基于GB/T 29309标准的HALT测试技术分析

本文以标准GB/T 29309-2012为基础,以某款开关电源为例,对HALT试验设备、工作极限与破坏极限、试验步骤及设备运行中注意点等方面展开介绍,为电子产品可靠性测试提供相关探讨。     

二氧化氯在医院含菌废水处理中的应用

二氧化氯混合消毒剂是新一代广谱高效消毒剂,消毒能力是次氯的3～5倍.二氧化氯发生器性能安全可靠,运行稳定,操作方便,对人体无不良作用.介绍了二氧化氯混合消毒剂在中国长城铝业公司职工医院含菌废水处理的应用实例.     

集成膜法水处理工艺的研究与应用

集成膜法除盐系统具有连续产水、出水质量好、易控制、占地少、不需酸碱、利于环保等优点。文章通过对集成膜法水处理技术进行研究与应用,将原有的化学除盐水处理方式改为集成膜法水处理工艺,该方法产水水质高且水质稳定,每年可节约酸碱200 t,阴、阳离子交换树脂10 t,切实解决电厂所面临的产水水质不稳定、酸碱废液排放等问题,有力推动了清洁生产。     

Global Trend of Low-carbon Economy and China's Responses

Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crises,coordinate the economic development,and protect the global climate.The global trend of low-carbon economy finds expression in Green Recovery currently,while,in a long run,it will give rise to a new pattern of world competition in politics,economy,technology,trade and finance.The impact of the...     

面向可持续发展的技术创新:从技术预见到战略选择

本文研究了技术预见、关键技术选择和技术创新之间的关系,从方法学、科学技术观的角度分析了技术预见、关键技术选择在技术创新战略中的地位和作用,提出技术预见和关键技术选择是制订和实施技术创新战略的重要手段和基础,应当成为国家创新体系的重要组成部分。建立面向可持续发展的技术创新体系,对落实全面、协调、可持续的科学发展观,实现社会和谐发展具有战略意义。本文分析了传统的技术创新与可持续发展的差异,提出适应当今经济社会发展方向的技术创新应追求经济、社会和环境效益的统一。本文还探讨了在我国开展技术预见和关键技术选择的方法和应遵循的原则,提出应从战略视角把握关键技术选择,进一步指出在技术预见的基础上促进面向可持续发展的技术创新体系建设对实现我国可持续发展战略目标具有重大意义。     

Effects of plant density on the photosynthetic and chloroplast characteristics of maize under high-yielding conditions

The Science of Nature - Knowledge on animal personality has provided new insights into evolutionary biology and animal ecology, as behavioural types have been shown to affect fitness. Animal...     

Strategic Environmental Assessment： A New Tool for Ecological Urbanization of Coastal Cities in China

Recently, there has been growing concerns about environmental issues related to urbanization in China. The intense natural resources utilization and increasing population has brought great pressure, especially in coastal areas, consequently affecting the sustainable development of coastal cities. In 2002, Environmental Impact Assessment Act （EIA Act） was enacted in China. Environmental impact assessment targeted at planning, one level of strategic environmental assessment （SEA）, thus became a legislative requirement. This paper considers SEA to be one of the important approaches not only to control coastal pollution, but also to conserve coastal ecosystems and finally to achieve sustainable development during urbanization, thus it will be a set an example for other areas of China. The experience of SEA in Xiamen, a coastal city in southeast China, illustrates the potentials of SEA. This paper first briefly introduces the concept and potentials of SEA, then compares two SEA cases and a project EIA case in Xiamen, and finally identifies the key characteristics of SEA.     

Genetic evidence of promiscuity in Peromyscus leucopus

Summary We collected pregnant female Peromyscus leucopus from natural populations during the summer of 1987 and 1988 and allowed these females to give birth to their field-conceived young in the laboratory. Blood samples were taken by suborbital puncture and phenotypes of five genetic loci (Esterase-1, trasferrin, hemoglobin, albumin and 6-phosphogluconate dehydrogenase) were studied using horizontal starch-gel electrophoresis to detect multiple paternity in single litters. Only esterase-1 was found to be highly polymorphic, with four alleles in samples of both years. One litter out of 29 in 1987 and 6 litters out of 32 in 1988 contained three different paternal alleles and served as direct evidence of multiple paternity in the field. The proportion of females engaging in multiple matings in natural populations of P. leucopus, assuming that all males were involved in every multiple mating, is 25%–100% (mean 68%). Because it is unlikely that all males are involved in every multiple mating, the actual proportion of females engaging in multiple matings should be greater. Offprint requests to: X. Xia at his Canadian address     

Three-dimensional hydrodynamic and water quality model for TMDL development of Lake Fuxian, China

Lake Fuxian is the largest deep freshwater lake in China. Although its average water quality meets Class I of the China National Water Quality Standard (CNWQS), i.e., GB3838-2002, monitoring data indicate that the water quality approaches the Class II threshold in some areas. Thus it is urgent to reduce the watershed load through the total maximum daily load (TMDL) program. A three-dimensional hydrodynamic and water quality model was developed for Lake Fuxian, simulating flow circulation and pollutant fate and transport. The model development process consists of several steps, including grid generation, initial and boundary condition configurations, and model calibration processes. The model accurately reproduced the observed water surface elevation, spatiotemporal variations in temperature, and total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) concentrations, suggesting a reasonable numerical representation of the prototype system for further TMDL analyses. The TMDL was calculated using two interpretations of the water quality standards for Class I of the CNWQS based on the maximum instantaneous surface and annual average surface water concentrations. Analysis of the first scenario indicated that the TN, TP and COD loads should be reduced by 66%, 68% and 57%, respectively. Water quality was the highest priority; however, local economic development and cost feasibility for load reduction can pose significant issues. In the second interpretation, the model results showed that, under the existing conditions, the average water quality meets the Class I standard and therefore load reduction is unnecessary. Future studies are needed to conduct risk and cost assessments for realistic decision-making.