed (CP) plots and one no-till (NT) plot. Tile-water grab samples were collected weekly when tiles were flowing beginning 30 days before manure application to 100 days post application, and additional grab samples were obtained to target the full spectrum of flow conditions. Manure and tile-water samples were analyzed for the pathogen, Salmonella spp. (SALM), and fecal indicator bacteria (FIB), Escherichia coli (EC), and enterococci (ENT). All three bacterial genera were detected more frequently, and at significantly higher concentrations, in tile-waters draining NT plots compared to CP plots. Transport of bacteria to NT tiles was most likely facilitated by macropores, which were significantly more numerous above tiles in NT plots in 2012 as determined by smoke-testing. While post-manure samples contained higher concentrations of bacteria than pre-manure samples, significant differences were not seen between low (PM1) and high (PM2) rates of PM application. The highest concentrations were observed under the NT PM2 plot in 2010 (6.6 × 10(3) cfu/100 mL EC, 6.6 × 10(5) cfu/100 mL ENT, and 2.8 × 10(3) cfu/100 mL SALM). Individual and 30-day geometric mean ENT concentrations correlated more strongly to SALM than EC; however, SALM were present in samples with little or no FIB

  20. Efeito de três sistemas de preparo do solo sobre a rentabilidade econômica da mandioca (Manihot esculenta Crantz = Effects of three tillage systems on economic profitability of cassava crop (Manihot esculenta Crantz

    Directory of Open Access Journals (Sweden)

    Manoel Genildo Pequeno

    2007-07-01

    Full Text Available O objetivo deste estudo foi avaliar a rentabilidade econômica da cultura damandioca em três sistemas de preparo de solo durante os anos agrícolas de 1999/2000 a2002/2003, em Araruna, Estado do Paraná. O delineamento experimental utilizado foi o deblocos completos casualizados, com oito repetições. Os tratamentos foram constituídos deplantio direto; preparo mínimo (escarificação e preparo convencional (aração + gradagemniveladora. A força de tração e o consumo de combustível requeridos nas operações depreparo do solo e de plantio da mandioca foram maiores no sistema de preparoconvencional. Os maiores custos com combustível, preparo do solo e plantio da mandioca, ecusto operacional relativo às culturas de inverno e à cultura da mandioca, bem como a maiorrenda bruta foram observados no sistema de preparo convencional, seguidos pelo preparomínimo e plantio direto. A maior renda líquida e a melhor relação benefício/custo foramobservadas no sistema de preparo convencional que proporcionou maior produtividade deraízes tuberosas em relação aos sistemas de preparo mínimo e de plantio direto.The objective of this paper was to evaluate the economicprofitability of cassava crop submitted to the three soil tillage systems during the years1999/2000 to 2002/2003, in Araruna, state of Parana. The treatments consisted of three soiltillage systems: no-tillage, minimum tillage using chiseling, and conventional tillage withmoldboard plow and disking, arranged in a randomized complete blocks with eightreplications. The traction strength and fuel consumption in the soil tillage and in the cassavasowed operation were more required in the conventional tillage system. The conventionaland the minimum tillage systems showed the highest costs for fuel, soil tillage and cassavasowed. They also presented the highest gross income. The greatest net income and the bestbenefit/cost relation were observed in the conventional tillage system, which

  1. Peculiarity of radioactivity pollution of manufacturing environment gas and oil producing firms of the apsheron region

    International Nuclear Information System (INIS)

    Full text: Present time protection of the biosphere from technogene pollution is the important problem, having common to all mankind value. In circuits of the technogene pollution of the environment the soil is a carrying on link for through soil the contaminants freely go to air environment, in underground waters in plants and in foodstuff of a vegetative and animal genesis. In subsequent these contaminants on the indicated chains by penetrating in an organism of the people render an ill effect on their health. In this plane the radiological contamination of soil introduces still large dangerous. As the radionuclides of soil can render as external radiation, and by getting in an organism with air, water and foodstuff can cause internal radiation. In this plane, for detection of a role of gas and oil producing firms in radiological contamination soil as object of an environment, we conduct researches by a hygienic estimation of radiological contamination of soil of territory of oil-fields OOGE 'Gum adasi' of the Apsheron region. By spectrometric method were studied a natural background radiation and radioactivity of soil of different territories of shop of complex opening-up of oil. Established, that for the raw tank the specific activity reaches 4438-9967 Bk/kg, close of the product repair shop the radioactivity reached 650- 700 micro R/hour. In territory of the region 'Gum adasi', where the waste from cleaning chisel tubes were accumulated, the radioactivity made 600 micro R/hour. These indexes the superior background level is significant. The analysis of power spectrums a gamma of radiations is model from the indicated sites has shown, that the radioactivity is conditioned by isotopes of a radium. The researches have allowed to demonstrate a radioactivity technogene of impurity of rocks to recommend urgent dumping of above-stated waste in bunkers on sites, retracted by it. Thus, was established, that gas and oil producing firms contributing to radiological

  2. Effect of Conversion from Natural Grassland to Arable Land on Soil Carbon Reserve in the Argentinean Rolling Pampas

    Science.gov (United States)

    Andriulo, A. E.; Irizar, A. B.; Mary, B.; Wilson, M. G.

    2012-04-01

    The evaluation of the effect of land use change on accumulation of soil organic carbon (SOC) requires reliable data obtained from georeferenced sites with land use history records. The purpose of this study was to evaluate long term changes in the reserves of SOC in a typical Argiudol of the Pergamino series after the introduction of agriculture. Measures of soil organic carbon concentration and bulk density of Ap and A12 horizons were carried out in three sites of the Pergamino County (N of Buenos Aires province): a reference field with untilled pristine soil (33° 57' S; 60° 34' W), a field with 31 years (1980-2011) of agriculture (31Y) located next to the former, and a third field (33° 46' S; 60° 37' W) with 80 years (1910/1990) of agriculture (80Y). 31Y has been under continuous soybean cultivation with conventional tillage (CT) that consists of moldboard plow or double disk harrowing. At 80K the cultivation sequence was: 44 years of corn + 9 years of flax + 2 years of wheat + 17 years of wheat/soybean double cropping + 1 year of lentil; mostly under CT, some years under chisel plow during the 70's and a few years under zero tillage in soybean after wheat sown with conventional tillage during the 80's. Before the introduction of mechanical harvesting (1947) crop residues were burnt as well as the wheat stubble during the conventional double cropping period (1970-1980). Soil texture (23±1% clay, with predominance of illite) and field slopes (<0.5%) were similar in the three sites. Nitrogen and phosphorus fertilization rates were minimal due to the low crop response. The results are expressed in Mg ha-1 for an A soil horizon mass of 2500 Mg ha-1. The introduction of agriculture decreased SOC stock: 31Y varied from 68.3 to 40.1 Mg ha-1 (41.3% loss) and 80Y from 68.3 to 47.2 Mg ha-1 (30% loss). The SOC loss was the result of the mineralization of a large amount labile SOC present in the pristine soil and low annual additions of carbon issued from crop residue

  3. Dismantling of a hot cell-block and the treatment of the produced concrete bars

    International Nuclear Information System (INIS)

    A building with hot cells had been operated in Karlstein/Main from 1968 to 1989 in order to perform check-ups at radiated fuel rods and nuclear components. The operation of the system was stopped after an operation period of approximately 20 years. The core part of the building to be disassembled is a U-shaped hot cell-block with nine individual cells, partly consisting of heavy reinforced concrete, located in the ground floor (fig. 1 and fig. 2). The major part of the cells was covered with 10 mm steel plate and provided with approx. 1,400 openings of all different kinds. The wall thickness of the cells was between 0.90 m and 1.10 m. Under these conditions a successful decontamination at the ''existing building structure'' was not possible. Therefore, the non-supporting structures of the hot cell-block were removed in individual blocks by means of sawing and the remaining walls and floors were peeled by using the diamond rope sawing technique. The dismantling took 17 months. A re-treatment of the produced concrete blocks (235 blocks, approx. 970 Mg) to reduce the radioactive waste to a minimum was performed at the Research Centre Karlsruhe, Central Decontamination Department (HDB). The Target of the concrete bar treatment at HDB is to reduce the volume of radioactive waste to a minimum and to add the major part of the concrete bars to harmless utilisation. To achieve the same, initially the more contaminated parts of the bars without openings, such as tubes, cable or ventilating shafts, are removed by means of wire cutting and packed into a KONRAD-Container as radioactive waste. The remaining bar is decontaminated by means of sandblasting and afterwards, following successful release measurement, released from the scope of the regulations under the Atomic Energy. Bars with openings are crushed into small pieces by means of the remote-controlled chisel excavator, in order to separate the individual kinds of material. The rubble is packed into drums and measured by

  4. Consumo de combustível de um trator em função do tipo de pneu, da lastragem e da velocidade de trabalho Fuel consumption of a tractor as a function of the tyre type, ballasting and forward speed

    Directory of Open Access Journals (Sweden)

    Afonso Lopes

    2003-08-01

    Full Text Available Com o presente trabalho, teve-se como objetivo comparar o consumo de combustível de um trator agrícola operando com pneus (radial, diagonal e de baixa pressão em duas condições de lastragem (com e sem água nos pneus e quatro velocidades de deslocamento. O experimento foi realizado na FCAV-UNESP, Jaboticabal, SP, em condição de preparo do solo com escarificador. Utilizou-se um trator 4x2 TDA, com potência de 89 kW (121 CV no motor. Os pneus foram do tipo R1, com as seguintes características: radial (dianteiros: 14.9 R 26; traseiros: 620/75 R 30 diagonal (dianteiros: 14.9-26, traseiros: 23.1-30 e BPAF (dianteiros: 500/60-26.5; traseiros: 700/55-34. O delineamento experimental foi o de blocos casualizados, em esquema fatorial 3x2x4, com 24 tratamentos e 3 repetições. Os resultados evidenciaram vantagens para o trator quando equipado com pneus radiais. A condição de lastragem com água nos pneus ofereceu menor consumo específico. Observou-se também que o aumento da velocidade de deslocamento reduziu o consumo específico.The objective of this study was to compare the consumption of fuel of the FWD agricultural tractor, equipped with three types of tyres (bias ply, radial and low pressure, with and without tyre water ballasting, operating in four forward speeds. The research was carried out at FCAV/UNESP, SP, Brazil, The soil was tilled using a chisel plow. A tractor with 89 kW (121 HP engine power equipped with FWD was used in the experiment, and the tyres used had the following characteristics: radial (front: 14.9R26 and rear: 620/75R30, bias ply (front: 14.9-26 and rear: 23.1-30 and low pressure (front: 500/60-26.5 and rear: 700/55-34. The experiment was conducted in a completely randomized block design (3x2x4, with a total of 24 treatments and three replications. The results evidenced advantages for the tractor equipped with radial tyres. The ballasting condition with water in the tyres showed lower specific consumption. It was

  5. Influence of Soil Tillage Systems on Soil Respiration and Production on Wheat, Maize and Soybean Crop

    Science.gov (United States)

    Moraru, P. I.; Rusu, T.

    2012-04-01

    Soil respiration leads to CO2 emissions from soil to the atmosphere, in significant amounts for the global carbon cycle. Soil capacity to produce CO2 varies depending on soil, season, intensity and quality of agrotechnical tillage, soil water, cultivated plant, fertilizer etc. The data presented in this paper were obtained on argic-stagnic Faeoziom (SRTS, 2003). These areas were was our research, presents a medium multiannual temperature of 8.20C, medium of multiannual rain drowns: 613 mm. The experimental variants chosen were: A. Conventional system (CS): V1-reversible plough (22-25 cm)+rotary grape (8-10 cm); B. Minimum tillage system (MT): V2 - paraplow (18-22 cm) + rotary grape (8-10 cm); V3 - chisel (18-22 cm) + rotary grape (8-10 cm);V4 - rotary grape (10-12 cm); C. No-Tillage systems (NT): V5 - direct sowing. The experimental design was a split-plot design with three replications. In one variant the area of a plot was 300 m2. The experimental variants were studied in the 3 years crop rotation: maize - soy-bean - autumn wheat. To soil respiration under different tillage practices, determinations were made for each crop in four vegetative stages (spring, 5-6 leaves, bean forming, harvest) using ACE Automated Soil CO2 Exchange System. Soil respiration varies throughout the year for all three crops of rotation, with a maximum in late spring (1383 to 2480 mmoli m-2s-1) and another in fall (2141 to 2350 mmoli m-2s-1). The determinations confirm the effect of soil tillage system on soil respiration, the daily average is lower at NT (315-1914 mmoli m-2s-1), followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Productions obtained at MT and NT don't have significant differences at wheat and are higher at soybean. The differences in crop yields are recorded at maize and can be a direct consequence of loosening, mineralization and intensive mobilization of soil fertility. Acknowledgments: This work was supported by CNCSIS

  6. Variscita y ámbar en el Neolítico gallego. Análisis arqueométrico del collar del túmulo 1 de Chousa Nova, Silleda (Pontevedra, España

    Directory of Open Access Journals (Sweden)

    Domínguez-Bella, Salvador

    2011-12-01

    Full Text Available The excavation of barrow 1 of Chousa Nova, Silleda, Pontevedra (NW Spain offered surprising results. This mound, in spite of experiencing a large number and types of anthropic damage, still preserved a great constructive complexity. Within its megalithic chamber, formed by 5 granite orthostats and a large roofing slab of, also in granite, a set of archaeological materials appeared. These were an axe, a chisel and a polishing stone, with a set of 35 beads, most of them of a green stone and the rest of an organic material, with an extremely high degree of alteration, inserted between them. The analytical techniques have been in all cases not-destructives (X-ray diffraction and fluorescence spectroscopy, infrared spectroscopy, optical microscopy and environmental electronic microscopy, with microanalysis. The archaeometric analysis results show a mineralogical nature of these materials, based in variscite and amber. The textural and compositional features are very homogeneous between each assemblage of beads. The importance of the alteration phenomena and dissolution of the archaeological objects are determined and quantified. This alteration is due to an intense chemical attack during the burial periods. The possible source areas of provenance for these materials are also discussed on the basis of geochemical data obtained in the analysis.

