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1.
桑叶配方颗粒迄今尚没有统一的质量标准。为提升桑叶配方颗粒的内在质量,对其物质基准评价方法进行了研究。选取具有代表性产地的15批桑叶制备物质基准,采用高效液相色谱法,以芦丁、异槲皮苷、紫云英苷作为评价指标,确定桑叶物质基准的出膏率范围、标志性成分含量及转移率范围,采用超高效液相色谱法,建立物质基准UPLC特征图谱,并对其主要成分进行指认。结果表明:15批物质基准中,芦丁转移率为19.94%~34.05%,异槲皮苷转移率为11.67%~43.58%,紫云英苷转移率为10.73%~43.05%;物质基准特征图谱中,标定了14个共有峰,指认出7个色谱峰,分别为新绿原酸、绿原酸、咖啡酸、芦丁、异槲皮苷、槲皮素-3-O-(6″-O-丙二酰基)-β-D-葡萄糖苷、紫云英苷。所建立的基准评价方法为桑叶配方颗粒质量标准的制定及其后续大规模生产提供了数据基础。 相似文献
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为研究石家庄市在"利剑斩污"行动管控期和非管控期挥发性有机物(VOCs)的污染特性变化,在2个时间段内对石家庄市3个国控点进行采样分析。通过苏玛罐(SUMMA罐)进行样品采集,利用气相色谱/质谱联用(GC/MS)仪对石家庄市区3个国控点的VOCs进行定性定量检测分析。结果表明,监测期间主要的特征污染物是二氯甲烷、二氯丙烷、苯和甲苯。与非管控期间相比,管控期间各污染物的质量浓度均有所降低,总VOCs平均质量浓度降低45.107μg/m~3,二氯甲烷质量浓度降低8.796μg/m~3,二氯丙烷质量浓度降低3.750μg/m~3,苯质量浓度降低18.285μg/m~3,甲苯质量浓度降低16.895μg/m~3。大气环境调控策略的实施,有效降低了VOCs浓度,减少了空气污染程度,空气质量改善效果显著。"利剑斩污"行动期间采取的相关举措,对于制定常态化下VOCs的防治对策具有一定的参考价值。 相似文献
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This study uses longitudinal data and four different measures of mental health to tease out the impact of psychiatric disorder onsets and recoveries on employment outcomes. Results suggest that developing a mental health problem leads to a significant increase in the probability of transitioning to non-employment, while a recovery increases the probability of return to work among the not employed with a mental health problem. No consistent effect was found on hours worked and earnings. Research and policy attention is needed with respect to early interventions such as job retention programmes to help workers with mental health problems remain employed as well as interventions that may lead to recovery and return to work. More research is needed especially with data and models that can differentiate between the effects of mental health onsets and recoveries on employment exit and return to work transitions. 相似文献
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Edward J. Nell 《Review of Political Economy》2016,28(3):448-463
To begin with, we'd like to express our appreciation to our three commentators for their thoughtful and helpful reviews. Like the founders of the subject, we believe, and our reviewers seem to agree, that structural econometrics has the potential to enable us to develop serious working models of how different economies actually operate, and also to tell us something about the changing patterns of their growth and transformation. But both we and our reviewers agree that there is a great deal wrong with the way econometrics is practiced today. 相似文献
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根据笔者在实验室长期工作的经验,结合实验室的相关标准,按量值溯源的管理途径,进一步阐述了实验室充分运用量值溯源信息,对仪器设备和标准物质进行科学管理的具体方法和措施,为不断提高检测工作质量提供了有力的保证。 相似文献
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Elizabeth H. Weybright Linda L. Caldwell Nilam Ram Edward A. Smith Lisa Wegner 《Leisure Sciences: An Interdisciplinary Journal》2013,35(4):311-331
Reducing adolescent substance use is important in South Africa, a developing nation with increasing adolescent substance use, lack of leisure/recreation opportunities, and high rates of adolescent discretionary time. Previous research suggests leisure boredom and adolescent substance use co-occur in this setting. Using longitudinal data from 2,580 South African adolescents as they progressed from the 8th to 11th grade, the current study disentangles the associations of trait and state leisure boredom with substance use, and examines how ability to restructure boring situations moderates those associations. On average, individuals with higher trait boredom used more substances, and on occasions when state boredom was high, the prototypical adolescent used more substances. Although restructuring did not moderate these associations, greater ability was associated with lower substance use independent of leisure boredom. Findings illustrated the importance of considering how trait and state aspects of leisure may contribute to adolescents’ risk behavior and addressed through preventive intervention. 相似文献
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社会冲突分为实体性冲突和程序性冲突两种。解决社会冲突的途径有当事人之间的和解、第三者的调解、当事人的申诉,仲裁机构的仲裁及法院的诉讼等。在这诸多的途径中,司法诉讼是终级途径。司法改革应扫除一切阻碍司法解决争端的障碍,将司法至上真正化为立法和司法的语言。 相似文献
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随着医疗技术的持续进步,对卫生服务的产出进行质量调整愈发重要。目前,卫生服务产出的质量调整仍旧处在中国的国民经济核算框架之外,中国还没有卫生服务产出质量调整的理想指标。因此,如何将质量调整指标引入中国的国民经济核算还需要进一步研究。 相似文献