Diversification and Sustainable Development in Chinese Agriculture

Feeding a growing population exceeding 1 billion is a big challenge to the Chinese government and has partly led to the self-sufficient policy in grain production and supply for decades. However, the efforts to push grain production everywhere have resulted in not only deterioration of the environment but also stagnation or even reduction in farmers' income as production costs continue to increase. This situation might be worsening after China's accession to the WTO that provides market access for bulk commodity imports. A sustainable development in Chinese agriculture depends on diversification, or structural adjustment, that allows Chinese farmers to fully utilize their comparative advantage in production of labor-intensive goods. Past experience has shown that diversification has contributed more than a half of the growth in Chinese agriculture during the reform period and reduced stresses on the environment at the same time. It is likely to contribute even more to Chinese agriculture in the future an     

碳同位素在油气地质研究中的应用和进展

稳定同位素地球化学是发展较快的学科之一，七十年代起被广泛应用于油气地球化学研究中。本文综述了碳稳定同位素在油气地质研究中的应用和进展，这些应用主要包括确定源油的形成环境与形成时代；进行油／油、油／源对比；判别天然气的成因类型并进行对比；判断天然气的成熟度。     

室内空气污染及防治对策

从室内空气污染的来源入手，分析了目前我国室内空气质量控制存在的主要问题，针对我国国情，从社会、经济、技术角度提出目前我国室内空气污染防治应首先着手解决实际问题和今后将要实施的行政管理策略及技术防治策略。     

FHD-1型质子磁力仪的改进与完善

根据FHD 1型质子磁力仪在实际使用过程中存在的一些问题 ,以及一些用户提出的建议和要求 ,对FHD 1型质子磁力仪的实时时钟、标定方法、通用性与适应性、抗干扰能力方面进行了改进和完善 ,本文对此作介绍。     

Reactions to psychological contract breach: a dual perspective

This study examined reactions to psychological contract breach from two separate perspectives, that is, employee's reactions to perceptions of employer breach and supervisor's reactions to perceptions of employee breach of the psychological contract. In addition to the main effects, we also hypothesized that the benevolence (or kindness) of the supervisor and the traditional values (or respect for authority) of the employee would attenuate the negative effects of psychological contract breach. We tested these hypotheses with a sample of 273 supervisor‐subordinate dyads from the People's Republic of China. The results showed that employer breach correlated negatively with employee outcomes of organizational commitment (OC), organizational citizenship behavior (OCB), and work performance, but this negative relationship was weaker for employees with traditional values. The results also demonstrated that employee breach correlated negatively with responses from the supervisor, in terms of the mentoring provided to the employee and the leader‐member exchange (LMX) quality. However, more benevolent supervisors reacted less negatively in terms of the mentoring than did the less benevolent supervisors. Implications for future research are offered. Copyright © 2007 John Wiley & Sons, Ltd.     

石灰石与SO_2直接硫酸化反应宏观动力学的研究

温度、ＳＯ＿２浓度、颗粒大小、石灰石类型和样品的微观结构影响着直接硫酸化反应过程。这一反应过程能用缩芯模型来描述，并对ＳＯ＿２具有一级反应特征。本征反应和产物层扩散控制反应的活化能分别是８５．２ｋＪ／ｍｏｌ和４１．５ｋＪ／ｍｏｌ。在８００℃、２０００ｐｐｍＳＯ＿２和反应１０１ｍｉｎ的条件下，Ｉｇｚｌａｂｅｒｇａ和Ｆｏｒｓｂｙ石灰石的ＣａＣＯ＿３转化率分别可达８４％和７２％。在初始２ｍｉｎ内已煅烧石灰石（ＣａＯ）的硫酸化反应速率与石灰石的反应速率稍高，随后二者基本相同。     

渗铝温度/时间对镍基高温合金的渗层形成影响规律

目的提高材料的高温抗氧化腐蚀性能。方法采用气相渗铝方法在K417镍基高温合金表面制备铝化物涂层,通过光学显微镜、扫描电子显微镜(SEM)和能谱(EDS)分析渗铝层厚度、显微组织形貌和各元素在渗层中的分布,分析温度和时间对镍基高温合金渗铝层的形成影响规律。结果气相渗铝方法制备的渗铝层组织为典型的外扩散型组织即外层是单一的β-NiAl相,内层是含富Cr析出相的扩散层,扩散层的细小析出相对Al元素的扩散起到阻碍作用。结论随着渗铝温度的提高和渗铝时间的延长,渗层厚度逐渐增加,且渗铝温度对渗层厚度的影响远高于渗铝时间对渗层深度的影响。渗铝温度临界值为980℃,低于该温度时厚度增长不显著,高于该温度时厚度对渗铝温度和时间的敏感性增加。此外,渗铝温度越高,渗铝层组织中形成孔洞的倾向越大。     

燃烧温度对柴油固体颗粒物形貌及氧化特性影响的试验研究

依据柴油机缸内的燃烧环境状态,采用TF-1200X管式炉,采集了柴油在不同温度条件下燃烧产生的颗粒物.应用扫描电镜SEM、X射线衍射仪和热重分析仪,对不同燃烧温度下颗粒的平均粒径、计盒维数、元素质量分数、颗粒表面氧化活性等变化规律进行了研究.结果表明:燃烧温度介于523～623 K之间时,柴油燃烧形成的固体颗粒物主要由颗粒状焦组成,呈片状和珠串状,颗粒中的C元素质量分数随燃烧温度的增加而增加,颗粒着火温度、活化能随燃烧温度的增加而降低;燃烧温度大于723 K时,颗粒呈球状和团簇状,平均粒径随温度的增加而减小,颗粒的C元素质量分数、计盒维数及活化能随燃烧温度的增加而增加,颗粒着火温度随燃烧温度的增加呈上升趋势;柴油在523～923 K之间燃烧形成的颗粒物,随着热重氛围气中氧体积分数的增加,颗粒氧化放热速率增加,活化能变化不大.     

兰炭生产过程中固体废物的产生与利用现状分析

在对国内兰炭生产工艺流程应用及现状介绍的基础上,概括总结了旧式低温干馏阶段和现阶段兰炭生产过程中固体废物的产生节点、种类、性质和主要处置方式。结果表明,旧式低温干馏阶段,兰炭生产过程中产生的固体废物主要包括煤筛分破碎工序产生的末煤和煤矸石、筛焦工序产生的焦粉、焦油冷却收集系统产生的焦油渣等;现阶段,兰炭生产过程中产生的固体废物主要包括煤筛分破碎工序产生的末煤和煤矸石以及破碎过程中经除尘器收集的煤尘、筛焦工序产生的焦粉、废水处理污泥、焦油冷却收集系统产生的焦油渣、脱硫工序产生的脱硫残液等。其中末煤、煤矸石、煤尘、焦粉作为一般工业固废全部综合利用,废水污泥、焦油渣、脱硫残液主要掺入原料煤中自行消化处置。