    La excavación del túmulo 1 de Chousa Nova, Silleda (Pontevedra, proporcionó unos resultados sorprendentes. Aunque muy deteriorado, por diferentes factores, conservaba evidencias de una gran complejidad constructiva. Dentro de su cámara megalítica apareció, junto con otros objetos pulidos, un conjunto de 35 cuentas dispuestas a modo de collar. Se han estudiado todas, unas de color verde y otras de carácter orgánico, intercaladas entre ellas. Los resultados del análisis arqueométrico mediante técnicas no-destructivas (difracción y fluorescencia de Rayos X, espectroscopía de infrarrojos

  7. FY 2016 Status Report: CIRFT Testing Data Analyses and Updated Curvature Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-01

    This report provides a detailed description of FY15 test result corrections/analysis based on the FY16 Cyclic Integrated Reversible-Bending Fatigue Tester (CIRFT) test program methodology update used to evaluate the vibration integrity of spent nuclear fuel (SNF) under normal transportation conditions. The CIRFT consists of a U-frame testing setup and a real-time curvature measurement method. The threecomponent U-frame setup of the CIRFT has two rigid arms and linkages to a universal testing machine. The curvature of rod bending is obtained through a three-point deflection measurement method. Three linear variable differential transformers (LVDTs) are used and clamped to the side connecting plates of the U-frame to capture the deformation of the rod. The contact-based measurement, or three-LVDT-based curvature measurement system, on SNF rods has been proven to be quite reliable in CIRFT testing. However, how the LVDT head contacts the SNF rod may have a significant effect on the curvature measurement, depending on the magnitude and direction of rod curvature. It has been demonstrated that the contact/curvature issues can be corrected by using a correction on the sensor spacing. The sensor spacing defines the separation of the three LVDT probes and is a critical quantity in calculating the rod curvature once the deflections are obtained. The sensor spacing correction can be determined by using chisel-type probes. The method has been critically examined this year and has been shown to be difficult to implement in a hot cell environment and thus cannot be implemented effectively. A correction based on the proposed equivalent gauge-length has the required flexibility and accuracy and can be appropriately used as a correction factor. The correction method based on the equivalent gauge length has been successfully demonstrated in CIRFT data analysis for the dynamic tests conducted on Limerick (LMK) (17 tests), North Anna (NA) (6 tests), and Catawba mixed oxide (MOX) (10

  8. Correção da acidez do solo em função de modos de incorporação de calcário Correction of soil acidity in function of lime incorporation manners

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Weirich Neto

    2000-04-01

    dystrophic Dark Red Latosol, in native field. A randomized complete block design was used, with three replications, in a split-plot experiment. The treatments consisted of five incorporation methods: disk plowing plus two spring disk harrowing, off-set harrowing plus two spring disk harrowing, rotary tilling, chisel plowing plus two spring disk harrowing and lime distribution on the surface without incorporation (main plots, and four rates of dolomitic limestone: 0, 2.8, 6.6 and 10.3 t ha-1, in order to raise base saturation of soil to 30, 60 and 90% (subplots. The cultivated plant was maize. The results showed that the lime incorporation manner in the soil affects its efficiency in relation to the depth in the profile in which there is neutralization of the acidity. There was elevation in base saturation of the soil to the layer of 20cm, 15cm and 10cm, respectively, for the following incorporation manners: rotary tilling, disk plowing or off-set harrowing and chisel plowing or lime distribution on the surface without incorporation. The saturation values for wanted bases were not reached, three months after liming, independent in the incorporation manner of lime.

  9. Foldable Instrumented Bits for Ultrasonic/Sonic Penetrators

    Science.gov (United States)

    Bar-Cohen, Yoseph; Badescu, Mircea; Iskenderian, Theodore; Sherrit, Stewart; Bao, Xiaoqi; Linderman, Randel

    2010-01-01

    Long tool bits are undergoing development that can be stowed compactly until used as rock- or ground-penetrating probes actuated by ultrasonic/sonic mechanisms. These bits are designed to be folded or rolled into compact form for transport to exploration sites, where they are to be connected to their ultrasonic/ sonic actuation mechanisms and unfolded or unrolled to their full lengths for penetrating ground or rock to relatively large depths. These bits can be designed to acquire rock or soil samples and/or to be equipped with sensors for measuring properties of rock or soil in situ. These bits can also be designed to be withdrawn from the ground, restowed, and transported for reuse at different exploration sites. Apparatuses based on the concept of a probe actuated by an ultrasonic/sonic mechanism have been described in numerous prior NASA Tech Briefs articles, the most recent and relevant being "Ultrasonic/ Sonic Impacting Penetrators" (NPO-41666) NASA Tech Briefs, Vol. 32, No. 4 (April 2008), page 58. All of those apparatuses are variations on the basic theme of the earliest ones, denoted ultrasonic/sonic drill corers (USDCs). To recapitulate: An apparatus of this type includes a lightweight, low-power, piezoelectrically driven actuator in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary twist drilling, ordinary hammering, or ordinary steady pushing. Examples of properties that could be measured by use of an instrumented tool bit include electrical conductivity, permittivity, magnetic

  10. Research and Development of 2 BMYF-4 Intelligent No-till Maize Planter and its Field Experiment%2 BMFY-4型玉米免耕播种机研制与试验

    Institute of Scientific and Technical Information of China (English)

    杨自栋; 杜瑞成; 马明建; 蔡善儒; 刘宁宁

    2014-01-01

    Based on the agronomic characteristics with yearly maize-wheat rotation and large amount of straw cover after wheat harvesting and blocking during no-till maizeplanting in Shandong Province , a new-concept no-till wheat-maize planter , named 2 BMYF-4 intelligent no-till maize planter , has been researched and developed by researchers from Shandong University of Technology to solve some extremely important problems , such as chopping and covering standing wheat stubble in one-stop operation in double cropping areas of Shandong Province in China .The combined anti-bloc-king device composed of powered chopping axle and the planting unit with chisel opener was designed .The planting spacing regulation transmission was used to meet the needs of different planting densities .In order to meet the require-ments of automatic monitoring of farming quality and quantity of large scale precision seeders , an intelligent system with video monitor function for gauging and monitoring seed and fertilizer was researched and developed .Field performance test results at Zhangqiu , Zhangdian and Zhoucun showed that this planter could accomplish many procedures , such as stubble chopping , furrow opening , seed and fertilizer placement , suppressing , etc, in one-stop operation , thus the oper-ation cost could be reduced by about 30%.The machine worked very well for planting maize while shattering standing wheat stubble .The powered chopping axle resolved the anti-blockage problem ahead of shank , and the double-chisel o-pener unit reduced the blockage between planting units , thus the cross-country ability of the planter was improved . Meanwhile, the coefficients of variation(CV) for fertilizer and seed depth were reduced to 17.2%and 18.6%, respec-tively.The free-swinging knife of the planter can cut straw stubble in shallow soil with less than 20% soil breakage , which can prevent soil degradation .Therefore , this machine will be a good solution to no-till wheat-maize planting in

  11. A SOLUÇÃO DO SOLO DE UM LATOSSOLO VERMELHO DISTRÓFICO SUBMETIDO A TRÊS TIPOS DE MANEJO DE SOLO E DE CULTURAS

    Directory of Open Access Journals (Sweden)

    Silvio Tulio Spera

    2014-06-01

    -tillage (PD, minimum cultivation with chisel plow (PM and conventional plowing with disk plow (PC. These were combined with crop rotations: wheat-soybean (R1; wheat-soybean/common vetch-sorghum (R2 and wheat-soybean/common vetch-sorghum/white oats-soybean (R3, to assess the interaction effect of these rotations with the type of soil management in the chemical attributes of soil solution in layers of 0 to 6.7 cm and 6.8 to 20 cm. There were no correlations between the soil attributes evaluated on both layers, even when differences in levels of chemical and physical constraint between the layers. Chemical attributes of soil solution were not influenced by the interaction of the studied factors, being slightly influenced by crop rotation. The no-till provided the greatest values of dissolved organic carbon and Al lowest level and activity in soil solution, promoting the Al toxicity. Keywords: soil nutrients; no-till, soil plowing, soil chemistry.DOI: http://dx.doi.org/10.14583/2318-7670.v02n02a01 

  12. Dinâmica do banco de sementes de plantas daninhas sob diferentes sistemas de manejo de solo Weed seedbank dynamics under different soil management systems

    Directory of Open Access Journals (Sweden)

    E. Voll

    2001-08-01

    Full Text Available Um experimento foi conduzido em campo no período de 1982 a 1998, em Londrina-PR, com o objetivo de avaliar o efeito de diferentes sistemas de manejo de solo nas reduções anuais de um banco de sementes de plantas daninhas e seus períodos de sobrevivência, sendo as plantas daninhas manejadas através de herbicidas, e a seqüência anual de cultivo soja após trigo. Os tratamentos de manejo de solos foram: 1 semeadura direta; 2 arado de discos e grade niveladora; 3 grade aradora e grade niveladora; 4 escarificação e grade niveladora. O delineamento experimental foi o de blocos ao acaso, com quatro repetições. A identificação e contagem das sementes presentes no solo foram feitas em 1990, 1995 e 1998. As estimativas de sobrevivência (a 1% da população inicial das gramíneas capim-marmelada (Brachiaria plantaginea e capim-colchão (Digitaria horizontalis , nos quatro sistemas de manejo, foram de 5 a 10 anos e 5 a 7 anos, respectivamente; as das espécies de folhas largas, como caruru (Amaranthus spp., de 5 a 9 anos, carrapicho-de-carneiro (Acanthospermum hispidum , de 7 a 9 anos, de 10 a 20 anos, e picão-preto (Bidens pilosa, de 3 a 4 anos, e a comelinácea trapoeraba (Commelina benghalensis de 10 a 20 anos. As sementes de espécies de plantas daninhas apresentaram características distintas de sobrevivência, em função do manejo do solo, do controle ao longo dos anos e das características morfológicas e fisiológicas das sementes.A field experiment was conducted from 1982 to 1998, in Londrina-PR, Brazil, to evaluate the effects of different soil management systems on the survival of a weed seedbank, with the weeds managed by herbicides, and the annual sequence of crops consisting of soybean - wheat. The soil management treatments were: 1 no-till; 2 mouldboard; 3 heavy disc, and 4 chisel. The experimental design was a randomized complete block, with four replications. Seed identification and counting were performed in 1990, 1995

  13. Alterações microbiológicas, de fertilidade e de produtividade do arroz de terras altas em diferentes manejos de solo e água = Microbiological, fertility and productivity alterations in upland rice under different soil and water managements

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    Talles Eduardo Borges dos Santos

    2008-04-01

    BRS Talento was used in the experiment. The experimental design was a completely randomized block design, with four replications, using three soil managements: no-tillage (NT, heavy disk + leveling disk harrowing (HL, and chisel plowing + leveling disk harrowing (CL, plus three water managements: no irrigation (WD0; water depth 1 (WD1, with irrigation at the reproductive and maturation periods; and water depth 2 (WD2, with irrigation throughout the rice cycle. Autochthones arbuscular mycorrhizal fungi proved to be sensitive to soil and water management. The NT presented the highest values for MO, Ca, SB and V% and the lowest for H+Al. This management, together with irrigation at the reproductive and maturation periods of BRS Talento cultivar, promoted goods results for crop yield and microbiology characteristics.

  14. Assessing Tillage Effects on Soil Hydraulic Properties via Inverse Parameter Estimation using Tension Infiltrometry

    Science.gov (United States)

    Schwen, Andreas; Bodner, Gernot; Loiskandl, Willibald

    2010-05-01

    Hydraulic properties are key factors controlling water and solute movement in soils. While several recent studies have focused on the assessment of the spatial variability of hydraulic properties, the temporal dynamics are commonly not taken into account, primarily because its measurement is costly and time-consuming. However, there is extensive empirical evidence that these properties are subject to temporal changes, particularly in the near-saturated range where soil structure strongly influences water flow. One main source of temporal variability is soil tillage. It can improve macroporosity by loosening the soil and thereby changing the pore-size distribution. Since these modifications are quite unstable over time, the pore space partially collapses after tillage. This effect should be largest for conventional tillage (CT), where the soil is ploughed after harvest every year. Assessing the effect of different tillage treatments on the temporal variability of hydraulic properties requires adequate measurement techniques. Tension infiltrometry has become a popular and convenient method providing not only the hydraulic conductivity function but also the soil rentention properties. The inverse estimation of parameters from infiltration measurements remains challenging, despite some progress since the first approach of Šimůnek et al. (1998). Measured data like the cumulative infiltration, the initial and final volumetric water content, as well as independently measured retention data from soil core analysis with laboratory methods, have to be considered to find an optimum solution describing the soil's pore space. In the present study we analysed tension infiltration measurements obtained several times between August 2008 and December 2009 on an arable field in the Moravian Basin, Lower Austria. The tillage treatments were conventional tillage including ploughing (CT), reduced tillage with chisel only (RT), and no-tillage treatment using a direct seeding

  15. 高速涡轮机在下颌多根阻生智齿拔除术中的应用%Application of high-speed turbine in dental extraction with mandibular multiple resistance

    Institute of Scientific and Technical Information of China (English)

    杨益华; 王仁飞

    2014-01-01

    Objective To explore the application of high-speed turbine in dental extraction with mandibular multiple resistance in minimally invasive. Methods In the observation group,the no fear rate was 77.22%, which was significantly higher than that in the control group (21.52%) (P<0.05). The operation time in observation group was (14.87±3.13)min, which was significantly shorter than that in control group(P<0.05). The postoperative swelling, pain score, tooth nest integrity and limitation of mouth opening degree in observation group were significantly lower than that in control group (P<0.05). The postoperative satisfaction score in observation group was (8.89 ±1.61), which was significantly higher than that in control group(P<0.05). The total adverse reaction rate in observation group was 6.39%, which was significantly lower than 17.72% in the control group (P<0.05). Conclusion Comparing to the traditional instrument hammer and chisel, high speed turbine applied to extract mandibular impacted wisdom teeth had a plurality of short operation time, light postoperative pain, high satisfaction, less postoperative complications.%目的:探讨高速涡轮机在微创下颌多根阻生智齿拔除术中的应用。方法选择在本院实施下颌多根阻生智齿拔除的患者158例,根据拔除方式的不同分为对照组和观察组,每组均为79例。对照组常用采用传统拔牙器械锤凿去骨方式拔除,观察组采用高速涡轮机去骨方式拔除。比较两组手术时间、畏惧率、术后疼痛感、满意度、张口受限度、肿胀度、拔牙窝完整性和并发症等。结果观察组患者不畏惧率达到77.22%,显著高于对照组(P<0.05);观察组手术时间仅为(14.87±3.13)分钟,显著短于对照(P<0.05);术后肿胀度、痛度评分、拔牙窝完整性和张口受限度均显著低于对照组(P<0.05);术后观察组满意度评分达到(8.89±1.61),显著高于对照组(P<0.05);

  16. Manejo do solo e o rendimento de soja, milho, feijão e arroz em plantio direto Yield of soybean, corn, common bean and rice under no-tillage management

