The Application of Complementary Variational Principles in Sinusiodal Electromagnetic Field

Considering the need in practical applications the authors extend thecomplementary variational principles from single-medium to multi-medium. The equivalencebetween variational problems and multi-region boundary value problems is proved,Utilizing theextended functional and complementary functional,we construct the complementary variationalproblem in a sinusoidal el ectromagnetic field.Several special forms in computating differentsinusoidal electromagnetic field problems are given.     

决定宁夏灌区水稻丰歉年的温度关键期及其温度指标

通过分析宁夏灌区水稻丰歉年产量与各时段积温间的相关性,确定了影响宁夏水稻丰歉年的温度关键期是8月中旬～8月下旬(扬花—灌浆前期),并用气象当量法划分出宁夏灌区水稻丰歉年的温度指标(温度当量)为积温值440℃·d和日均温度21℃。为宁夏灌区水稻的选种、育种,以及栽培措施提供科学依据。     

利用"组学"技术检测转基因作物非期望效应的潜在性

检测由遗传修饰引起的非期望效应是进行转基因作物安全性评价的一项重要内容.以“实质等同性”概念为基础的评价方法,重点对转基因作物和非转基因亲本中的关键性成分进行定性、定量分析和比较难以充分考虑到一些不可预见因素的发生.“组学”技术通过对转基因作物的整个功能基因组、蛋白质组以及代谢组进行分析,将结果与非转基因亲本进行比较,完善了目前所广泛采用的以“实质等同性”概念为基础的定向方法.“组学”技术是很有潜力的.综述介绍了功能基因组学、蛋白质组学和代谢组学所用技术的原理和方法,重点讨论了这三大“组学”技术在评价转基因作物非期望效应中的应用和局限性,介绍了转基因食品食用安全性评价中非期望效应检测方面的最新进展.     

Pilotstudie zur Gleichwertigkeit oder Vergleichbarkeit der Korngrößenbestimmung von Bodenproben nach E DIN ISO 11277:06.94 (Pipettmethode) und mit dem Sedigraphen

Pilot study to test the equivalence or comparability of soil‐particle‐size analysis according to E DIN ISO 11277:06.94 (pipette method) and by the use of the sedigraph According to Federal Soil Protection Ordinance (BBodschV), the recommended technique for the determination of particle size is the Köhn method (E DIN ISO 11277:06.94, 1994), a technique that is relatively time consuming and laborious. The BBodSchV, however, allows the application of alternative analytical methods provided the equivalence or comparability to the legally required method is proven. We tested the less laborious sedigraph method to determine the <63 μm fractions of soil particles (coarse (gU), medium (mU), fine silt (fU), and clay (T)) at 30 soil samples from Bavaria. The equivalence of results for the fractions (gU, mU, fU, and T) as derived from the Köhn and sedigraph methods was tested according to the guidelines of E DIN 38402–71:10.01 (2001). Following these guidelines, equivalence exists for none of the fractions gU, mU, fU, and T. The comparability of results for each fraction could nevertheless be established by means of a highly significant linear‐regression model (gU: r² = 0.89; mU: r² = 0.93; fU: r² = 0.84; T: r² = 0.97). An extensive validation of the achieved statistical regressions based on independent samples is planned in a subsequent study. The application of the sedigraph will speed up analyses by approximately 30% as compared to the conventional Köhn method.     

Individual-tree radial growth in a subtropical broad-leaved forest: The role of local neighbourhood competition

Establishing the competitive relationships at the local neighbourhood level is essential for improving our understanding of tree growth dynamics in structurally heterogeneous and species-rich forests. We studied the competitive interactions influencing individual-tree five-year radial growth of the two species Castanopsis fargesii (Franch.) and Quercus fabri (Hance) in a diverse young secondary evergreen broad-leaved forest (EBLF) in eastern China. Different spatially explicit individual-based competition indices were examined for their effectiveness at predicting radial growth. These indices were based on one of the three tree size variables - diameter at breast height (dbh), total height, and crown projection area - and were combined with different approaches to identify potential competitors. Furthermore, we tested for competitive equivalence of conspecific and heterospecific neighbours and analysed the effects of local diversity, initial dbh (measured at the beginning of the five-year growth period) and abiotic environmental variables on individual-tree radial growth. Competition accounted for up to 78% and 75% of radial growth variation in C. fargesii and Q. fabri, respectively. The best results were provided by competition indices using crown projection area as the variable describing tree size and the angular height method as the approach to identify potential competitors (i.e. neighbours greater than the minimum angular height, measured from the base of the target trees, are selected as competitors). Competitive equivalence of conspecific and heterospecific neighbours was found in C. fargesii, whereas heterospecifics were stronger competitors than conspecifics in Q. fabri. We could not detect diversity effects on radial growth. The addition of initial dbh or abiotic environmental variables as further explanatory variables failed to improve the predictive ability of growth models. Our results indicate that diameter growth in this EBLF is largely a function of local neighbourhood competition and suggest that the mode of competition is primarily size-asymmetric. It appears that there may be high competitive equivalence among different species, but this remains to be experimentally tested.     

语境在翻译中的作用

语用学从根本上讲是对语言在一定语境中所体现出来的具体意义的科学。本文就翻译的本质和语境的关系及如何在翻译中结合语境避免误译、死译,从而达到有效交际的目的予以分析。     

胡-鹫变分原理与Hellinger-Reissner变分原理非等价性的证明及其他

本文以传统的Lagrange乘子法证明了胡-鹫原理中的泛函具有3类独立变量,胡-鹫原理与Hellinger-Reissner变分原理的关系是包含与被包含关系;本文还从Hellinger-Reissner变分原理出发建立了线弹性力学的又一广义变分原理,说明对于同一物理问题存在着并不唯一的泛函;作者还对如何建立广义变分原理提出建议。     

Assessing ecological equivalence in biodiversity offset schemes: Key issues and solutions

Habitat loss through development is one of the major causes of biodiversity loss. The increasingly common legal requirement to first avoid, then reduce and, if necessary, offset impacts of plans and projects on biodiversity has however not always been appropriately enforced. The blame lies mainly in bad governance such as patchy monitoring or poorly defined liabilities. Biodiversity offsets also suffer from the lack of formal methods for designing and sizing offset requirements. We address this gap by reviewing different tools, methods and guidelines that have been developed in different regulatory contexts. We then formulate a typology of approaches that variously combine these methods and guidelines. We discuss how these relate to the objectives of offset policies and the components of biodiversity and ecosystems to which they apply. Together, these perspectives should contribute to improving existing methods (e.g. by incorporating time-related issues) and our typology should support the development of offset policies.     

顶部点火上吸式固定床中农业废弃物气化特性分析

为了了解在固定床气化炉中生物质的气化特性和炉内温度演变规律,该研究采用顶部点火上吸式(top-lit up draft,简称TLUD)固定床气化炉研究了农业废弃物的气化行为,重点考察了不同空气流量下炉内温度分布、燃气成分和热值的变化规律,探讨了生物质气化过程机理.结果表明,气化过程明显分为2个阶段,即挥发份的析出和焦炭的缓慢气化.整个气化过程中燃气的热值可稳定维持在3 MJ/m3以上,温度场的演变过程与波传递具有相似性,花生壳和稻壳的最佳空气当量比分别为0.31和0.35,且其燃气中焦油含量很低,分别为0.25、0.49 g/m3.该研究为TLUD固定床气化炉的设计和运行提供了有益的参考.