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对图表法在农学生物化学教学中的应用做了探讨,证明这种方法有助于调动学生学习的积极性、改善教学效果和提高教学质量,值得更多教师在教学实践中进行尝试。 相似文献
104.
农业科研院所科研开发模式研究 总被引:1,自引:0,他引:1
阐述了农业科研院所在科研开发过程中的发展现状,指出了其存在的主要问题:精力与经费不足,科研开发两头难以兼顾;产权制度缺陷可能导致农业科研院所背上沉重的包袱;缺乏与企业合作,低水平重复研究现象比较普遍。提出了农业科研院所科研开发模式的建议:优先考虑技术成果直接转让模式,其次推崇合作开发—技术入股模式,最后要慎用创办企业—科研生产销售一体化模式。 相似文献
105.
对林业上市公司林木资产会计信息的披露现状进行了分析,指出会计信息披露中存在明晰性不强、缺乏风险应对战略、披露过于随意等.在此基础上,对会计信息披露现存问题进行了研究,研究表明,缺乏专业人才、林木资产的特殊性、相关法规的缺失等是主要因素.最后提出了健全林业上市公司林木资产会计信息披露的相关对策,即加强政府监督、完善企业内控、推进专业人员培训等. 相似文献
106.
《Journal Of Agricultural & Food Information》2013,14(2-3):125-143
ABSTRACT Identifying the best source of information to satisfy the needs of local clientele has always been the challenge facing collection development and instruction librarians. In order to provide users with the best possible access tool and source for comprehensive information, it is important that librarians be aware of the most productive sources of information in a field. This paper identifies where the bulk of agricultural economics research is published and indexed. It also ascertains whether Google Scholar is as productive in covering this information as CAB Abstracts and EconLit. The cited reference counts for the top 50 cited sources in Web of Knowledge and Google Scholar are also compared. The scatter of the journal literature in this field, based on the Library of Congress Subject Headings, is also provided. The study identified a broad range of article scattering in areas where agricultural economics and agribusiness materials are published. On the cited reference count, Google Scholar was as productive as the Web of Knowledge. Google Scholar is a free source of very useful information for cited references and other subject searches in the area of agricultural economics and could be used to complement traditional databases. 相似文献
107.
百花山森林资源年产出价值为19 697.29万元,其中活立木价值年增长价值为3 080.65万元,占年总产出价值的15.64%,而间接使用价值,即生态价值为14 951.04万元,占年总产出的75.90%。说明百花山森林具有极高的生态效益价值,保存森林的价值,决不仅仅是木材价值的保护,更重要的应该是森林的生态效益的价值以及非消费性价值的保护。只有在生态价值不受损害的条件下,利用其他价值才是最合理的。 相似文献
108.
《Communications in Soil Science and Plant Analysis》2012,43(1-2):81-100
Abstract Differential thermogravimetry (DTG), differential scanning calorimetry (DSC), and stepwise thermogravimetry (STG), together with two acid hydrolysis methods (hydrolysis with hydrochloric acid in a single step, and hydrolysis with sulfuric acid in two steps), were evaluated to determine the quality of four plant materials (Medicago sativa, Eucalyptus globulus, Quercus ilex, and Pinus halepensis) before and after mixing with a red earth. These quality indices were then compared with the same materials in the field, whether their decomposition could be predicted. All the thermal methods gave poor results. In both DTG and DSC, the presence of the mineral matrix gave rise to strong distortions in the spectra. Since the spectrum of any mixture is not simply the sum of the spectra of the two components (organic matter + mineral matter), these distortions could not be corrected by simply subtracting the spectrum of the red earth alone. STG trials also gave poor results, because the presence of the mineral matrix greatly increased the quality indices, and reduced the ability of the method to distinguish between organic matter qualities. In view of our results, the usefulness of thermal methods in the characterization of soil organic matter would seem to be restricted to certain organic horizons (L, F, and perhaps H). In contrast, methods based on acid hydrolysis were comparatively more satisfactory. Their resolution (ability to distinguish organic matter qualities) was much higher than that of thermal methods. However, they were able to distinguish carbon more accurately than nitrogen. The sulfuric acid method, unlike the hydrochloric acid method, was affected by the presence of a mineral matrix. While both methods could be improved, in their present form they seem to operate as good predictors of carbon and nitrogen mineralization. 相似文献
109.
分析福建省莆田市涵江区农产品质量安全工作取得的成绩和存在的问题,从提升全区的农产品质量安全水平的角度,提出对策建议。 相似文献
110.
"发展经济学"创始人张培刚1945年的博士论文《农业与工业化》,是近代农业机械化理论之集大成者。由于社会和历史的原因,这一农业机械化理论宝库一直未被认真开发、应用于我国农业机械化的实践,以致走了不少弯路。随着一代经济学大师的离世,如今,挖掘、开发这一理论宝库,用之培养新型农业机械化人才,指导我国农机化实践,必将结出丰硕之果。 相似文献