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    João Kluthcouski

    2000-03-01

    Full Text Available O sistema de plantio direto tem sido adotado expressivamente por agricultores do cerrado brasileiro. Contudo, seu uso continuado em regiões tropicais, com insuficiência de cobertura do solo e sucessivas adubações superficiais, pode resultar em alterações nos parâmetros do solo, como compactação e acúmulo de nutrientes na superfície, e na baixa expressão do potencial produtivo das culturas. O presente estudo teve como objetivo principal verificar o efeito de quatro sistemas de manejo de solo (plantio direto; grade aradora; escarificação profunda e aração profunda associados com três níveis de adubação fosfatada e potássica (sem adubação, recomendação oficial e equivalente a exportação pelas colheitas sobre o rendimento das culturas do milho, soja, feijão e arroz em área submetida a plantio direto durante oito anos. Os experimentos com soja, milho, arroz e feijão foram conduzidos em um Latossolo Roxo eutrófico no esquema de faixas e delineamento de blocos completos casualizados, com quatro repetições. Avaliou-se ainda o rendimento de grãos. Não houve resposta da soja aos diferentes manejos do solo nem aos níveis de adubação. Já a aração profunda resultou nos maiores rendimentos de milho, arroz e feijão, sendo intermediários os efeitos devidos à escarificação. Exceto para o feijão, nestas culturas também não se verificou efeito da adubação.The no-tillage cropping system is widely adopted in the Brazilian savannah region (cerrado. However, the continuous use of this system under tropical conditions with insufficient mulching and successive superficial fertilizations, can alter soil chemical and physical properties, causing problems of soil compaction and excessive accumulation of nutrients in the soil surface layer, decreasing the yield potential. The present study had as main objective to verify the effect of four systems (no tillage; heavy harrowing; deep chiseling and deep moldboard plowing of

  17. NÍVEL DE POTÊNCIA SONORA NAS OPERAÇÕES AGRÍCOLAS

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    CORTEZ, Jorge Wilson

    2011-05-01

    Full Text Available The noise generated by agricultural mechanization brought side effects, and one of them is thedamage the hearing of the operator of agricultural machinery. The NR-15 establishes the limits of tolerance forcontinuous noise, and exposure to the maximum allowable noise level of 115 dB (A for individuals who are notusing individual protection equipment and 85 dB (A, considering a shift work of 8 h. The objective was to studythe influence of working speed and soil condition in agricultural operations in the determination of sound powerlevels emitted by the tractor. The study was conducted at the Center for Agricultural Sciences - UNIVASF,Petrolina / PE using a Valtra tractor model 785 TDA cabin and meter without the sound power level. Weevaluate the sound power level of the tractor in five speeds (3.0, 5.0, 8.7, 10.7 and 13.0 km h-1 on prepared soiland ground covered with weeds, with the equipment: lightweight tandem grid, grid light off-set with discs of55.8 cm, grade mild off-set with discs of 60.8 cm, chisel plow, mower and distributor commuting. The mostsignificant amounts were found in the tractor and plow in operation, noting that the requirement of increasedpower in the engine sound power level.O ruído gerado pela mecanização agrícola trouxe efeitos colaterais, e um deles é o dano à audiçãodo operador de máquinas agrícolas. A NR-15 estabelece os limites de tolerância para os ruídos contínuos, sendoa exposição máxima permitida ao nível de ruído de 115 dB (A para indivíduos que não estejam utilizandoequipamentos de proteção individuais e 85 dB (A, considerando uma jornada de trabalho de 8 h. O objetivodeste trabalho foi estudar a influência da velocidade de trabalho e a condição do solo nas operações agrícolas nadeterminação dos níveis de potência sonora emitido pelo trator. O trabalho foi realizado no Centro de CiênciasAgrárias da UNIVASF, Petrolina/PE utilizando um trator Valtra modelo 785 TDA sem cabine e o

  18. THE CURATIVE EFFECT ANALYSIS OF EXTRACTION OF IMPACTED WISDOM TEETH BY MINIMALLY INVASIVE BONED BICUSPIDIZATION IN BASIC HOSPITAL%微创去骨分牙法拔除下颌阻生智齿在基层医院应用的疗效分析

    Institute of Scientific and Technical Information of China (English)

    史勇勇; 邓智明; 周仕宏; 张铁柱; 彭柏松

    2015-01-01

    Objective To study the curative effect analysis of extraction of impacted wisdom teeth by high speed turbine bodkin minimally invasive boned bicuspidization in basic hospital .Methods 164 outpatient service cases of Low ambush third molars were collected at The Red Cross Hospital of Lianzhou City from May 2013 to May 2015.All the cases were randomly divided into two groups , minimally invasivation group ( MI group) including 82 ca-ses and Conventional surgery group ( CS group ) including 82 cases.Minimally invasive boned bicuspidization was choosed in MI group , and traditional chisel was choosed in CS group .The duration of operations were recorded in all cases.Followed out-patient review at 1, 3, 7 day after operation.We compared the duration of operation , pain, limitation of mouth opening , swelling degree , and the incidence rates of alveolities and congestion and subcutaneous emphysema between two groups .Results The average duration of operation of MI group was less than CS group ( p0.05).The degree of mouth opening limitation of MI group is less than CS group at 1, 3, 7 day after operation.The incidence rates of alveolities congestion and subcutaneous emphyse-ma were no difference between two groups ( p>0.05 ) .Conclusion Extraction of impacted wisdom teeth by mini-mally invasive boned bicuspidization can shorten the duration of operation , and reduce the postoperative complica-tions, and can be applied in basic hospitals .%目的:探讨高速涡轮钻微创去骨分牙法拔除下颌阻生智齿在基层医院应用的疗效。方法收集连州市红十字会医院2013年5月~2015年5月门诊低位埋伏第三磨牙共164例,按随机数字法分为两组:微创组82例;常规组82例。微创组应用高速涡轮钻微创去骨分牙法,常规组应用凿骨劈冠法。所有手术病例均记录手术时间,并于术后第1、3、7天复查。对比分析两组患者手术时间,疼痛、张口受限、肿胀程度,淤血、皮下气

  19. Observation of Application of High-speed Turbine Drills and Original Luxator Tooth Instruments in Impacted Wisdom Tooth Extraction Surgery%高速涡轮机、微创拔牙刀在阻生智齿拔除术中的应用观察

    Institute of Scientific and Technical Information of China (English)

    刘改英; 刘晓波; 张伟

    2015-01-01

    目的:观察在下颌中位近中水平阻生智齿拔除术中应用高速涡轮机、微创拔牙刀的优越性。方法选择因下颌中位近中水平阻生智齿导致下前牙牙列拥挤错位的年轻正畸患牙(者)80例,随机分成2组,研究组和对照组各40例。研究组拔牙器械采用高速涡轮牙钻和微创拔牙刀,对照组采用常规拔牙器械,记录术中牙齿拔除术所需时间、术中及术后7 d复诊时患者的症状。结果研究组平均拔牙时间15.1 min,对照组平均拔牙时间32.5 min,研究组平均拔牙时间明显少于对照组,术中、术后反应及满意度调查中研究组明显高于对照组。结论高速涡轮牙钻和微创拔牙刀在年轻患者下颌中位近中水平阻生智齿拔除术时具有明显优势。%Objective To shorten the tooth extraction time and reduce the postoperative complications, observe the advantage of ap⁃plication of high-speed turbine drills and original luxator tooth instruments in extraction of medial mesial horizontal impacted wisdom teeth of mandible. Method 80 cases of young orthodontic patients with the lower anterior teeth crowded dislocation caused by medial mesial horizontal impacted wisdom teeth of mandible are screened out during 3 years from March 2009 to March 2012, and randomly di⁃vided into two groups, study group and control group of 40 cases respectively. The study group adopts high-speed turbine drill and orig⁃inal luxator tooth instrument, while the control group adopts conventional extraction equipments (tooth forceps, chisel, hammer), then re⁃cord the extraction time, the patient's intraoperative and postoperative symptoms after seven days when referral. Results The average extraction time of the study group is 15 min, while the control group 32.5 min. The average extraction time of the study group is signifi⁃cantly less than that of the control group. As for intraoperative and postoperative reaction and patients

  20. Physical characterization of soil and operational performance of agricultural machines in the deployment of forage sorghumCaracterização física do solo e desempenho operacional de máquinas agrícolas na implantação da cultura do sorgo forrageiro

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    José Guilherme Lança Rodrigues

    2011-12-01

    Full Text Available Forage sorghum can be grown in areas presenting dry and hot environmental situations where the yield of other grasses can often be uneconomical. The objective of this study was to analyze the operating performance of agricultural machines in the deployment of sorghum forage in four tillage systems, as follows: no-tillage system, disk harrow + seeding, disk harrow + two light disking + seeding, minimum tillage + seeding and four seeding different speeds, as follows: 3, 5, 6 and 9 km h-1. The study was performed under field conditions in FCA / UNESP, Botucatu County, SP, Brazil. The data were subjected to variance analysis in a simple factorial 4 x 4, and a random block design with split plots. Operational performance of the agricultural machinery, physical characteristics the soil, its water content and the yield of dry matter and green sorghum were determined. The operational performance of agricultural machines in the deployment of sorghum forage is influenced by the sowing speed and the soil tillage system used. Chisel plow was the equipment that required the highest mean traction force, mean traction and slip, as well as the lowest mean speed for the studied tillage system. Forage sorghum showed higher yields in no-tillage systems at a seeding speed of 5 km h-1.O sorgo forrageiro pode ser cultivado em áreas e situações ambientais secas e quentes, onde a produtividade de outras forrageiras pode ser normalmente antieconômica. O objetivo do trabalho foi analisar o desempenho operacional de máquinas agrícolas na implantação da cultura do sorgo forrageiro em quatro sistemas de preparo do solo: semeadura direta; gradagem pesada + semeadura; gradagem pesada + duas gradagens leves + semeadura; cultivo reduzido + semeadura e quatro velocidades de semeadura: 3, 5, 6 e 9 km h-1. O experimento foi instalado em condições de campo, na FCA/UNESP, Campus de Botucatu - SP. Os dados obtidos foram submetidos à análise de variância em esquema

  1. Força de tração e volume de solo mobilizado por haste sulcadora em semeadura direta sobre campo nativo, em função do teor de água no solo, profundidade e velocidade de operação Draft and soil loosening by knife type coulter related to soil moisture and planter's working speed and depth

    Directory of Open Access Journals (Sweden)

    Carla T. C. Cepik

    2005-08-01

    Full Text Available A semeadura direta é um sistema de manejo eficiente em termos de conservação do solo e da água, economia de energia e capacidade operacional dos conjuntos mecanizados. No entanto, em áreas onde existem pecuária e produção de grãos, ou onde o solo é trafegado e trabalhado em condições inadequadas, pode ocorrer compactação do solo nas camadas superficiais. Mesmo compactadas, essas camadas não necessitariam ser descompactadas ou revolvidas, se boa germinação e desenvolvimento da cultura fossem alcançados apenas com a mobilização efetuada pelos sulcadores da semeadora. Os objetivos deste estudo foram determinar a força de tração demandada e o volume de solo mobilizado pelas hastes sulcadoras de adubo, além da patinagem do trator, em diferentes estados de consistência de um Argissolo, em semeadura direta sobre campo nativo dessecado. Houve aumento na demanda de tração com o aumento da profundidade de atuação da haste, e sua magnitude dependeu do estado de consistência do solo. O aumento da velocidade não influenciou na força de tração na haste em solos seco e úmido, porém, na condição de friabilidade, essa foi maior. O volume de solo mobilizado pelo sulcador foi maior em solo seco e a 12 cm de profundidade. Nos estados de consistência seco e friável e na maior profundidade testada, verificou-se a necessidade de acionamento da TDA do trator para obtenção de níveis aceitáveis de patinagem.Direct drilling or no tillage systems are among the most successful agricultural alternatives regarding soil and water conservation, energy economy and operational capacity of machinery. Some areas where cattle raising and grain production share the same grounds, or where soils are trafficked in moist conditions they may show compaction of the upper layers. Compacted soil areas may not need to be chiseled or plowed, if seed germination and good growing standards are reached by the initial soil conditioning solely by planter

  2. COMPONENTES BIÓTICOS DE UM CAMPO DE PESQUISA SOB QUATRO SISTEMAS DE MANEJO DE SOLO BIOTIC COMPONENTS OF ONE RESEARCH SITE UNDER FOUR SOIL MANAGEMENT SYSTEMS

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    Renato Sérgio Mota dos Santos

    2007-09-01

    Full Text Available

    A matéria orgânica foi estudada em latossolo roxo eutrófico, sob vegetação de cerrado, em Santa Helena (GO, Brasil, em região tradicional em plantio direto, em locais onde estavam sendo realizados quatro sistemas de manejo durante dois anos: plantio direto (PD, aração profunda (AP, grade aradora (GA e escarificação profunda (EP. As ervas daninhas observadas na área produziram 2.369, 124, 243, 640 kg/ha de matéria seca no PD, AP, GA e EP, respectivamente, colhidos 30 dias após o preparo do solo. A matéria orgânica concentrou-se na camada arável do solo onde se realizou o plantio direto (PD e dispersou nas camadas mais profundas onde se utilizou a aração profunda (AP. A escarificação profunda (EP comportou-se semelhantemente ao plantio direto (PD. Os valores de pH mais baixos foram verificados na camada arável do solo sob manejo do plantio direto. Maior número de fungos e bactérias foi observado nas áreas de plantio direto (PD, bem como de propágulos de Rhizoctonia solani e Fuzariun solani.

    PALAVRAS-CHAVE: Matéria orgânica; pH; patógenos do solo; plantio direto; aração profunda; escarificação; gradagem; aivecagem.

