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1.
在水资源约束趋紧的背景下,选取长江三角洲城市群中26个城市2005~2014年的面板数据,运用SBM模型对工业用水效率进行测算,并基于可分解的泰尔指数分析长江三角洲城市群内部工业用水效率的空间差异。结果显示:(1)长江三角洲城市群工业用水效率水平整体偏低,在不考虑与考虑非期望产出的情况下,工业用水效率10a平均值分别为 0.591 8.和 0.519 7;(2)工业用水效率的地区内部差异是造成总差异的主要部分,并且有随时间递增的趋势,其中安徽省对于地区内部差异的贡献率最大,其次为浙江省,江苏省贡献率最低;(3)江苏省各城市工业用水效率虽然差异不大但整体水平较低,而上海市工业用水效率较高并处于稳步上升状态。因此,缩小地区内部差异是实现长江三角洲城市群工业用水效率整体上升的重要途径。  相似文献   
2.
以重金属铜离子为研究对象,设计了包含黏土防护层、壤土运移层、竹炭(碳粉)净化层组成的复杂室内大土柱(直径Φ=280 mm)模型。在重金属铜离子运移试验研究的基础上,着重分析了铜离子在具有复杂分层结构土柱模型中的迁移规律。结果表明,黏土对铜离子的吸附阻滞作用显著高于壤土,阻滞效率在91%左右。经黏土阻滞后,碳粉净化层与壤土层自净效率约占7.5%,显著降低了模型出口铜离子残余量(可降至总量的0.45%)。对设计研究模型,试验结果充分体现出黏土吸附阻滞作用为主、碳粉净化作用为辅的显著特性。因此,如将此理念推广至地下水环境保护实践,则可简称之为"以防为主,以治为辅"的地下水环境保护理念。  相似文献   
3.
Environmental Science and Pollution Research - Drinking water containing environmental endocrine disruptor compounds (EDCs) endangers human health, and researching the purification process of...  相似文献   
4.
Environmental Science and Pollution Research - The new severe acute respiratory syndrome coronavirus 2 was initially discovered at the end of 2019 in Wuhan City in China and has caused one of the...  相似文献   
5.
• Fe(III) accepted the most electrons from organics, followed by NO3, SO42‒, and O2. • The electrons accepted by SO42‒ could be stored in the solid AVS, FeS2-S, and S0. • The autotrophic denitrification driven by solid S had two-phase characteristics. • A conceptual model involving electron acceptance, storage, and donation was built. • S cycle transferred electrons between organics and NO3 with an efficiency of 15%. A constructed wetland microcosm was employed to investigate the sulfur cycle-mediated electron transfer between carbon and nitrate. Sulfate accepted electrons from organics at the average rate of 0.84 mol/(m3·d) through sulfate reduction, which accounted for 20.0% of the electron input rate. The remainder of the electrons derived from organics were accepted by dissolved oxygen (2.6%), nitrate (26.8%), and iron(III) (39.9%). The sulfide produced from sulfate reduction was transformed into acid-volatile sulfide, pyrite, and elemental sulfur, which were deposited in the substratum, storing electrons in the microcosm at the average rate of 0.52 mol/(m3·d). In the presence of nitrate, the acid-volatile and elemental sulfur were oxidized to sulfate, donating electrons at the average rate of 0.14 mol/(m3·d) and driving autotrophic denitrification at the average rate of 0.30 g N/(m3·d). The overall electron transfer efficiency of the sulfur cycle for autotrophic denitrification was 15.3%. A mass balance assessment indicated that approximately 50% of the input sulfur was discharged from the microcosm, and the remainder was removed through deposition (49%) and plant uptake (1%). Dominant sulfate-reducing (i.e., Desulfovirga, Desulforhopalus, Desulfatitalea, and Desulfatirhabdium) and sulfur-oxidizing bacteria (i.e., Thiohalobacter, Thiobacillus, Sulfuritalea, and Sulfurisoma), which jointly fulfilled a sustainable sulfur cycle, were identified. These results improved understanding of electron transfers among carbon, nitrogen, and sulfur cycles in constructed wetlands, and are of engineering significance.  相似文献   
6.
