高校毕业生结构性失衡问题探讨

高校毕业生结构性失衡是指随着我国经济结构的变化，毕业生的供给结构与需求结构不协调。通过高校毕业生结构性失衡的实证分析，本文觉得其症结主要是高等教育层次结构和科类结构的失衡。这在很大程度上决定毕业生资源的供给结构，因此，高等教育结构的调整是解决高校毕业生结构性失衡关键。     

土壤中裂隙与其它类型孔隙结构差异的图像比较

裂隙是孔隙的一类。文章利用土壤切片的数字图像,采用目视分离的方法,比较研究了裂隙与其它类型的孔隙在结构上的差异、选择的土样研究结果表明,目视分离裂隙的方法是可行的,土体中的裂隙直径分布曲线是不规则的,而其它类型的孔隙直径分布曲线则类似对数正态分布;土壤总孔隙中直径较大的部分主要由裂隙构成,直径较小的部分则由其它类型孔隙和裂隙共同构成;土壤表面裂隙与土体内部裂隙在结构上可能具有一定差异。     

村级农业生态经济系统的结构调控研究--以石辛庄为例

运用生态学原理,从结构元、结构链和结构网3个层次对石辛庄村级农业生态经济系统结构进行调控,并从生态效益、资源利用效益、环境效益和经济效益4个方面对该生态经济系统的调控效果作了评价.     

Comparative study of 15 lysosomal enzymes in chorionic villi and cultured amniotic fluid cells. Early prenatal diagnosis in seven pregnancies at risk for lysosomal storage diseases

A large number of chorionic villi samples obtained from women undergoing elective first trimester termination of pregnancy was analysed by enzyme assays similar to those applied to cultured amniotic cells. The levels of 15 lysosomal enzymes were compared to those observed in tissue cultures of amniotic cells obtained through amniocentesis at 16-18 weeks of pregnancy and the results were discussed in order to assess the usefulness of trophoblast biopsy for first trimester diagnosis of hereditary lysosomal diseases. The data suggest the applicability of this source of fetal cells for prenatal diagnosis of fifteen respective genetically determined enzyme deficiencies with the probable exception of α-L -iduronidase deficiency. Enzyme determinations were performed on chorionic villi samples of two pregnancies at risk for Tay-Sachs disease, three pregnancies for GM₁ gangliosidosis type 1, one for mucopolysaccharidosis type VI and one for Wolman's disease.     

多氯联苯复合污染土壤的微生物群落结构多样性变化

土壤微生物群落结构多样性是指示土壤生态系统稳定性及其功能的重要传感器。采用磷脂脂肪酸(Phospholipid fatty acids,PLFAs)方法,对长江三角洲地区某POPs高风险区PCBs长期复合污染土壤的微生物群落结构多样性进行了初步研究。结果表明,PCBs重度污染土壤中格兰氏阴性菌(16:1w9、cy17:0等)和厌氧微生物(18:1w7)的PLFAs组分含量较多,而格兰氏阳性菌(如i15:0、i17:0等)、放线菌(16:0(10Me))及真菌(18:2ω6,9)和好氧性微生物的PLFAs含量较低,表明PCBs污染土壤中微生物群落结构与组成发生了明显变化。这一结果为PCBs降解微生物资源的定向筛选提供了科学依据。     

华北平原地下热水矿床分布规律及形成

我国华北平原分布有大小不等、形状各异的地下热水矿床;赋存于石灰岩地层形成的地质构造凸起部位的地下热水富水性好,井产水量大,自喷能力强,水质好,矿化度低,温度高,具有较高的开发利用价值。华北平原地下热水的热源与第三纪侵入的火成岩无关。地下热水的补给来源是山区大气降水渗入地下经过较大的构造断裂带和碳酸盐岩地层岩溶溶洞、断裂裂隙深循环以后形成的。地下热水的温度主要取决于水循环的深度。     

基于ISM的油港集疏运作业安全风险分析

油港集疏运作业安全对油港运营安全管理至关重要。通过实地调研、访谈及问卷调查确定了油港集疏运作业安全风险因素;分析各因素间的直接影响关系,建立邻接矩阵和可达矩阵,构建了油港集疏运作业安全影响因素的解释结构模型;通过不同层级之间的关系分析,找出了油港集疏运作业过程中优先级较高的风险因素。结果表明,表层风险因素多为设备因素,中层风险因素集中于港内自身和港外环境因素,深层风险因素主要为人为因素和安全管理因素。     

中国海岸地带面临的重大环境变化与灾害及其防御对策

中国海岸地带面向２１世纪的持续发展,面临着相对海面加速上升和热带气旋、风暴潮与低洼地洪涝不断加剧以及海岸环境急剧恶化等一系列重大环境变化与灾害问题。本文着重分析相对海面上升、热带气旋、风暴潮与洪水灾害以及海岸环境污染的特征、演变趋势及防御对策。     

Anthropogenic-driven changes with focus on the coastal zone of Mauritius, south-western Indian Ocean

Some 44% of the world's population lives within 150 km of the coast and mass migration towards the coast will continue in the decades ahead. Degrading and exhaustive uses of land, water and other coastal resources and disruption of environmental processes through degradation of environmental quality and loss of critical terrestrial and aquatic habitats can lead to serious deleterious impacts on the health and productivity of coastal ecosystems. Following the Arusha Resolution (1993), the Seychelles Statement (1996) and the Colombo CZM Workshop (1999), the need for integrated coastal zone management has become critical because of the limited land resources and unproportional domination of coastal areas in the wider Caribbean and Indian Ocean/ Pacific island states. The coastal zone of Mauritius (1,850 km², 20°S, 58°E, south-western Indian Ocean, 1.12 million inhabitants) was redefined in 1997 in the Environmental Protection Act of 1991 [Part VII (Act 34)] to include all islets within the Exclusive Economic Zone (EEZ; 1.7 million km²). During the 1980s, the Mauritian economy underwent major structural changes successfully, with a rapid phase of industrialization diversifying into two major activities, textiles and tourism. Existing reports and data in a common framework have to be synthesized and organized to fill existing gaps in knowledge with data collection and scientific inquiries, to identify social and economic drivers and to relate socioeconomic change to demands for environmental resources (land use, water resources, marine systems) and environmental impacts as proposed under the MERMAID (Mauritius Environmental Resource Management and Industrial Development) project. Nutrient flux and sediment trace metal contamination studies are currently underway to investigate different watersheds impacted by agricultural, urban and industrial activities in the north-west of the island. There is a pressing need to integrate the natural sciences with socioeconomic disciplines as proposed by the International Human Dimensions Program (IHDP) for an integrated management of coastal zones. Three integrated pilot projects in the Pacific-Indian Ocean and wider Caribbean as identified by Land Ocean Interaction in the Coastal Zone (LOICZ) in the future, including current status and changes in material fluxes from drainage basins, transboundary impacts from the ocean and atmospheric inputs, could elucidate the land–sea interactions and human dimensions of change on small islands. The sustainability of marine resources and the conservation of biological diversity will depend on a critical understanding of linkages between human activities and ecological responses and upon a citizenry that assumes ownership of these regions. Case studies would also help in investigating how humans affect transport pathways and biogeochemical cycles in small island states. Electronic Publication