    Organic matter was studied in a savanna oxisol during two years, in Santa Helena, state of Goiás, Brazil, a traditional no-till management area, in which four soil management systems were developed: no-tillage (PD, deep moldboard plowing (AP, shallow harrow plowing (GA and deep stirring, using a chiseling plower (EP. The dry matter from weed plants observed in the area produced 2369, 124, 243, 640 kg/ha in PD, AP, GA and EP, about 30 days after soil management, respectively. The organic matter was concentrated in the arable soil layer in areas where no-till management was adopted (PD and was

  3. Overland flow connectivity in olive orchard plots with cover crops and conventional tillage, and under different rainfall scenarios

    Science.gov (United States)

    López-Vicente, Manuel; García-Ruiz, Roberto; Guzmán, Gema; Vicente-Vicente, José Luis; Gómez, José Alfonso

    2016-04-01

    The study of overland flow connectivity (QC) allows understanding the redistribution dynamics of runoff and soil components as an emergent property of the spatio-temporal interactions of hydrological and geomorphic processes. However, very few studies have dealt with runoff connectivity in olive orchards. In this study we simulated QC in four olive orchard plots, located on the Santa Marta farm (37° 20' 33.6" N, 6° 13' 44" W), in Seville province (Andalusia) in SW Spain. The olive plantation was established in 1985 with trees planted at 8 m x 6 m. Each bounded plot is 8 m wide (between 2 tree lines) and 60 m long (total area of 480 m2), laid out with the longest dimension parallel to the maximum slope and to the tree lines. The slope is uniform, with an average steepness of 11%. Two plots (P2 and P4) were devoted to conventional tillage (CT) consisting of regular chisel plow passes depending on weed growth. Another set of two plots had two types of cover crops (CC) in the inter tree rows (the area outside the vertical olive canopy projection): uniform CC of Lolium multiflorum (P3) and a mixture of L. rigidum and L. multiflorum together with other species (P5). The tree rows were treated with herbicide to keep bare soil. We selected the Index of runoff and sediment Connectivity (IC) of Borselli et al. (2008) to simulate three rainfall scenarios: i) low rainfall intensity (Sc-LowInt) and using the MD flow accumulation algorithm; ii) moderate rainfall intensity (Sc-ModInt) and using MD8; and iii) high rainfall intensity (Sc-HighInt) and using D8. After analysing the values of rainfall intensity during two hydrological years (Oct'09-Sep'10 and Oct'10-Sep'11) we associated the three scenarios with the followings months: Sc-LowInt during the period Jan-Mar, that summarizes 42% of all annual rainfall events; Sc-ModInt during Oct-Nov and Apr-May (32% of all events); and Sc-HighInt during the period Jun-Sep and in December (26% of all events). Instead of using the C

  4. Characterization of Finnish Building materials under salt frost artificial ageing

    Science.gov (United States)

    Luodes, Nike M.; Torppa, Akseli; Pirinen, Heikki; Bellopede, Rossana; Marini, Paola

    2016-04-01

    Under a national project co financed by the Confederation of Finnish Construction Industries RT (CFCI), the Finnish Natural Stone Association and the Geological Survey of Finland (GTK), and thanks to the cooperation with the Polytechnic of Turin a comprehensive number of Finnish natural stones has been tested according to SFS EN standards for national CE marking and according to non standardized methods for research purposes. The aim was to evaluate the effects of combined salt and frost weathering caused by de-icing salts and to research a possible correlation between laboratory's accelerated decay and site weathering. The materials tested (60 stones in total) are mainly silicate rocks showing good resistance to the weathering. Results have been affected in some cases by uncertainties connected to the variation of material quality. Some materials have been from new quarries and variation of their properties has been higher than the effects of artificial weathering. Material sampled from crop presented higher weathering level and the additional artificial weathering has induced small variations. Results have shown that material weathering has been better represented by variation of flexural strength compared to uniaxial compressive strength. The most probable reason has been that small changes of planarity and perpendicularity had greater effects on the compressive strength than variations by weathering. Fifteen representative typologies of natural stones have been tested with non standardized methodologies to study the changes of the material and finding a possible correlation with methods used on site. Schmidt rebound test and Ultra Pulse Velocity (UPV) have been used on site to assess the durability of stone on construction. Materials tested in laboratory have shown less variation between rebounds compared to site tests, this can be because of a more controlled environment and saw cut surface instead of rocky or chiselled ones. Laboratory tests showed an average

  5. U-series dating of pillow rim glass from recent volcanism at an Axial Volcanic Ridge

    Science.gov (United States)

    Thomas, L. E.; van Calsteren, P. W.; Jc024 Shipboard Party

    2010-12-01

    Visual observations using camera systems on the tethered ROV Isis deployed during the 2008 JC024 cruise to the Mid Atlantic Ridge at 45°N showed1 numerous monogenetic volcanoes that are essentially piles of lava pillows. The pillows are usually ˜1m diameter and >2m long and form mounds with average dimensions around 300m diameter, ˜150m altitude, and 0.005km3 volume. Small protrusions, 10-50cm long, which are numerous on pillows appear to be the youngest regions, were sampled using the pincers on the hydraulic arms of Isis, and returned to the surface. On the surface, any glass crust on the pillow protrusions was chiselled off using clean tools and double bagged in polythene. In the laboratory a portion of the glass was crushed in a jeweller’s roller mill and sieved using stainless steel sieves to obtain a sufficient amount of the fraction 0.125-0.250mm for hand picking, using a binocular microscope with the glass submerged in a mix of water and iso-propyl alcohol. The samples were subsequently leached using the procedure of Standish & Sims2. Samples were spiked with a mixed 229Th-236U spike and the U, Th and Ra fractions were separated and purified using standard chemistry methods. U and Th isotope ratios were determined using a Nu Instruments MC-ICPMS and Ra isotope ratios were determined using a MAT-262-RPQII TIMS instrument. The U-series data were evaluated using a MathCad program based on published4,5,6 equations. The data can be successfully modelled by assuming the ‘accepted’ mantle upwelling rate for the region of 11mm.y-1. The U-Th characteristics are mostly derived during ‘porous flow’ magma upwelling in the garnet stability zone, ranging to a depth of 60km with incipient melting starting at 70km. Above 60km depth the melt fraction will be >3% and the mantle mineralogy devoid of phases that fractionate U-Th significantly. Moreover, at melt fractions >3%, channel flow will be dominant and magma will transit to eruption on time-scales that are

  6. Land use and land management effects on soil organic carbon stock in Mediterranean agricultural areas (Southern Spain)

    Science.gov (United States)

    Parras-Alcántara, Luis; Lozano-García, Beatriz

    2014-05-01

    INTRODUCTION Soils play a key role in the carbon geochemical cycle. Agriculture contributes to carbon sequestration through photosynthesis and the incorporation of carbon into carbohydrates. Soil management is one of the best tools for climate change mitigation. Small increases or decreases in soil carbon content due to changes in land use or management practices, may result in a significant net exchange of carbon between the soil carbon pool and the atmosphere. In the last decades arable crops (AC) have been transformed into olive grove cultivations (OG) or vineyards (V) in Mediterranean areas. A field study was conducted to determine long-term effects of land use change (LUC) (AC by OG and V) on soil organic carbon (SOC), total nitrogen (TN), C:N ratio and their stratification in Calcic-Chromic Luvisols (LVcc/cr) in Mediterranean conditions. MATERIAL AND METHODS An unirrigated farm in Montilla-Moriles (Córdoba, Spain) cultivated under conventional tillage (animal power with lightweight reversible plows and non-mineral fertilization or pesticides) was selected for study in 1965. In 1966, the farm was divided into three plots with three different uses (AC, OG and V). The preliminary analyses were realized in 1965 for AC (AC1), and the second analyses were realized in 2011 for AC (AC2 - winter crop rotation with annual wheat and barley, receiving mineral fertilization or pesticides), OG (annual passes with disk harrow and cultivator in the spring, followed by a tine harrow in the summer receiving mineral fertilization and weed control with residual herbicides), and V (with three or five chisel passes a year from early spring to early autumn with mineral fertilization or pesticides.). In all cases (AC1, AC2, OG and V) were collected soil entire profiles. Soil properties determined were: soil particle size, bulk density, SOC, TN, C:N ratio, stocks and SRs. The statistical significance of the differences in the variables between land use practices was tested using the

  7. Dacriocistorrinostomia endoscópica Endoscopic dacryocystrhinostomy

    Directory of Open Access Journals (Sweden)

    Bernardo Cunha Araujo Filho

    2005-12-01

    Full Text Available A dacricistorrinostomia (DCR endoscópica é uma técnica aceita e bem estabelecida no tratamento de obstruções distais da via lacrimal tornando seu domínio pelos otorrinolaringologistas indispensável. OBJETIVO: O objetivo desse artigo é apresentar a experiência em DCR endoscópica da Divisão de Clínica Otorrinolaringológica do Hospital das Clínicas da USP, comparando com os resultados na literatura. FORMA DE ESTUDO: clínico retrospectivo. MATERIAL E MÉTODO: Foram analisados prontuários de 17 pacientes (17 olhos, submetidos à DCR endoscópica, no período entre abril de 2001 e julho de 2004, na qual foram avaliados com relação a sexo, idade, etiologia, quadro clínico, técnica cirúrgica utilizada, uso de sonda de silicone e tempo de permanência, seguimento e as complicações observadas. RESULTADOS: Oito homens e nove mulheres, com idade variando de 29 a 79 (média: 42,64 13,1 apresentaram um seguimento médio de 15 meses. A causa principal da obstrução foi idiopática (58,8%. A epífora foi a queixa predominante. Em 6 pacientes utilizamos instrumentos motorizados, em um caso utilizamos o Laser Yag e no restante, chisel e martelo. Em todos os casos utilizamos sondas de silicone, por período médio de 7,9 semanas e o sucesso da técnica endonasal foi de 82,3%. CONCLUSÃO: A técnica endoscópica se mostrou uma técnica segura, com uma série de vantagens em relação à técnica externa e, desta forma, oftalmologistas e otorrinolaringologistas devem trabalhar em harmonia para oferecer maiores benefícios aos seus pacientes.Endonasal endoscopic dacryocystorhinostomy (EN-DCR is now a well-established procedure to relieve nasolacrimal duct obstruction, becoming its domain for the ENT surgeons indispensable. AIM: The aim of the present study is to report the experience of the Otorhinolaryngology Department of the University of São Paulo Medical School in the management of the obstruction of the drainage of the nasolacrimal

  8. Temperatura do solo em função do preparo do solo e do manejo da cobertura de inverno Soil temperature as affected by soil tillage and management of winter cover crops

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Angeli Furlani

    2008-02-01

    Full Text Available Com o objetivo de avaliar o efeito do preparo do solo e do manejo da cobertura de inverno (consórcio aveia-preta + nabo forrageiro sobre a temperatura do solo, realizou-se um experimento em um Nitossolo em Botucatu-SP no outono/inverno de 2000. Utilizou-se um delineamento em blocos casualizados em esquema fatorial 3 x 3 (três preparos e três manejos. O preparo do solo constou de: preparo convencional, preparo conservacionista com escarificação e plantio direto, e o manejo da cobertura: consórcio dessecado, rolado e triturado. Foram avaliados a temperatura do solo (termopares a 5 cm de profundidade, de hora em hora, aos 7, 14, 30, 45 e 60 dias após a emergência das plantas do consórcio; o teor de água do solo na profundidade de 10 cm, nas mesmas épocas; e a cobertura do solo (massa seca e índice de cobertura, imediatamente após aplicação dos tratamentos. O sistema plantio direto apresentou temperaturas do solo menores que as do preparo convencional, até o 14º dia após emergência (DAE das plantas. A partir do 30° DAE das plantas, a temperatura não foi mais influenciada pelos tratamentos, devido à cobertura do consórcio e ocorrência de boa disponibilidade de água no solo. Os manejos da cobertura com rolo-faca, triturador e herbicida não influenciaram a temperatura do solo. A temperatura do solo não interferiu no crescimento e desenvolvimento das culturas de cobertura.To evaluate the effect of soil tillage and management of winter cover crops (black oat + radish intercrop on the soil temperature, an experiment was conducted in a Nitossol (Alfisol in Botucatu, state of São Paulo, Brazil, in the 2000 fall/winter season. A design in randomized blocks was used in a 3 x 3 factorial scheme (three tillage and three cover crop managements. Soil tillage consisted of: conventional tillage, conservation tillage with chiseling, and no-tillage. The cover crops managements included plant killing with post-emergence herbicide, rolling

  9. 三种方法拔除近中中位水平阻生牙的效果比较%Comparison of three methods for extraction of near the median level of impacted tootheffect

    Institute of Scientific and Technical Information of China (English)

    毛全军

    2015-01-01

    Objective Analysis of advantages and disadvantages of 3 methods in the extraction of mandibular near the median level of impacted tooth. Methods 150 patients with 2013-2014 were se⁃lected in the mesial median level resistance,were randomly divided into 3 groups (n=50).A group us⁃ing the traditional split crown extractionmethod, and group B with three section extraction method,and group C with T-shape type of crown truncation method of extraction.Comparison of 3 methods of ex⁃tracting time, root cutting phenomenon appeared during the operation,swelling and pain, postopera⁃tive,sensitive patients with second molar surgery. Results 3 methods of extracting time,group C was the lowest,followed by group B, group A for the longest time,the difference was statistically signifi⁃cant (P0.05). Conclusion T-shape of crown truncation method of extraction and three section extraction method of clinical effect is better than that of traditional chisel in extraction methods.T-shape of crown trunca⁃tion method of extraction can shorten the operation time, worthy of clinical application.%目的:探讨3种方法在拔除下颌近中中位水平阻生牙的优缺点。方法:选取2013年1月-2014年3月我科收治的下颌近中中位水平阻生牙患者150例,随机均分为3组(n=50)。A组采用传统劈冠拔除方法,B组采用三段式横断拔除方法,C组采用“T”形截冠拔除方法。比较3种拔除方法所用时间,术中出现断根现象,术后疼痛、肿胀,第二磨牙术后出现敏感的患者。结果:3种拔除方法所用时间,C组最少,B组其次,A组时间最长,差异有统计学意义(P<0.05),B、C两组术中出现断根现象,术后疼痛、肿胀,第二磨牙术后出现敏感的发生率少于A组,差异有统计学意义(P<0.05),但是B、C两组间的数据差异没有统计学意义(P>0.05)。结论“:T”形截冠拔除方法和三段式横断拔除方法临床效果

  10. Demanda energética e eficiência da distribuição de sementes de milho sob variação de velocidade e condição de solo Seeder energetic demand and distribution efficiency of corn seeds under speed variation and soil condition

    Directory of Open Access Journals (Sweden)

    Denise Mahl

    2004-04-01

    carried out under no tillage system during those last five years, soil prepared with chisel plow 18 months before seeding. Parameters of traction force, power, fuel consumption, effective field capacity, longitudinal distribution of plants, variation coefficient, precision index and initial plants stand were appraised. The results showed that increasing the speed of 4.4 to 8.1 km h-1, increases 86% the operational capacity of the group tractor/seeder, increasing 96% the power demand in the traction bar and reduction of 26% in the operational fuel consumption. The fastest speed (8.1 km h-1 provided a smaller percentile of normal spacing and an increasing in the percentile of multiple and fail spacing, larger variation coefficient and worse precision index. The speed variation didn't interfere in the plant stand.

  11. Parâmetros solo-máquina em função de doses de resíduos vegetais e profundidades de deposição de adubo em semeadura direta Parameters of soil-machine in function of the amount of cover residues and different fertilizer deposition depths in direct drilling

    Directory of Open Access Journals (Sweden)

    Karina M. Kamimura

    2009-09-01

    , sub-plots were two working depth of the driller chisel-type furrow opener, and two traffic conditions (combine and tractor wheel traffic.The physical characteristics of the soil were influenced by the traffic tracks. The whole tractor-drill was influenced by the depths of fertilizer shanks and traffic of traffic tracks and combine.

  12. Consumo energético, eficiencia de campo y cobertura vegetal en labranza-siembra de maíz en el Valle del Cauca, Colombia

    Directory of Open Access Journals (Sweden)

    Herrera G Oscar A.

