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461.
当前,中国正处于城市化高速发展时期,城市规划在生态城市建设过程中起着非常重要的作用。本研究目的:探讨城市规划中的生态建设方法,并对增城市城市规划中的生态建设实践进行思考,为科学引导增城市社会、经济、文化、生态协调发展提供参考。研究方法:案例研究法,时间序列分析法和比较研究法相结合。研究结果:增城市生态建设得益于准确科学的规划控制引导,基于时代发展的制度设计和规划保障是增城市取得生态建设重大成果的根本原因。研究结论:城市规划中的生态建设是城市发展的重要命题,是实现人与自然和谐共存的基础,是实现工业文明向生态文明转变的根本保证。  相似文献   
462.
本文主要介绍了处理跨断层水准数据的2种方法,包括断层垂直形变速率合成分析法和断层形变趋势累计率分析法。文中概括了各种方法的特征以及在分析苏鲁皖地区断层活动趋势中的应用。  相似文献   
463.
Ordered mesoporous carbon supported iron catalysts(Fe/OMC) were prepared by the incipient wetness impregnation method and investigated in Fenton-like degradation of 4-chlorophenol(4CP) in this work. XRD and TEM characterization showed that the iron oxides were well dispersed on the OMC support and grew bigger with the increasing calcination temperature. The catalyst prepared with a lower calcination temperature showed higher decomposition efficiency towards 4CP and H2O2, but more metals were leached. The effect of different operational parameters such as initial pH, H2O2 dosage, and reaction temperature on the catalytic activity was evaluated. The results showed that 96.1% of 4CP and 47.4% of TOC was removed after 270 min at 30°C, initial pH of 3 and 6.6 mmol/L H2O2. 88% of 4CP removal efficiency was retained after three successive runs, indicating Fe/OMC a stable catalyst for Fenton reaction. 4CP was degraded predominately by the attack of hydroxyl radical formed on the catalyst surface and in the bulk solution due to iron leaching. Based on the degradation intermediates detected by high performance liquid chromatography, possible oxidation pathways were proposed during the 4CP degradation.  相似文献   
464.
Sulfate, nitrate and ammonium(SNA) are the dominant species in secondary inorganic aerosol, and are considered an important factor in regional haze formation. Size-fractionated aerosol particles for a whole year were collected to study the size distribution of SNA as well as their chemical species in Shanghai. SNA mainly accumulated in fine particles and the highest average ratio of SNA to particulate matter(PM) was observed to be 47% in the fine size fraction(0.49–0.95 μm). Higher sulfur oxidation ratio and nitrogen oxidation ratio values were observed in PM of fine size less than 0.95 μm. Ion balance calculations indicated that more secondary sulfate and nitrate would be generated in PM of fine size(0.49–0.95 μm). Sulfur K-edge X-ray absorption near-edge structure(XANES) spectra of typical samples were analyzed. Results revealed that sulfur mainly existed as sulfate with a proportion(atomic basis) more than 73% in all size of PM and even higher at 90% in fine particles. Sulfate mainly existed as(NH4)2SO4 and gypsum in PM of Shanghai. Compared to non-haze days, a dramatic increase of(NH4)2SO4 content was found in fine particles on haze days only, which suggested the promoting impact of(NH4)2SO4 on haze formation. According to the result of air mass backward trajectory analysis, more(NH4)2SO4 would be generated during the periods of air mass stagnation. Based on XANES, analysis of sulfate species in size-fractionated aerosol particles can be an effective way to evaluate the impact of sulfate aerosols on regional haze formation.  相似文献   
465.
财务危机是威胁企业持续经营的根本性危机,它不是突然而至,分为潜伏期、爆发期、成长期和解决期四个阶段逐步积累过程.根据不同阶段的企业财务状况,把爱德华.阿特曼Z值计分模型和不同时期的相关财务指标结合起来,运用定量和定性相结合的分析方法,判断分析企业的财务危机的级别,从而采取相应的措施,以利于规避财务风险.  相似文献   
466.
Every year nearly 6 percent of children worldwide are born with a serious congenital malformation, resulting in death or lifelong disability. In the United States, birth defects remain one of the leading causes of infant mortality. Among the common structural congenital defects are conditions known as neural tube defects (NTDs). These are a class of malformation of the brain and spinal cord where the neural tube fails to close during the neurulation. Although NTDs remain among the most pervasive and debilitating of all human developmental anomalies, there is insufficient understanding of their etiology. Previous studies have proposed that complex birth defects like NTDs are likely omnigenic, involving interconnected gene regulatory networks with associated signals throughout the genome. Advances in technologies have allowed researchers to more critically investigate regulatory gene networks in ever increasing detail, informing our understanding of the genetic basis of NTDs. Employing a systematic analysis of these complex birth defects using massively parallel DNA sequencing with stringent bioinformatic algorithms, it is possible to approach a greater level of understanding of the genomic architecture underlying NTDs. Herein, we present a brief overview of different approaches undertaken in our laboratory to dissect out the genetics of susceptibility to NTDs. This involves the use of mouse models to identify candidate genes, as well as large scale whole genome/whole exome (WGS/WES) studies to interrogate the genomic landscape of NTDs. The goal of this research is to elucidate the gene-environment interactions contributing to NTDs, thus encouraging global research efforts in their prevention.  相似文献   
467.
To analyze current policies on cultivated land protection, this article discusses the application of transferable development rights in cultivated land protection by examining the connotation, operation mechanism, and construction on the market mechanism, benefits driving forces, and expected benefits. The results suggest that economic incentives and fairness have been neglected in previous policies on cultivated land protection. Moreover, the introduction of transferable development rights can not only eliminate the imbalance of interests, but also enhance the incentives for farmers and developers. In addition, it can significantly reduce the fiscal expenditure of the government.  相似文献   
468.
针对铁路的特点和铁路安全工作的难度以及近两年进行安全基础整顿和建设的经验表明,安全工作仍难以有序可控的不断改进,通过对安全文化的认识和探讨,提出要取得铁路运输安全工作的突破,必须全面加速安全文化建设。加速安全文化建设的前提是加快体制建设,其关键是加快安全机制建设,其保证是加快安全法制建设,其核心是加快干部、工人队伍的安全文化素质提高,其重要方法是加强对全社会的安全知识教育。  相似文献   
469.
In this paper we describe a new incentive-based pollution control program in China, in which the environmental performance of firms is rated from best to worst using five colors--green, blue, yellow, red and black--and the ratings are disseminated to the public through the media. We focus on the first two municipal disclosure programs, which have been implemented at very different levels of economic and institutional development. In both cases, the increases in compliance with pollution regulations have been similar to increases produced by public disclosure programs in Indonesia, the Philippines, and Vietnam. The results suggest that incentives created by public disclosure may significantly reduce pollution in China, even though environmental NGO's play little role and there is no formal channel for public participation in environmental regulation.  相似文献   
470.
资源开发利用与可持续发展问题探讨   总被引:2,自引:0,他引:2  
本文在简介资源系统与资源开发概念的基础上,提出了资源开发的原则,并结合我国资源开发的限制因素,提出了开发措施。  相似文献   
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