成都区域管制中心电磁辐射环境影响分析与防护措施

文章分析了成都区域管制中心内的雷达、微波通信站、遥控台和卫星地面站等典型电磁设施的电磁辐射污染源状况,用电磁辐射分析仪对拟建成都区域管制中心及机场等典型环境中的电磁辐射水平开展了监测与评价,有针对性地提出了电磁辐射防护措施,为合理建设成都区域管制中心提供了辐射环境方面的科学依据。     

加油站分散式油气回收工艺的研究

针对加油站油品蒸发损耗及降耗工艺应用问题,提出新的油库与加油站＂分散式油气回收工艺＂,建立了其经济模型,推导出系统的计算公式,并就某城市加油站分散式油气回收系统进行了具体的经济评价计算。并将计算结果同传统的加油站油气回收系统的经济计算结果进行了比较,比较结果表明：分散式油气回收工艺较传统的加油站油气回收系统具有更好的经...     

一种计量青鳉鱼胸鳍和尾鳍摆动频率和幅值的计算机视觉算法

青鳉鱼在饮用水安全领域具有很高的应用价值,其鱼鳍的活动状态可以反映水质的污染状况。但由于技术条件的限制,传统的方法无法实时而有效地提取到这些特征。针对这个问题,提出了一种可以高效识别并测量青鳉鱼胸、尾鳍摆动频率和幅值的计算机视觉算法。其中,为了快速地提取到这2个细节,自动阈值分割、帧差法、背景差分法、重心法、图像卷积和骨架细化等耗时极短的图像处理方法被应用到这项研究当中。初步试验显示这种算法在应用过程中是高效而可行的。它可以被广泛地应用到水环境监测领域,如研究有毒物质对青鳉鱼行为特性的影响和评估水环境的危险程度。     

Nanostructured semiconducting materials for efficient hydrogen generation

Massive production of hydrogen by water decomposition triggered by a solar light active photocatalyst is a major objective in chemistry and a promising avenue to overcome the global energy crisis. The development of efficient, stable, economically viable and eco-friendly photocatalysts for hydrogen production is a challenging task. This article reviews the use of nanocomposite in three combinations: metal oxide–metal oxide semiconductor, metal–metal oxide semiconductor and metal chalcogenide–metal oxide core–shell nanostructures. These core–shell structures occur in two forms: a simple form where the photocatalyst is either in the core or the shell or in a more complex system where the core–shell structure comprises a co-catalyst deposited on a semiconducting material. We discuss the design, synthesis and development of semiconductor-based nanocomposite photocatalysts for hydrogen production. The major points are the role of catalytic active sites, the chemical nature of sacrificial agents, the effect of light sources, the variable light intensity and the energy efficiency calculation. For TiO₂-based nanocomposites, the metal oxide or metal co-catalyst loading of 1.0–3.0 wt% was optimal. TiO₂ nanotube–CuO hybrid nanocomposites produce 1,14,000 µmol h^?1 \({\text{g}}^{ - 1}_{\text{cat}}\), whereas TiO₂/Au nanocomposites display 1,60,000 µmol h^?1 \({\text{g}}^{ - 1}_{\text{cat}}\). For core–shell catalysts, a shell thickness of 2–20 nm was found for the best activity, and its performance is as follows: (a) CdS–NiO system produces around 19,949 µmol h^?1 \({\text{g}}^{ - 1}_{\text{cat}}\) and (b) CuO–Cr₂O₃ as co-catalyst immobilized on TiO₂ system produces around 82,390 µmol h^?1 \({\text{g}}^{ - 1}_{\text{cat}}\).     

Crop damage and livestock depredation by wildlife: a case study from Nanda Devi Biosphere Reserve,India

The success of conserving biological resources in any Biosphere Reserve or protected area depends on the extent of support and positive attitudes and perceptions of local people have towards such establishments. Ignoring the dependence of the local people for their subsistence needs on resources of such areas leads to conflicts between protected area managers and the local inhabitants. Crop yield losses and livestock depredation were serious problems observed in most buffer zone villages of Nanda Devi Biosphere Reserve. In the present study 10 villages situated in the buffer zone of Nanada Devi Biosphere Reserve (1612 km2 area) in Chamoli district of Uttaranchal, India were studied during 1996-97 using a questionnaire survey of each household (419 = households; 2253 = total population in 1991; 273 ha = cultivated area). Estimates of crop yield losses were made using paired plots technique in four representative villages for each crop species. The magnitude of crop yield losses varied significantly with the distance of agricultural field from forest boundary. The total crop yield losses were high for wheat and potato in all the villages. The spatial distribution of total crop yield losses in any village indicated that they were highest in the area near to forest and least in the area near to village for all crops. Losses from areas near to forest contributed to more than 50% of total losses for each crop in all villages. However, in Lata, Peng and Tolma villages, the losses are high for kidney bean and chemmi (local variety of kidney bean) which varied between 18.5% to 30% of total losses in those villages. Potato alone represents 43.6% of total crop yield loss due to wildlife in Dronagiri village in monetary terms. Among the crops, the monetary value of yield losses are least for amaranth and highest for kidney bean. The projected total value of crop yield losses due to wildlife damage for buffer zone villages located in Garhwal Himalaya is about Rs. 538,620 (US$ 15,389). Besides food grains, horticultural crops i.e. apple, also suffered maximum damage. Major wildlife agents responsible for crop damage were wild boar, bear, porcupine, monkey, musk deer and partridge (chokor). Monkey and wild boar alone accounted for about 50% to 60% of total crop damage in the study villages. Goat and sheep are the major livestock killed by leopard. The total value of livestock losses at prevailing market rates is about Rs. 1,024,520 (US$ 29,272) in the study villages. Due to existing conservation policies and laxity in implementation of preventive measures, the problems for local inhabitants are increasing. Potential solutions discussed emphasize the need to undertake suitable and appropriate protective measures to minimize the crop losses. Change in cropping and crop composition, particularly cultivation of medicinal plants (high value low volume crops), were also suggested. Besides, fair and quick disbursement of compensation for crop loss and livestock killing need to be adopted. Local people of the buffer zone area already have a negative attitude towards park/reserve establishment due to socio-political changes inducing major economic losses and this attitude may lead to clashes and confrontations if proper ameliorative measures are not taken immediately.     