    2005-03-01

    Full Text Available En el Centro de Investigaciones Palmira de la Corporación Colombiana de Investigación Agropecuaria, Corpoica, se realizó un estudio de auditoría energética en cuatro métodos de labranza-siembra (vertisol de maíz en rotación con algodón. El mayor consumo de energía fósil correspondió a labranza convencional (LC, en la cual más del 70% se invirtió en las labores de labranza primaria y secundaria, seguida de cincel vibratorio (CV con un 65% y de mulch-tiller (MT con 54%; siembra directa (SD sólo empleó combustible fósil en la operación de desbroce de la soca y en la siembra; LC requirió casi 4 veces más energía que SD, CV casi 3 veces más y MT 2.7 veces más; el costo del combustible estuvo en igual proporción, lo mismo que el costo ambiental; en LC, MT y CV el primer pase del implemento de labranza consumió entre 1.5 y 3 veces más energía que el segundo y tercer pases, en suelos tenaces como los vertisoles del CI Palmira. Los altos valores de eficiencia de campo en LC contrastaron con el elevado consumo energético, en comparación con SD, y éste mostró diferencias notorias con respecto a los demás métodos de labranza-siembra en lo relacionado con la conservación de la cobertura vegetal del suelo. ABSTRACT Energy consumption, field efficiency and on ground vegetal cover in corn till-planting systems on Valle del Cauca, Colombia. Corn-cotton energy audit in four tillage-planting systems was carried out at the Colombian Corporation of Agricultural Research Center branch Palmira. The highest consumption of fossil energy corresponded to conventional tillage (LC, in which more than 70% of this consumption corresponded to primary and secondary tillage, followed by vibratory chisel (CV with 65% and mulch-tiller (MT with 54%, whereas no-till planting (SD observed the lowest energy consumption, because it suppressed itself primary and secondary tillage and only used fossil fuel to prepare the soca of the previous

  13. Manejo do solo e da adubação nitrogenada na cultura de feijão de inverno e irrigado Soil management and nitrogen fertilization on winter irrigated common bean

    Directory of Open Access Journals (Sweden)

    Flávio Ferreira da Silva Binotti

    2007-01-01

    of 2002, 2003 and 2004. A randomized block design was used, with 24 treatments, constituted by three soil management system (heavy disk + leveling disk, chisel ploughing + leveling disk and no tillage and eight stadia of nitrogen application (control without N application, at sowing - S, V3 stadium, V4 stadium, 1/2 S + 1/2 V3, 1/2 S + 1/2 V4, 1/2 V3 + 1/2 V4 and 1/3 S + 1/3 V3 + 1/3 V4, with 4 replications. As conclusion, for the three years of cropping, in only one of them, the no till system provided larger yield in the winter common bean irrigated by aspersion in relation to the conventional soil management. The stadia of nitrogen application did not provide differences in the yield of the bean plant. The nitrogen fertilization provided, on average of three crops, an increase of 62% in the yield of the common bean plant as compared with the control without N.

  14. Evolution of physical properties of soils according to tillage systems on annual crops/ Evolução de propriedades físicas do solo em função dos sistemas de manejo em culturas anuais

    Directory of Open Access Journals (Sweden)

    Rogério R. M. Ferreira

    2006-06-01

    Full Text Available Soil management must keep the soil physical properties next to the original conditions in natural systems to assure the sustainability of agricultural systems. This review synthesizes the effects of conventional tillage, minimum tillage and no-tillage systems of annual crops, on soil physical properties as bulk density, porosity, soil resistance to root penetration, infiltration speed, hydraulic conductivity,compressibility, organic matter level, soil aggregate size and stability. No-tillage presents advantages on organic matter level, size and stability of aggregates, compressibility and hydraulic conductivity but has limitations on bulk density and resistance to root penetration. Minimum tillage with chisel plow is specially efficient in relation to infiltration speed and hydraulic conductivity, and intermediate between conventional and no-tillage in other aspects. Conventional tillage with total pulverization of soil surface,mainly on tropical conditions, presents the less favorable scores on soil physical properties, close to minimum tillage and no-till only in few circumstances, and frequently the most different from the natural conditions. The conservation systems by their side, despite of similarities in some aspects with natural conditions, are not able to reproduce the conditions of natural forests, savannas or natural pastures, but are in the sustainability direction.Para assegurar a sustentabilidade do sistema produtivo, o manejo do solo deve manter as propriedades físicas do solo o mais próximo das condições originais em que este se encontrava na natureza. Esta revisão sintetiza os efeitos de três sistemas de manejo de solo (convencional, mínimo e direto em culturas anuais sobre as propriedades físicas do solo como densidade, porosidade, resistência à penetração, velocidade de infiltração, condutividade hidráulica, compressibilidade, nível de matéria orgânica, tamanho e estabilidade de agregados. O plantio direto

  15. Morfologia de agregados do solo avaliada por meio de análise de imagens Morphology of soil aggregates evaluated by images analysis

    Directory of Open Access Journals (Sweden)

    N. Olszevski

    2004-10-01

    deterioration of soil physical properties, mainly due to modifications in the soil structure pattern. Once the structural changes could affect the morphology aggregates in different ways, the search for new methods of studying soil macro-morphological characteristics must be prioritized to allow the observation of modified characteristics in cultivated soils. Therefore, this study was carried out to adapt and test a digital method for a qualitative macro-morphological analysis of soil aggregates of Rodhic Haplustox in samples taken in 1998, aiming to detect morphological modifications caused by human activities. From an original set of eleven, five replicated treatments were selected: no till, cinzel plow, heavy disk harrow, disk plow and chisel plow, carried out annually. The shape of the different soil aggregates was from images obtained using a scanner (HP 6100C with 1200 dpi optical resolution which were then processed by the computer program UTHSCSA Image Tool. This program furnishes values of different aggregate indexes: roundness, compactness and lengthiness. The roundness index depends on the perimeter measurement (external roughness and the compactness and lengthiness indexes depend on the measurement of the length of the longest axle (long edges. Generally, the management systems used during three consecutive years did not modify the aggregate morphology of the clayey Rodhic Haplustox for the analyzed variables. Image analysis sensitively detected alterations in soil aggregate morphology promising considerable usefulness as a novel tool for on soil structure studies.

  16. The CHARISMA project in ATOMKI

    International Nuclear Information System (INIS)

    Analysis (ERDA) and Scanning Transmission Ion Tomography (STIM). The expected fields of study are: a) materials alterations on samples (origin, products and mechanisms); b) provenance studies; c) characterization of micro-details of altered or unaltered materials e.g. to prevent further damage; d) studying of the manufacturing techniques for a contribution to art-historical studies; e) characterisation of the artwork conservation state or the effectiveness of a conservation treatment. In 2010 seven projects were carried out within the CHARISMA TNA service in ATOMKI. The guest researchers arrived from Bulgaria, Germany, Greece, Finland and Romania. The investigated artefacts included nephrite axes and chisels from the Neolithic era, bronze and copper objects as well as gem stones (joint access project with the Budapest Neutron Centre) from the Bronze Age, antique pottery, decorative metal objects from the Middle Ages and pre-modern glass. In all cases major, minor and trace elements were quantified. In most of the cases the use of the ion microprobe was indispensable due to the heterogeneity and microstructure of the samples. The publication of the results is under way.

  17. Gneisses (Serizzi and Beole) of the Verbano-Cusio-Ossola district (Piedmont, Northern Italy): possible candidates for the designation of "Global Heritage Stone province"

    Science.gov (United States)

    Antonella Dino, Giovanna; Borghi, Alessandro; Cavallo, Alessandro; Primavori, Piero

    2016-04-01

    The Verbano-Cusio-Ossola quarrying district (Piedmont, northern Italy) produces many different ornamental stones (granites, gneisses, marbles): two really important categories are represented by Serizzo and Beola gneisses. Several varieties of Serizzo and Beola crop out in the upper and middle Ossola Valley: Serizzo derives from the Antigorio, Monte Leone and Monte Rosa Penninic Units, whereas Beola from the Monte Leone, Orselina-Moncucco-Isorno and Monte Rosa Penninic Units, as well from the Fobello-Rimella schists (Austroalpine). The Serizzo, represented by a group of foliated granitoid orthogneisses (Serizzo Antigorio, Serizzo Formazza, Serizzo Sempione and Serizzo Monte Rosa varieties), is probably the most important and extensively exploited ornamental stones from the VCO province (about 70% of the VCO stone production). The quarries are mostly concentrated in the Antigorio and Formazza valleys, where the Antigorio nappe has a sub-horizontal attitude and reaches its greatest thickness (up to 1000 m). This stone was largely used to produce columns since the end of XV century (e.g. the old Ospedale Maggiore in Milano, now University of Milano) and later on it was replaced with granites. It was also used in the building structure of the Duomo di Milano, for the plinth and the piers. Nowadays, thanks to its good wear resistance and low cost, it is mainly used in polished slabs for paving: a recent application is the Frankfurt airport floor. Beola is the name of a group of heterogeneous orthogneisses with mylonitic foliation and strong mineralogical lineation (Beola Grigia, Bianca, Ghiandonata, Striata varieties), easy to split into thin slabs with hammer and chisel, occurring in the middle Ossola Valley, between Vogogna and Montecrestese. The quarries of Beola are probably the oldest of the Ossola Valley, although the precise period in which the stone started to be exported is unknown. The Beola trade probably started at the end of the XIII century, with the

  18. Corsica and Sardinia

    Science.gov (United States)

    2002-01-01

    Rich in antiquities and picturesque landscapes, the island provinces of Corsica, France, (top) and Sardinia, Italy, (bottom) have captured the imaginations of historians and poets alike for centuries. Corsica, crowned with snow-capped mountains, jeweled with shimmering lakes, and cloaked in misty emerald forests, is situated in the sapphire blue Mediterranean Sea southeast of mainland France. The island enjoys a relatively warm climate consisting of hot, dry summers full of sunshine, and mild winters that rarely dip below 0oC (32oF). In this scene, Corsica is the smaller island to the north. The island has almost 1,700 hills and mountains, ranging from 300 to over 2,700 meters in height. The tallest of these peaks is the snow-capped Monte Cinto toward the northern end of the island. Coursing throughout the island is an extensive network of rivers, carved into Corsica's granite face by snowmelt and rainwater runoff. The Corsican Cape sits on the island's northern finger; its eastern slope is somewhat hilly. There are quite a few agricultural fields and vineyards visible as the light green swath to the south all along the eastern shore. Along the southern shore are the dazzling cliffs of Bonifacio. Moving up the west coast in the state of Ajaccio we see a jagged, chiseled water front, reminiscent of the famous fjords of Norway. There are four large gulfs and many smaller rocky inlets sculpted into Corsica's west coast. Moving soutward, they are the Gulfs of Porto, Sagone, Ajaccio, and Valinco. The larger island to the south--across the Strait of Bonifacio--is Sardinia, Italy, one the earliest populated lands of Europe. Some ancient artifacts date human populations there as old as 6000 B.C. Around 1500 B.C., another group of settlers arrived on the island (historians don't know where they came from) and spread quickly across the island. Known as the Nuragic people, these settlers built almost 30,000 circular fortresses--called 'nuraghe'-- around the island; each

  19. Clinical application and evaluation of anterior interlocking plate internal fixation in ankle arthrodesis%前路锁定钢板内固定在踝关节融合术中的应用及初步评价

    Institute of Scientific and Technical Information of China (English)

    余剑; 赵建宁; 郭亭; 蔡滕

    2012-01-01

    目的 评价前路锁定钢板内固定在踝关节融合术中的临床应用及疗效.方法 收治各类踝关节终末期病变21例,踝前部皮肤、软组织条件均良好.采用踝关节前正中手术入路暴露踝关节前方,凿除踝关节软骨面,摆正踝关节体位,取肱骨近端或胫骨近端锁定钢板于踝关节前方行内固定.结果 所有患者随访6~47个月,X线片示踝关节全部融合.按AOFAS踝-后足功能评价系统,本组优15例,良6例.结论 前方入路锁定钢板内固定技术具有操作简单、暴露充分、避免额外截骨、固定牢靠等优点,融合率高,矫形力强,并发症少,能够较好恢复和维持躁关节的正常外形,尤其适合于合并畸形、关节周围骨缺损及骨质疏松等各类复杂踝关节终末期病变.%Objective To evaluate the the clinical application and efficacy of anterior approach plus internal fixation with interlocking plate in ankle arthrodesis. Methods From January 2007 to February 2011, twenty-one patients with end-stage disease of ankle joint were treated, and the skin and soft tissue conditions before the ankle were fine. All received operations including following steps: exposed the ankle with the anterior approach,chiseled to the ankle joint cartilage, straightened position of the ankle, made internal fixation with interlocking plate to ankle. Results All patients were followed up for 6 to 47 months, X-ray showed that full integration of ankle. According to the AOFAS assessment of ankle-foot functions, in this groups, 15 cases were excellent,6 cases were good. Conclusion The anterior approach plus internal fixation with interlocking plate in ankle arthrodesis have the advantages of simple operating, completely exposing, rigid fixing, avoiding osteotomy, which leads to high rate of fusion and correction and low rate of complication. In conclusion, this technique could correct deformity of ankle and maintain the stability excellently, and so it is

  20. Some aspects of influence of radioactive poluution on vegetative communities of Apsheron

    International Nuclear Information System (INIS)

    Full text: Absheron represents unique natural ecological reserve where there is a wide spectrum of various kinds of plants. A variety of vegetative kinds is determined first of all by ecological conditions in which grow, conditions in which evolution proceeds and disappear separate kinds of plants. Influence of natural, and stressful factors, such as the strong drought, soil salinity, big solar radiation and gale-force winds, for many centuries have generated on Apsheron vegetative communities, with high stability against various stresses. And uniqueness of flora Apsheron consists in the big biovariety of flora and occurrence of vegetative communities such as xerophits, mezophits, gigrophits and giarophits. They meet both in desert, and in mountain heights and in a coastal zone of Caspian sea of Apsheron. On a specific variety makes about 22 percent from the common number kinds of plants growing in Azerbaijan. Among them there are rare, disappearing, relic kinds and endemics. However progressing deterioration of ecological situation as over all Azerbaijan, and in particular on Apsheron, caused by climatic cataclysms, anthropogenous factors, accumulation of radionuclids, heavy metals, erosion, salinity etc. Occurrence polluted with radionuclids zones on Apsheron, basically are connected to development of hydrocarbonic stocks (petroleum and gas) and, as consequence, an output on a surface radioactive isotopes, chisel waters from oil wells, a lining of gas-oil pipelines. As have shown our researches, on Apsheron peninsula the most polluted territories which radioactive background reaches from 6-400 μR/h are revealed. It is most radioactive the polluted sites were found out in territories with a rich network of the oil-extracting and oil refining enterprises and in territory of petrochemical factories. In vegetative and soil samples activity of such natural radionuclids as E 40, An 228, Pb 214, Tl 208 were 38,3 - 2089; 17,16 - 756,9; 8,7 - 4793; 3,19 - 263 Bq