废铅酸蓄电池具有一定的回收价值,但生产过程和回收过程都容易造成污染。为了引导企业对废旧电池进行正确处理,也为了防止环境被破坏,必须采取科学合理的技术和工艺,并遵循国家相关政策,本文就对此进行了分析,希望能给相关工作提供借鉴。  相似文献   
7.
在《瑞典环境法典》编纂之前,其《环境保护法》存在诸多问题,如:指导性不强、威慑力不足、过于抽象、各环境法律法规之间存在重叠与冲突等,为了使环境领域的立法实现体系化并促进可持续发展,瑞典开始编纂《环境法典》。《瑞典环境法典》采取适度法典化的编纂模式,在编纂过程中注重本土化和国际化的有效结合,最后形成"以法典法为主,辅之以单行法"的环境法律体系。通过对瑞典环境法法典化的特点及原因进行深入研究,并结合我国环境保护领域的立法现状可以得知,我国环境立法应采取适度法典化的立法模式:编纂环境法典应分阶段进行,而不是一蹴而就;应以形式化法律汇编作为起点,逐步向实质性法典编纂迈进。此外,还要加强环境法典编纂的理论研究为法典编纂提供充足的理论支撑。  相似文献   
8.
A systematic understanding of dynamic animal extinction trajectories for different regions in a nation like China is critically important to developing practical conservation strategies. We explored historical and contemporary changes in terrestrial mammalian diversity to determine how diversity in each of the 5 regions in China has changed over time and to examine the conservation potential of these regions. We used records from databases on Pleistocene mammalian fossils and historical distribution records (1175–2020) for Primates (as a case study) to reconstruct evolutionary and historical distribution trajectories of the 11 orders of terrestrial mammals and to predict their prospective survival based on the national conservation strategy applied. The results indicated that since the Pleistocene, 4–5 mammalian orders have been lost in the northeast, 3 in central China, 2 along the coast, and 1 in the northwest. In the southwest, all 11 orders were maintained. Contemporarily, the coast and southwest had the highest and second-highest species densities. The southwest region and southeastern sections of the northwest region were the most historically and contemporarily diverse areas, which suggests that they should be the first priority for protected area (PA) designation. The central and coastal areas should be secondarily prioritized. In these 2 regions, conservation should focus on human coexistence with nature. Less attention should be paid to the PA in the northeast and western northwest because in these areas ecosystems are depauperate and the climate is harsh. Conservation in these areas should focus principally on avoiding further human encroachment on natural areas. Article impact statement: Historical and contemporary patterns of extinction can be a basis for mammalian conservation strategies.  相似文献   
9.
The annual relative mass of storage organs cycle of Bufo gargarizans in southwestern China was studied from December 2005 to November 2006. We described how those organs changed in response to extreme temperatures. Energy reservation dropped to the lowest levels after dormancy for both sexes, and then increased for period of 4.25 month. However, the mass of these organs dropped again rapidly until August (liver) and September (fat bodies) due to the constraint from extreme high temperature occurred during the summer, and then non-significantly increased before hibernation. For ovaries, varied with a different profile to those of liver and fat bodies have a resting period of four months. In addition, the toads’ ovaries kept growing when the mass of liver and fat bodies declining accordingly during hibernation. Therefore, ovarian mass increased during the hibernation and non-hibernation period.  相似文献   
10.
为研究深孔预裂爆破技术在含坚硬顶板高瓦斯煤层开采中的应用,以顾桥矿1123(1)工作面坚硬顶板为研究对象,基于小挠度理论建立了坚硬顶板垮落力学模型,导出了初次来压步距计算式;综合考虑瓦斯抽采需要,对深孔预裂爆破孔进行了优化设计,并在工作面顶板中开展了现场试验研究。结果表明:在工作面推进至27.3m时出现垮落,爆破后钻孔瓦斯流量显著增加,部分提高至30倍以上,瓦斯抽采量提高了3.5倍,初采期间安全回采煤炭25万吨,实现了坚硬顶板控制和卸压增透双重作用。  相似文献   
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