稀土湿法冶炼废水处理与资源化研究

对某稀土湿法冶炼工艺进行了以清洁生产为核心的技改方案研究,在清洁工艺设计的基础上,通过工艺原理分析和试验,说明其革新工艺的经济有效性;从酸浸废液中年回收硫酸亚铁３０００ｔ,从碱转废液中年回收硫酸钠３０００ｔ;从废水回收冰晶石,氟回收８６％;     

Holistic correlation of world’s largest social safety net and its outcomes with Sustainable Development Goals

The five largest social safety net (SSN) programmes in the world are being implemented in India, China and Brazil. Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) is one of these programmes and regarded as the world’s largest SSN. MGNREGA aims at enhancing livelihood security of households in rural India by providing guaranteed wage employment. The scheme has resulted in the creation of sustainable assets that promote the economic and infrastructure development. More than 33 million assets were built in the process of MGNREGA. These assets were spread out in 262,380 smallest units of administration covering 6887 sub-districts with the participation of more than 250 million human manpower. The Sustainable Development Goals (SDG) aims to end poverty, protect the planet and ensure that all people enjoy peace and prosperity. The 17 goals tackle the root cause of poverty and attempts to make a positive change for both people and planet. Ecological regeneration or rejuvenation during the development of the assets generated numerous tangible and intangible benefits to the community in a sustainable way. MGNREGA, a federal government-sponsored scheme, using a decentralized approach is directly or indirectly helping to achieve all the 17 goals of sustainable development in India. This article takes a holistic approach to correlate and map the concepts and outcomes of MGNREGA programme with SDG. This article emphasises the fact that community-based participation in the planning and development activities at the regional levels will yield benefits to the biosphere, society and economy at the national level.     

基于有机污染物生物有效性的土壤环境质量基准的探讨

我国的土壤污染日益严重,由于污染物对土壤生物产生的毒性效应与其生物有效态含量相关,以污染物总量为指标的土壤环境质量标准已无法满足当前土壤管理的需求,亟需开展以生物有效性为基础的土壤环境质量基准的研究工作。目前对土壤中重金属的生物有效性的研究较为深入,但是针对有机污染物的土壤生物有效性研究相对匮乏。本研究综述了有机污染物在土壤中的结构形态、吸附吸收和迁移转化,以及影响土壤中有机污染物生物有效性的关键因素。从我国有机污染物的污染现状、土壤类型分布情况,以及物种选择3个方面对基于生物有效性的土壤环境质量标准/基准的制定进行探讨,以期为我国根据国情制定适合本土特征的生态安全土壤质量标准提供借鉴。     

Determination of estrogens and estrogenic activities in water from three rivers in Tianjin, China

Studies on estrogenic disrupting compounds(EDCs) occurrence and identification of main responsible compounds in river water discharged into the sea are of significance.In the present research,we screened estrogenic activities of 10 river water samples from 3 main rivers discharged into Bohai Sea in Tianjin using a recombinant two-hybrid yeast assay and chemical analysis by gas chromatography-mass spectrometry.All sample extracts induced significant estrogenic activity,with 17β-estradiol equivalents(EEQ) of raw water ranging from 5.72 to 59.06 ng/L.Six most concerned EDCs in the river water samples including estrone,17β-estradiol,17α-ethinylestradiol,estriol,diethylstilbestrol and estradiol valerate were determined,with their concentrations up to 50.70,31.40,24.40,37.20,2.56,and 8.47 ng/L,respectively.Through causality analysis by comparing the EEQ values of yeast assay and chemical analysis,17α-ethinylestradiol and 17β-estradiol were identified as the main contributors to the estrogenic effects of the river samples,accounting for the whole estrogenic activities(62.99% to 185.66%),and estrogen antagonistic compounds might presented in the heavy polluted water samples.The proposed approach using both chemical analysis and bioassay could be used for identification and evaluation of the estrogenic activity of EDCs in river water.