  1. Effects of tillage and crop residue management on soil respiration and its mechanism%耕作方式与秸秆还田对土壤呼吸的影响及机理

    Institute of Scientific and Technical Information of China (English)

    赵亚丽; 薛志伟; 郭海斌; 穆心愿; 李潮海

    2014-01-01

    In Huang-Huai-Hai area in China, winter wheat (Triticum aestivum)/summer maize (Zea mays) rotation is the dominant two-crop-per-year cropping system. Crop residue removal and subsoil compaction have become limiting factors for yield improvement in the area. Tillage and crop residue retained are two effective ways to improve soil properties and increase crop yield. Soil tillage and crop residue retained can reduce soil bulk density, improve water storage and aeration in the soil, increase soil microorganism and enzyme activities, improve soil biological properties, thus promote plant root growth and increase crop production. However, studies in the past mainly focused on the effects of single tillage or single crop residue retained on soil respiration. There is a need currently for research in the effects of tillage, crop residue retained and their interaction on soil respiration under the two-crop-per-year cropping system. A two-year field study from 2010 to 2012 was conducted to determine effects of tillage practice and crop residue management on soil respiration, soil temperature, soil water content, soil compaction, soil organic carbon content, dry matter accumulation of plant and root in the wheat-corn double crop cropping system. The study was conducted at the Wen County Experimental Station, Henan, China. The experiment was arranged in a split-plot design with three replications. Tillage practice and crop residue management were two factors of interest. The tillage treatment was randomly assigned to main plots and crop residue treatment was randomly assigned to sub-plots. The tillage practice treatments were: moldboard plough (MP) to a maximum depth of 15 cm, deep moldboard plough (DMP) to a maximum depth of 30 cm, and chisel plough (CP) to a maximum depth of 30 cm. All three tillage treatments were implemented after corn harvested in October of 2010 and 2011. In addition to different plough treatments, all plots were disc harrowed before wheat planting

  2. ATIVIDADE DO ALUMÍNIO NA SOLUÇÃO DO SOLO DE UM LATOSSOLO VERMELHO DISTRÓFICO SUBMETIDO AO MANEJO DO SOLO E DE CULTURAS

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    Silvio Tulio Spera

    2014-09-01

    concerning the percentage of activity and forms of toxic Al in two soil layers situated among 0 to 20 cm. The samples were from experiment conducted in Passo Fundo, RS, in a Typic Haplustox, after more than two decades of cropping, without limestone application. The experimental design was randomized block, in subplots scheme. The treatments consisted of: no-tillage (PD, minimum cultivation with chisel plow (PM and conventional plowing with disk plow (PC. These were combined with crop rotations: wheat-soybean (R1; wheat- soybean/common vetch-sorghum (R2 and wheat-soybean/common vetch-sorghum/white oats-soybean (R3, to assess the effect of these rotations interactions with the soil management type on the grains yield (RG, in the crops dry mass(MS and chemical attributes of soil solution concerning the percentage on activity and forms of Al toxic, in layers of 0 to 6.7 cm and 6.8 to 20 cm. There were no correlations between the RG and the MS and the soil attributes assessed, in both layers, even when differences in levels of chemical and physical constraint between the layers. Chemical attributes of soil solution were not influenced by the  studied factors interaction, being slightly influenced by crop rotation. The PD provided the greatest values of dissolved organic carbon and lowest level and Al activity in soil solution. Keywords: soil acidity; no-till, soil plowing, soil chemistry. DOI: http://dx.doi.org/10.14583/2318-7670.v02n03a01

  3. Further Development Research and Countermeasures for the Tourism Resource of the National Geological and Ecological Park in Zhangzhou%漳州国家地质生态公园旅游资源的深度开发研究与对策

    Institute of Scientific and Technical Information of China (English)

    张倩倩

    2013-01-01

    After several field visits and data col ection, found the district retains the style typical of the Tertiary central volcanic eruption weathering and erosion of structural features and the topography of the late landscape. Mainly in four volcanic remains rare in the world represented, that is, columnar basalt, ancient crater, volcanic vents beaded base and basalt watermelon rind structure. This is a natural volcanic geology museum, with a high ornamental, popular and interesting. However, the concept of local tourism and weak environmental protection measures are not avant-garde and so many reasons that could have been set off in the sky, blue sea, sandy beaches, green forest into a beautiful landscape elements of these are not given to use in addition. Chisel hand here, the transformation in the design of the overal land use concept of "one, three zones, five garden"approach to the surrounding open to expansion. Ful use of existing natural beauty,embracing the green, close to nature, the use of advanced design concepts, create a pleasant and with nature, to form the leisure, tourism, entertainment, exchange of best green space. To the unique geological formations and land more harmonious growth, and ultimately meet the people back to nature, feel the natural desire for the infinite. To meet the beautiful gift of human love of nature at the same time led to the further development of the local economy can be described as a double benefit! Attempts to reach minimize adverse interference and damage to the natural human activity, to a certain extent promote the harmonious coexistence of man and nature.%经过数次的实地考察与资料收集,发现区内保留了典型的第三纪中心式火山喷发构造形迹和后期风化侵蚀的地形地貌景观。主要以四种世界罕见的火山地质遗迹为代表,即柱状玄武岩、古火山口、串珠状的火山喷气口群和玄武岩的西瓜皮构造。这是一座天然的火山地质博物馆,具

  4. 40 Years of Processing Pieces of Space

    Science.gov (United States)

    Satterwhite, C. E.; Funk, R. C.; Righter, K.; Harrington, R. H.

    2016-01-01

    representative sample, either a 1-3 gram chip or thin section is sent to the Smithsonian Institution for classification. After Antarctic meteorites have been classified and approved by the Nomenclature Committee of the Meteoritical Society, they are announced in the Antarctic Meteorite Newsletter, which is published twice per year (fall and spring) so that scientists may review which meteorites are available to study. Requests for Antarctic Meteorite samples are welcomed from research scientists, regardless of their current state of funding for meteorite studies. Since its inception over 3,300 requests have been made for pieces of these meteorites and over 400 investigators worldwide are active in the study of meteorites.. Research on these samples has been published in more than1500 peer reviewed articles; a listing of papers for any meteorite sample can be generated by accessing http://curator.jsc.nasa.gov/antmet/referencesearch.cfm. Antarctic meteorite samples requested by scientists are prepared several different ways. Most samples are prepared as chips, either using a rock splitter or using a chisel and chipping bowl. In special situations, a researcher may request a meteorite slab in which case the samples are cut using a diamond-bladed bandsaw inside of a dry nitrogen glove box. The meteorites are always cut in a 100 percent liquid-free environment. Additionally, thin/thick sections of Antarctic meteorites are also prepared at JSC. The meteorite thin section lab at JSC can prepare standard 30-micron thin sections, thick sections of variable thickness (100 to 200 microns), or demountable sections using superglue, all section are prepared without using water. Although many of the techniques used back in the '70's are still used today, advances in computers, software, databases, available tools and instrumentation have helped to streamline and shorten the duration of the classification process. In conjunction with present day missions to asteroids and other planets

  5. Effect of blade vibration on mulch tillage performance under silt clay loam soil

    Directory of Open Access Journals (Sweden)

    B Goudarzi

    2015-09-01

    Full Text Available Introduction: Mulch tillage system is an intermediate system which covers some of disadvantages of no tillage and conventional tillage systems. In farms in which tillage is done with a chisel plow, runoff and soil erosion have a less important relation to moldboard and disk plow and naturally absorption of rainfall will be developed. Thus, the mulch tillage system is an appropriate alternative to conventional tillage and no tillage (Backingham and Pauli, 1993. The unwanted vibration in machinery and industry mainly processes most harmful factors, for example: bearing wear, cracking and loosening joints. And noise is produced in electrical systems by creating a short circuit (Wok, 2011. Self-induced and induced vibration are used in tillage systems. Induced vibration is created by energy consumption and self-induced vibration is created by collision among the blades and soil at the shank (Soeharsono and Setiawan, 2010. A study by Mohammadi-gol et al. (2005 was conducted. It was found that on the disk plow, plant residues maintained on the soil are more than that of moldboard plow. 99% frequency and amplitude, speed and rack angle of blade directly affect soil inversion and indirectly affect preservation of crop residue on the soil. The effect of vibration frequency and rack angle of blade to reduce the tensile strength is also clear. Moreover, in contrast to previous studies when speed progressing is less than (λ, not only the relative speed (λ, but also frequency can reduce the tensile strength (Beiranvand and Shahgoli, 2010; Awad-Allah et al., 2009. Therefore, aim of this study was to determine the effect of vibration and the speed of tillage on soil parameters and drawbar power in using electric power. Materials and Methods: To perform this test, three different modes of vibration (fixed, variable and induced vibration and two levels of speed in real terms at a depth of 20 cm were used for farming. The test was performed with a split plot

  6. Efeitos de sistemas de preparo nas propriedades físicas de um Latossolo Vermelho distrófico Effects of tillage systems on the soil physical properties of a dystrophic Red Latosol

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    Karina Maria Vieira Cavalieri

    2006-02-01

    residue management are essential for the sustainability of cassava production in sandy and sandy loam soils of Northwestern Paraná State, Southern Brazil. The objective of this study was to evaluate the effects of different tillage systems used for planting cassava: no-tillage (NT, minimum tillage using chiseling (MT and conventional tillage with moldboard plow and disking (CT on some physical properties of a dystrophic Red Latosol. The following soil physical properties were evaluated in the 0-0.15 m and 0.15-0.30 m soil layers: soil bulk density (BD, soil water retention curve, soil resistance to penetration curve and least limiting water range (LLWR. Higher values of BD and soil resistance to penetration were verified in the NT and MT treatments. The soil water retention curve was only influenced by BD, which incorporated the effects of the soil tillage systems independent of sampled layers. The soil resistance curve to penetration was influenced by tillage systems and layers, indicating that the soil resistance to root penetration was higher in NT > MT > CT, and was accentuated at the 0.15-0.30 m depth. The increase in the BD led to a reduction in the LLWR due to the effects of soil resistance to penetration and air-filled porosity, which in turn determined the range of soil available water. Results indicated that LLWR value followed the sequence: PC = PM > PSR in the 0-0.15 m soil layer, and was not influenced by tillage systems in the 0.15-0.30 soil layer The critical bulk density value (BDc, the BD value at which LLWR = 0, was lower in NT and MT tillage systems compared with CT, therefore resulting in a smaller frequency of higher BD values than BDc in the soil under CT.

  7. Aggregate stability as affected by short and long-term tillage systems and nutrient sources of a hapludox in southern Brazil Efeitos de curto e de longo prazo da aplicação de sistemas de manejo do solo e de fontes de nutrientes sobre a estabilidade de agregados, em um nitossolo vermelho

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    Milton da Veiga

    2009-08-01

    Full Text Available The ability of a soil to keep its structure under the erosive action of water is usually high in natural conditions and decreases under frequent and intensive cultivation. The effect of five tillage systems (NT = no-till; CP = chisel plowing and one secondary disking; CT = primary and two secondary distings; CTb = CT with crop residue burning; and CTr = CT with removal of crop residues from the field, combined with five nutrient sources (C = control, no nutrient application; MF = mineral fertilizers according to technical recommendations for each crop; PL = 5 Mg ha-1 y-1 fresh matter of poultry litter; CM = 60 m³ ha-1 y-1 slurry cattle manure; and SM = 40 m³ ha-1 y-1 slurry swine manure on wet-aggregate stability was determined after nine years (four sampled soil layers and on five sampling dates in the 10th year (two sampled soil layers of the experiment. The size distribution of the air-dried aggregates was strongly affected by soil bulk density, and greater values of geometric mean diameter (GMD AD found in some soil tillage or layer may be partly due to the higher compaction degree. After nine years, the GMD AD on the surface was greater in NT and CP compared to conventional tillage systems (CT, CTb and CTr, due to the higher organic matter content, as well as less soil mobilization. Aggregate stability in water, on the other hand, was affected by the low variation in previous gravimetric moisture of aggregates, which contributed to a high coefficient of variation of this attribute. The geometric mean diameter of water-stable aggregates (GMD WS was highest in the 0.00-0.05 m layer in the NT system, in the layers 0.05-0.10 and 0.12-0.17 m in the CT, and values were intermediate in CP. The stability index (SI in the surface layers was greater in treatments where crop residues were kept in the field (NT, CP and CT, which is associated with soil organic matter content. No differences were found in the layer 0.27-0.32 m. The effect of nutrient

  8. Análise técnica de fontes de nutrientes associadas a sistemas de preparo do solo Nutrient sources associated with soil tillage systems: technical aspects

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    Carla Maria Pandolfo

    2008-04-01

    crop attributes. The study was carried out at an experimental station of Epagri in Campos Novos, on a Typic Hapludox, in a long-term experiment. The treatments were a combination of five tillage systems (no-till, chisel plow, conventional tillage, conventional tillage with burned crop residues, and conventional tillage with crop residues removal with five nutrient sources (TES = control, without fertilizer; AM = mineral fertilizer according with technical recommendation for each crop; CA = 5 Mg ha-1 year-1 of moist poultry litter; DLB = 60 m³ ha-1 year-1 of liquid cattle manure; and, DLS = 40 m³ ha-1 year-1 of liquid pig manure. A model was established to evaluate the nutrient sources use. The model was fed data of soil and crop attributes, that were transformed into the respective indexes. A model was used to quantify and analyze the effect of nutrient sources on technical aspects of each soil management type. The outputs were triangular pictures and their areas, with the respective confidence limits (p < 0.10. The nutrient sources did not differ when the plant, chemical and physical indexes were considered together, whereas results of poultry litter were best when evaluated by the chemical or the plant index. The technical behavior of the nutrient sources and the physical index in particular were related to soil tillage. Among the evaluated tillage systems, no-till performed best and the conventional system with straw removal worst. The model used to analyze the technical aspects was an efficient tool for a more comprehensive evaluation of the use of organic nutrient sources.

  9. Efecto acumulativo de la siembra directa sobre algunas características del suelo en la región semiárida central de Argentina Long term effect of no-tillage on some soil properties in the central semiarid region of Argentina

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    Adriana Abril

    2005-12-01

    recent adoption of no-tillage practices in the country. Moreover, most of the available research on no-tillage in Argentina refers to the humid Pampas region. In contrast, information on the semi-arid region is very scarce, despite the fact that an increased cover stubble is particularly useful in water-limited soils. In this paper we report a long-term evaluation (5 and 10 years periods of no-tillage practices on a chemical (SOM, total N and NO3-N and biological (microbial biomass and activity soil characteristics, and b quantity, identifiable fractions, and chemical quality of stubble material in soybean monoculture and soybean-corn rotation. Research was conducted at Manfredi INTA Experimental Station in semi-arid, central Argentina (31°49' S and 63°46' W. Soils under no-tillage system had higher SOM and total N content compared with control (conservation tillage with chisel plow in both, soybean monoculture and soybean-corn rotations. The observed difference increased with time (10 and 20% at 5 and 10 years, respectively. Nitrate content, and microbial activity and biomass showed high variability in the measurement periods, depending on climatic condition at the sampling date. Stubble cover was greater in the corn-soybean rotation with corn as preceding crop (2473.9 g m-2 than in soybean monoculture (1035.7 g m-2. The stubble non-identifiable fraction was very significant in all treatments (ranging between 2-10 t ha-1, which would favor new surface soil formation. The soybean-corn rotation with soybean as preceding crop showed the lowest values in all chemical parameters, particularly in soluble compounds (nitrate, ammonium and soluble carbon. Contrarily with what is usually assumed, our results suggest that nutrient release from long-term stubble may become a significant nutrient source for the crops. Therefore, this nutrient source should be considered when evaluating crop fertilization requirements.

  10. The "green stones" of Valtellina and Valchiavenna (central Alps, northern Italy)

    Science.gov (United States)

    Cavallo, Alessandro

    2015-04-01

    folded, and are processed in two main commercial varieties: schistose ("serpentinoscisto") and massive ("serpentino da taglio"). In Valmalenco, the extraction and processing of schistose serpentinites for the production of slabs ("piode", splitted by hand with hammer and chisel), used in roofing and flooring, dates back at least to the XIV century. From the traditional underground extraction, the quarrying activities moved to the modern open-cast extraction in the seventies. The renowned quality of the secular serpentinite roof coverings is related to the excellent physical and mechanical properties, especially the flexural strength (average values around 90-100 MPa), very low porosity and the thaw/freezing resistance. The "massive" serpentinite achieved a special place in the national and international market of ornamental stones: the several extracted varieties (Serpentino Classico, Verde Vittoria, Verde Perlato, Verde Mare, Verde Principe, Verde Torre S. Maria), in addition to the excellent technical properties (flexural strength and thermal properties) that promote specific uses, make these stones much appreciated worldwide (e.g. Bundestag in Berlin, Germany). As part of the "green stones" of Valmalenco, two currently abandoned ophicalcite quarries have been active in the recent past. The extraction and processing of soapstone ("pietra ollare" or "pietra laugera", a talc and/or chlorite rich ultramafic/mafic rock) in Valmalenco and Valchiavenna probably dates back to the Iron Age; in Valchiavenna it is documented with certainty since Roman times and the Middle Ages. The extraction and processing of soapstone peaked around the middle of the XVIII century, with a dozen quarries and about 300 workers involved, between Chiavenna and Piuro. A limited production of soapstone is still active in the municipalities of Piuro (talc-olivine-tremolite fels) and Chiesa in Valmalenco (chlorite schist), where in addition to the traditional cooking pots ("Lavecc"), there is a growing

  11. Teoria laneana: a univocidade radical aliada à dialética-materialista na criação da psicologia social histórico-humana Lanean theory: the radical unambiguousness allied with the dialectic-materialist in creating historical-human social psycology

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    Bader Burihan Sawaia

    2007-01-01

    sua concepção-compromisso de ciência em busca do conhecimento da existência humana sem suturas.The paper presents the base of Sílvia Lane's theoretical-methodological work, highlighting its ontological and epistemological presumptions and delineating the grand moments of its configuration process. The dialectic process that advances incorporating new knowledge without abandoning the previous, but uniting it in producing something new. This "pragmatic-critical-revolutionary" methodology, initially intuitive, became scientifically chiseled out from empirical research, according to Lane, fundamental for criticizing the concepts and advancing the theory. The task of the text is easy because Sílvia registered in her books each change of her principal interests, analytical categories and philosophical reflections. There are four moments to be highlighted. All of them make a profound study of her radical theoretical overcome: the transition of a configured reference in the interface between Lewin, Mead, Skinner to Marxism: 1 from the 70's, marked by the privileged dialogue with representations theory and with concerns with language and social groups; 2 from the 80's, a time of vigorous reflections on a new conception of man for psychology, with emphasis on the categories of consciences and alienation, orientated by soviet psychology and neo-marxism (Politzer and Heller; 3 from the 90's, characterized by the reflection on the role of subjectivity/affectivity on social awareness and on transformative action, overcoming the subject's imprisonment to exteriority and to pure repetition and the purge of singularity, and by reaffirming participant research and community praxis; 4 from the new millennium, dedicated to unveil the secrets of human creativity. Emotion, art and creativity were the themes that became to mediate her incessant critical thoughts on psychology's theories and practical consequences for Latin America's social condition. Thus, this paper hopes to present

  12. Aspectos econômicos do uso de fontes orgânicas de nutrientes associadas a sistemas de preparo do solo Economical aspects of organic nutrient sources associated with soil tillage systems

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    Carla Maria Pandolfo

    2008-09-01

    ário, P e K, após nove anos de aplicação das fontes de nutrientes, tem importante participação no desempenho econômico das mesmas.Economical analysis is important to make decision on the use of organic nutrient sources. The objective of this study was to elaborate an economical analysis of different nutrient sources to help farmers and technicians to make decision about the use of these sources at different soil management. The study was carried out at the Epagri Experimental Station of Campos Novos, using a long-term experiment. The treatments were a combination of five tillage systems (no-till; chisel plow; conventional tillage; conventional tillage with crop residues burned and conventional tillage with crop residues removed from the field, with four nutrient sources (TES=control, no fertilizer; AM=mineral fertilizer according with technical recommendation for each crop; EA=5mg ha-1 of moisture poultry litter; ELB=60m³ ha-1 of liquid cattle manure; and ELS=40m³ ha-1 of slurry pig manure. The economical attributes used were variable costs of production, total income, and the cost of the necessity of lime and fertilizers application to improve soil chemical condition after nine years of applying treatments. A model was used to quantify and analyse the effect of nutrient sources in economical aspects, for each nutrient source within each soil tillage. The outputs were triangular pictures and their areas with 90% confidence limits. It was concluded that economical aspect effects of the organic nutrient sources were dependent on tillage systems, and the better performance was in no-till system. EA and ELS showed better economical results. ELS and ELB, even showing different picture areas, were the sources that showed lesser variability in economical attribute evaluated, and did not have one highlight attribute among them. The use of cost of the necessity of lime and fertilizers application to improve soil chemical condition after nine years of applying treatments

  13. Comparative study of complications among routine method,high speed turbine handpiece and piezosurgery device after extraction of impacted wisdom teeth%高速涡轮钻、超声骨刀和常规方法拔除下颌阻生智牙的比较

    Institute of Scientific and Technical Information of China (English)

    郭照中; 张恒; 李焱; 李欣; 刘荫; 王杨; 袁春霞; 刘学

    2012-01-01

    目的:通过比较常规拔牙法、高速涡轮钻、超声骨刀拔除邻近神经管下颌阻生智牙并发症的客观数据,寻求拔除此类牙的最佳方法.方法:将300例符合条件的患者随机均分为3组,A组采用骨凿、劈冠、增隙法拔牙,B组用高速涡轮钻,C组用超声骨刀拔牙.观察3组患者手术时间、术后疼痛持续时间、干槽症和下牙槽神经损伤发生情况.采用SPSS 13.0软件包对计量资料进行配对t检验,对计数资料进行x2检验.结果:手术时间A组为(14.12±0.12)min,B组为(7.22±0.15)min,C组为(25.23±0.32)min;3组间两两比较均有显著差异(P<0.05).术后疼痛持续时间A组为(62.15±1.51)h,B组为(48.23±1.23)h,C组为(14.34±0.80)h;3组间两两比较均有显著差异(P<0.05).干槽症发生例数A组为9例,B组为2例,C组为1例.下牙槽神经损伤A组6例,B组2例,C组0例.结论:与常规拔牙方法相比,高速涡轮钻拔除复杂阻生牙能缩短手术时间,减少术后并发症,超声骨刀和前2种方法相比虽然手术时间较长,但术后并发症更少.%PURPOSE: To investigate complications in extraction of complicated impacted wisdom teeth whose root apex near to the inferior alveolar nerve (IAN) by using routine method (chisels),high speed turbine handpiece and piezosurgery device respectively. METHODS: Three hundred qualified patients with impacted wisdom teeth were divided into three groups randomly,one hundred patients in group A were extracted by routine method, one hundred patients in group B were extracted by high speed turbine handpiece , and one hundred patients in group C were extracted by piezosurgery device. The operation time,postoperative pain duration,dry socket and IAN injury were compared between each two groups. All statistical analysis was performed using SPSS 13.0 software package. Differences between groups were compared using a paired t test (quantitative data) or Chi-square test (qualitative data). RESULTS: The

  14. Assessing agricultural management effects on structure related soil hydraulic properties by tension infiltrometry

    Science.gov (United States)

    Bodner, G.; Loiskandl, W.; Kaul, H.-P.

    2009-04-01

    different intensities including conventional tillage with a mouldboard plough, reduced tillage with a chisel plough and no-tillage. The results showed that the plant-based management measure of cover cropping had only minor influence on near-saturated hydraulic conductivity (kh) and flow weighted mean pore radius (λm). Substantial over-winter changes were found with a significant increase in kh and a reduction in the pore radius. A spatial trend in soil texture along the cover cropped slope resulted in a higher kh at lower pressure heads at the summit with higher fractions of coarse particles, while kh tended to be highest at the toeslope towards saturation. Cover crop management accounted for a maximum of 9.7% of the total variability in kh, with a decreasing impact towards the unsaturated range. A substantial difference to bare soil in the cover cropped treatments could be identified in relation to a stabilization of macro-pores over winter. The different tillage treatments had a substantial impact on near-saturated kh and pore radius. Although conventional tillage showed the highest values in kh and λm, settling of the soil after the ploughing event tended to reduce differences over time compared to the other tillage methods. The long-term no-tillage (10 years) however had the lowest values of kh at all measurement dates. The high contents of silt and fine sand probably resulted in soil densification that was not counterbalanced sufficiently by biological structure forming agents. The study could show that soil structure related hydraulic properties are subject to a substantial seasonal variability. A comprehensive assessment of agricultural measures such as tillage or cover cropping requires an estimate of these temporal dynamics and their interaction with the management strategies. Particularly for plant-based management measures such as cover cropping, which represent a less intense intervention in the structural states of the soil compared to tillage, this was

  15. Controlo da salinidade do solo com recurso à sementeira directa Control of the soil salinity by using direct drilling

    Directory of Open Access Journals (Sweden)

    J. P. Mendes

    2009-01-01

    mais baixos de condutividade eléctrica da solução do solo ao fim de dois anos são indicadores, de que, a sementeira directa, em conjunto com uma cultura de cobertura, poderá ser uma ferramenta útil na prática de uma agricultura de regadio sustentável, em clima semi-árido e em solos de baixa condutividade hidráulica, mesmo utilizando águas de rega com condutividade eléctrica (CE moderada.The use of water with moderated salt content for irrigation under semi-arid conditions, especially on soils with low saturated hydraulic conductivity, can lead to an increase of the salt content of the soil and even to an increase of exchangeable Na. This is a possible scenario in the Alqueva irrigation program in the South of Portugal. The present study aims to evaluate the potential of direct drilling and soil mulching as a way to improve infiltration and reduce evaporation, in order to reduce salt accumulation during the summer and to improve leaching during the winter. The trial has been carried out on a Calcic Luvisols (FAO classification under centre pivot irrigation. There were used two soil tillage treatments (direct drilling and traditional - chisel plow plus two disc arrows, two levels of water salinity (0.7 dS m-1 and 2 dS m-1 and two water regimes (100% and 70% of Etc. The experimental design is a split plot, with tillage as the reference treatment. After the second year the salinity in the top 0.20 m of the soil is lower under direct drilling (0.63 dS m-1 than under traditional tillage system (0.75 dS m-1. The differences between tillage treatments are more evident for the higher water regime. The lowest values of electric conductivity in soil solution at the end of two years, indicate that direct drilling together with cover crop, can be a useful tool in irrigation under semi-arid conditions, in soils with low values of hydraulic conductivity, even when using water with moderated electrical conductivity (EC.

  16. Variabilidade espacial da resistência do solo à penetração e da taxa de estratificação de carbono orgânico do solo em um Latossolo Vermelho eutroférrico Spatial variability of soil resistance to penetration and soil organic carbon stratification ratio on a Typic Eutrothox

    Directory of Open Access Journals (Sweden)

    Jonez Fidalski

    2006-12-01

    no-tillage with rotation of cultures and no-tillage with succession of cultures associated the chiselling. The study was set up from May to June of 2002, in Palotina, west region of the state of Parana, Brazil. The samples for determination the soil bulk density, soil resistance to penetration and soil organic carbon stratification ratio were obtained in 120 points in 2 x 5m grid, in the 0.40m depth. Soil resistance to penetration measures were made three times, in a period of 10 days, initiate after having interrupted precipitation. The soil bulk density did not explain the spatial dependence of the compaction of the soil. The soil resistance to penetration and soil organic carbon stratification ratio presented range of 17m. The temporal variation of the spatial dependence of the soil resistance to penetration happens in the 0.05-0.20m layers. Similares spatial e dependence of the soil resistance to penetration and soil organic carbon stratification ratio reveals the importance of the quality of the soil in the spatial and temporary stabilization of the compaction of the soil expresses for the soil resistance to penetration in no-tillage systems.

  17. The barley straw residues avoid high erosion rates in persimmon plantations. Eastern Spain

    Science.gov (United States)

    Cerdà, Artemi; González Pelayo, Óscar; Giménez-Morera, Antonio; Jordán, Antonio; Novara, Agata; Pereira, Paulo; Mataix-Solera, Jorge

    2015-04-01

    distributed soil erosion and sediment delivery model (WATEM/SEDEM) in Northern Ethiopia. Land Degradation & Development 24, 188-204. DOI 10.1002/ldr.1121 Lavigne, C., Achard, R., Tixier, P., Lesueur Jannoyer, M. 2012. How to integrate cover crops to enhance sustainability in banana and citrus cropping systems. Acta Horticulturae 928, 351-358. Le Bellec, F., Damas, O., Boullenger, G., Vannière, H., Lesueur Jannoyer, M., Tournebize, R., Ozier Lafontaine, H. 2012. Weed control with a cover crop (Neonotonia wightii) in mandarin orchards in Guadeloupe (FWI). Acta Horticulturae 928, 359-366. Liu, Y., Tao, Y., Wan, K.Y., Zhang, G.S., Liu, D.B., Xiong, G.Y., Chen, F. 2012. Runoff and nutrient losses in citrus orchards on sloping land subjected to different surface mulching practices in the Danjiangkou Reservoir area of China. Agricultural Water Management 110, 34-40. Lu, J., Wilson, M.J., Yu, J. 1997. Effects of trench planting and soil chiselling on soil properties and citrus production in hilly ultisols of China Soil and Tillage Research 43, 309-318. Lü, W., Zhang, H., Wu, Y., Cheng, J., Li, J., Wang, X. 2012. The impact of plant hedgerow in Three Gorges on the soil chemicophysical properties and soil erosion. Key Engineering Materials 500 142-148. Liu, Y., Tao, Y., Wan, K.Y., Zhang, G.S., Liu, D.B., Xiong, G.Y., Chen, F. 2012. Runoff and nutrient losses in citrus orchards on sloping land subjected to different surface mulching practices in the Danjiangkou Reservoir area of China. Agricultural Water Management 110, 34-40. Lu, J., Wilson, M.J., Yu, J. 1997. Effects of trench planting and soil chiselling on soil properties and citrus production in hilly ultisols of China Soil and Tillage Research 43, 309-318. Lü, W., Zhang, H., Wu, Y., Cheng, J., Li, J., Wang, X. 2012. The impact of plant hedgerow in Three Gorges on the soil chemicophysical properties and soil erosion. Key Engineering Materials 500 142-148. Mahmoud, E., Abd El-Kader, N. 2014. Heavy metal immobilization in

  18. Extreme soil erosion rates in citrus slope plantations and control strategies. A literature review

    Science.gov (United States)

    Cerdà, Artemi; Ángel González Peñaloza, Félix; Pereira, Paulo; Reyes Ruiz Gallardo, José; García Orenes, Fuensanta; Burguet, María

    2013-04-01

    approach. Catena, 85 (3), 231-236. Cerdà, A., Jurgensen, M.F., Bodi, M.B. 2009. Effects of ants on water and soil losses from organically-managed citrus orchards in eastern Spain. Biologia, 64 (3), 527-531. Cerdà, A., Morera, A.G., Bodí, M.B. 2009. Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34 (13), 1822-1830. Lavigne, C., Achard, R., Tixier, P., Lesueur Jannoyer, M. 2012. How to integrate cover crops to enhance sustainability in banana and citrus cropping systems. Acta Horticulturae, 928, 351-358. Le Bellec, F., Damas, O., Boullenger, G., Vannière, H., Lesueur Jannoyer, M., Tournebize, R., Ozier Lafontaine, H. 2012. Weed control with a cover crop (Neonotonia wightii) in mandarin orchards in Guadeloupe (FWI). Acta Horticulturae, 928, 359-366. Liu, Y., Tao, Y., Wan, K.Y., Zhang, G.S., Liu, D.B., Xiong, G.Y., Chen, F. 2012. Runoff and nutrient losses in citrus orchards on sloping land subjected to different surface mulching practices in the Danjiangkou Reservoir area of China. Agricultural Water Management, 110, 34-40. Lu, J., Wilson, M.J., Yu, J. 1997. Effects of trench planting and soil chiselling on soil properties and citrus production in hilly ultisols of China Soil and Tillage Research, 43 (3-4), 309-318. Lü, W., Zhang, H., Wu, Y., Cheng, J., Li, J., Wang, X. 2012. The impact of plant hedgerow in Three Gorges on the soil chemicophysical properties and soil erosion. Key Engineering Materials, 500, 142-148. Wang, L., Tang, L., Wang, X., Chen, F. 2010. Effects of alley crop planting on soil and nutrient losses in the citrus orchards of the Three Gorges Region. Soil and Tillage Research, 110 (2), 243-250. Wu J., Li Q., Yan L. 1997. Effect of intercropping on soil erosion in young citrus plantation - a simulation study. Chinese Journal of Applied Ecology, 8 (2), 143-146. Wu, D.-M., Yu, Y.-C., Xia, L.-Z., Yin, S.-X., Yang, L.-Z. 2011. Soil fertility indices of citrus

  19. STUDY ON STONE ARTIFACT RESOURCE CATCHMENTS IN THE XIAOHUANGSHAN SITE,ZHEJIANG PROVINCE%浙江嵊州小黄山遗址石制品资源域研究

    Institute of Scientific and Technical Information of China (English)

    何中源; 张居中; 杨晓勇; 王海明; 张恒

    2012-01-01

    valley takes shape in mountainous areas,thus it is conjectured that those raw materials could be brought from the mountain area to the Xinsheng Basin. According to the present stream network of watershed,it is inferred that most of raw materials could be easily obtained from Chongren River,ca. 320m north of the site and the Changle River, ca. 1400m southeast of the site. However,more attention must be paid to sources of stones,it is proposed that ancient people obtained basalt mainly from the Chongren River, while shale and granite only can be found in Changle River, and the rest raw materials can be obtained from both rivers. All these foundings indicate that Xiaohuangshan people had a good knowledge and sense of selectivity on different kinds of rocks.Relationships between stone artifacts and lithology of raw materials were also examined in this paper. About 88. 8% of grinding slabs and hand-stones were made of basalt, they differ sharply from many sites' grinding tools made on sandstones. Many tools which were edged,such as stone axes,adzes and chisels were made of diabase or shale. Chalcedony was made into stone bails almost. Such differences prove that Xiaohuangshan people had some empirical knowledge on properties of different lithic raw materials, and they were able to select different materials to produce a variety of implements.To sum up,the analysis of Stone Artifact Resource Catchments in the Xiaohuangshan Site shows that collecting rock pieces from rivers around the site was the principal strategies of raw material exploitation adopted by the Xiaohuangshan people. They chose different kinds of rock pieces collected from the river bed as raw materials and they also had an empirical knowledge on properties of different rocks. The choosing for basalt to make grinding slabs may be related to people's favorable characteristics, however, this assumption requires more evidences.%本文采用“遗址内”(on-site)的资源域分析方法,通过对小黄山遗址

  20. MAIZE COSTS AND PROFITABILITY ACCORDING TO SOIL MANAGEMENT AND NITROGEN FERTILIZATION CUSTOS E RENTABILIDADE DO MILHO EM FUNÇÃO DO MANEJO DO SOLO E DA ADUBAÇÃO NITROGENADA

    Directory of Open Access Journals (Sweden)

    Rafael Gonçalves Vilela

    2009-12-01

    Full Text Available

    Agronomic practices that help farmers to raise yield and reduce costs must be studied to ensure agricultural sustainability. Thus, the objective of this study was to analyze economically the effect of soil management and nitrogen fertilization in maize crops. Treatments consisted of a combination of 3 soil management techniques (plow harrows + floating harrows, chisel + floating harrows, and no-tillage, 5 periods of nitrogen fertilization (control - 0 kg ha-1 N; 120 kg ha-1 after sowing (S; 120 kg ha-1 in the V6 stage; 30 kg ha-1 (S + 90 kg  ha-1 in V6; 30 kg ha-1 (S + 45 kg ha-1 in V4 + 45 kg ha-1 in V

  1. Redução da erosão hídrica em três sistemas de manejo do solo em um Cambissolo Húmico da região do Planalto Sul-Catarinense Reduction of water erosion in three soil management systems in an Inceptisol of the Planalto Sul-Catarinense region - Brazil

    Directory of Open Access Journals (Sweden)

    André Júlio do Amaral

    2008-10-01

    (Glycine max, L crop cycles, using conventional (one plowing and two diskings, reduced (one chiseling and one disking, and no tillage (direct seeding, to determine the erosion and effectiveness of runoff reduction of these forms of soil use and management. The experiment was planted on a silt clay loam Inceptisol, with 0.102 m m-1 mean slope steepness. Plant and water-rainfall erosion parameters were evaluated in five crop stages, defined on the basis of percent of soil cover per plant canopy. The total rainfall amount was about the same (approximately 650 mm in both crop cycles, with some variation in distribution, but with a greater concentration in the period from the middle to the end of the wheat cycle and the initial period of soybean. The rain erosivity pattern was similar, but with clearly different absolute values in each crop cycle (1,545 MJ mm ha-1 h-1 in wheat and 2,573 MJ mm ha-1 h-1 in soybean. The determined mean annual value of the soil erodibility index (factor K in the USLE or RUSLE erosion prediction model was equal to 0.018 Mg ha h ha-1 MJ-1 mm-1. The mean annual losses of soil and water were generally relatively small in all situations studied, although soil losses were greater in wheat and water losses higher in soybean. Both loss types decreased in the order conventional-, reduced-, and no-tillage. The soil loss was proportionally much more reduced by tillage than by water loss. The provisionally determined mean annual values of the C factor - soil cover and management in USLE or in RUSLE erosion prediction model for the wheat-soybean crop sequence in the experimental climatic conditions were 0.23 when using conventional tillage, 0.06 for reduced tillage, and 0.023 for no-tillage or direct seeding.

  2. Biodiversity impact of the aeolian periglacial geomorphologic evolution of the Fontainebleau Massif (France)

    Science.gov (United States)

    Thiry, M.; Liron, M. N.

    2009-04-01

    erosion of the sand beneath the bordering sandstone benches, resulting in overhangs. These structures are the most common in the western district of the Fontainebleau Massif. Ponds develop on the tightly silicified and impermeable sandstone pans that form the "platières". There are permanent ponds and temporary wet zones, formed of interconnected or isolated depressions. The origin of these ponds has to be questioned with regard to the landscape shaping. Their origin is directly bound to the hollowing of uncemented, sandy zones, within the sandstone pans forming the "platières". Erosion by runoff cannot be considered; the only way to hollow them out is by deflation processes. No direct dating of the Quaternary dune and loess deposits of the Fontainebleau Massif exists. Nevertheless, dating of paleopodzols interlayered between drift sands, pond deposits and bones within congelifracts allow relating these periglacial features with the end of the last glacial period. For now, there is no dating to assess what belongs to older glacial periods. Distribution of the aeolian patterns The Fontainebleau Massif displays noteworthy morphological diversities in the various districts of the forest. Some of these differentiations result from geological features, but most of them are related to erosion processes, and among them deflation processes leaved different imprints in the western and eastern districts of the Fontainebleau Massif. The topography played an important role controlling the aeolian processes. Deflation was important in the westerly upwind district. In the westerly front face, aeolian erosion was activated by turbulences around the topographic obstacles. The reliefs funneled the winds and gave rise to swirls that hollow the blowouts. This area displays the sharpest and more chiseled landforms of the massif. Moreover, the sandstone scarps at the edge of the "platières" are high and uncovered, with frequent overhangs. The collapsed sandstone blocks of the "chaos" are

  3. The use of straw mulch as a strategy to prevent extreme soil erosion rates in citrus orchard. A Rainfall simulation approach

    Science.gov (United States)

    Cerdà, Artemi; Giménez-Morera, Antonio; Jordán, Antonio; Pereira, Paulo; Novara, Agata; García-Orenes, Fuensanta

    2014-05-01

    -115. 10.1016/j.still.2010.05.005. García-Orenes, F., Roldán, A., Mataix-Solera, J., Cerdà, A., Campoy, M., Arcenegui, V., Caravaca, F. 2012. Soil structural stability and erosion rates influenced by agricultural management practices in a semi-arid Mediterranean agro-ecosystem. Soil Use and Management 28, 571-579. DOI: 10.1111/j.1475-2743.2012.00451.x Haregeweyn, N., Poesen, J., Verstraeten, G., Govers, G., de Vente, J., Nyssen, J., Deckers, J., Moeyersons, J. 2013. Assessing the performance of a Spatially distributed soil erosion and sediment delivery model (WATEM/SEDEM) in Northern Ethiopia. Land Degradation & Development 24, 188-204. DOI 10.1002/ldr.1121 Iranzo, M., Cañizares, J.V., Roca-Perez, L., Sainz-Pardo, I., Mormeneo, S., Boluda, R. 2004. Characteristics of rice straw and sewage sludge as composting materials in Valencia (Spain). Bioresource Technology 95, 107-112 Le Bellec, F., Damas, O., Boullenger, G., Vannière, H., Lesueur Jannoyer, M., Tournebize, R., Ozier Lafontaine, H. 2012. Weed control with a cover crop (Neonotonia wightii) in mandarin orchards in Guadeloupe (FWI). Acta Horticulturae 928, 359-366. Liu, Y., Tao, Y., Wan, K.Y., Zhang, G.S., Liu, D.B., Xiong, G.Y., Chen, F. 2012. Runoff and nutrient losses in citrus orchards on sloping land subjected to different surface mulching practices in the Danjiangkou Reservoir area of China. Agricultural Water Management 110, 34-40. Lu, J., Wilson, M.J., Yu, J. 1997. Effects of trench planting and soil chiselling on soil properties and citrusproduction in hilly ultisols of China Soil and Tillage Research 43, 309-318. Lü, W., Zhang, H., Wu, Y., Cheng, J., Li, J., Wang, X. 2012. The impact of plant hedgerow in Three Gorges on the soil chemicophysical properties and soil erosion. Key Engineering Materials 500 142-148. Robichaud, P.R., Lewis, S.A., Wagenbrenner, J.W., Ashmun, L.E., Brown, R.E. 2013a. Post-fire mulching for runoff and erosion mitigation. Part I: Effectiveness at reducing hillslope erosion rates

  4. SUSTAINABILITY EFFECTS OF Crotalaria juncea L. AND Crotalaria spectabilis ROTH ON SOIL FERTILITY AND SOIL CONSERVATION

    Science.gov (United States)

    László, Márton, ,, Dr.

    2010-05-01

    fertility. The first set of actions, such as lime application, erosion control measures, and chiseling of sub-surfacehardpan, are "one time" investments which often benefit not only the farming communities but also society at large, improved water quality, food security, etc. Costsharing among all beneficiaries in society should be the carefully thought about. The second set of actions relates to the protection and or maintance of the enhanced soil capital, through balanced plant nutrition applications, appropriate crop rotations, etc., the cost of which have definitely to be fully supported by farmers. However, farmers will bear these costs only if the economic, institutional and legal frame conditions are favourable, i. e. when there are enough incentives to reinvest instead of consuming the capital stock. Possible interventions to enhance soil fertility management, therefore, range from policies affecting farm gate prices, security of land use, access to credit, access to markets, relations between input and output prices, fertilizer supply and distribution right through to access to information on improved soil fertility management (soil organic matter management, prevention of nutrient losses by run off - leaching, efficient use of fertilizers). This cannot be obtained with isolated measures and projects but requires a coherent strategy for soil fertility enhancement and sustainable soil management (Janssen 1993). The implementation of such a strategy, finally, requires a strong commitment of national governments which was often lacking in the past, as well as support from the international community. Neither human needs are satisfied, especially food demands, nor are the natural resources protected. Gross plant production was decreased with twenty percent in the last 10 years. Morever, this inadequate rate is obtained partly by degradation of the environment resulting from overexploiting of soil resources. The reversal of this trend and a sustained increase of