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51.
观赏果树在乌鲁木齐市绿化环境的效果及应用分析   总被引:1,自引:0,他引:1  
为比较不同观赏果树在乌鲁木齐市对绿化环境的效果,分析不同观赏果树在乌鲁木齐市的应用方式.本实验以乌鲁木齐市20年生的常见观赏果树山桃、新疆梨等为实验材料,分析其可观赏性、生长期、生长状况、抗性、产量、滞尘量、绿化环境的不利因素,结果显示8种观赏果树绿化环境的效果从优往劣依次是黑桑、红果山楂、黄太平、毛杏、山桃、李子、新疆梨、葡萄.对乌鲁木齐市绿化环境的建设,这8种观赏果树与其他观赏植物配合进行花园立体绿化环境,效果更好.  相似文献   
52.
利用铁碳微电解-微波强化Fenton联合工艺处理垃圾渗滤液膜滤浓缩液,探讨了微波功率、微波作用时间、H2O2投加量对微电解出水处理效果的影响。同时将铁碳微电解出水COD浓度、微波功率、微波作用时间、H2O2投加量对处理效果的影响建立了正交试验,结果表明:各因素对COD去除率影响的主次关系为:微电解出水COD微波功率H2O2投加量微波作用时间。  相似文献   
53.
Sewage sludge addition to agricultural lands requires judicious management to avoid environmental risks arising from heavy metal and nitrate contamination of surface water and accumulation in edible plants. A field study was conducted on a silty-loam soil of 10% slope at Kentucky State University Research Farm. Eighteen plots of 22 × 3.7 m each were separated using metal borders and the soil in six plots was mixed with sewage sludge and yard waste compost mix (SS-YW) at 15 t acre?1, six plots were mixed with sewage sludge (SS) at 15 t acre?1, and six unamended plots that never received sludge were used for comparison purposes. Plots were planted with eggplant, Solanum melongena L. as the test plant. The objectives of this investigation were to: 1) assess the effect of soil amendments on the transport of NO3, NH4, and heavy metals (Cd, Cr, Ni, Pb, Zn, Cu, and Mo) into surface water; 2) investigate the effect of soil amendments on heavy metal bioavailability in eggplant fruits at harvest; and 3) assess chemical and physical properties of soil following addition of soil amendments and their impact on the yield and quality of eggplant fruit. SS-YW treatments reduced runoff water by 63% while plots incorporated with sewage sludge alone reduced runoff water by 37% compared to control treatment. The SS-YW treatments transported more mineral nitrogen (NO3-N and NH4-N) in runoff water than SS treatments. Total marketable yield (lbs acre?1) and number of eggplant fruits were greatest in SS-YW treatments. This response may be due to improved soil porosity, water, and nutrient retention of the soil amended with SS-YW mixture. Concentrations of heavy metals in soil amended with sludge were below the U.S. Environmental Protection Agency (USEPA) limits. Chromium, Ni, Zn, and Cu were taken up by eggplant fruits but their concentrations were below the Codex Commission allowable levels.  相似文献   
54.
This research conducted on municipal solid waste management for the first time quantified food spoilage as being 8.8% weight of all officially collected household garbage in the Brazilian city under study. The unexpected size of this waste fraction gave rise to work on the causes of waste and on its distribution over the product life cycle specific to fruit and vegetables. Waste was defined as being the combination of losses and scraps. Administrative shortcomings were identified as basic reasons for waste. At the producer and consumer ends of the cycle, negligence was shown to be the single most important problem. Fruit and vegetables deteriorate during the operations of handling, transport, packaging, storage, selling and consumption. The study detailed the occurrence of waste at all of these stages. In the medium-size Brazilian city, the total waste of fruit and vegetables was shown to amount to 16.6% weight in the marketing stage of the life cycle. At the consumer level, it was measured as 3.4% weight of all household garbage. Specific reasons for this waste were identified at the levels of producer, wholesaler and retailer. Short-term remedies were pointed out that invariably corrected deficient management procedures. It was shown that very simple administrative measures can significantly reduce the spoilage of fruit and vegetables. Long-term strategies involve the creation of sample cases for administration of the fruit and vegetables life cycle at all stages.  相似文献   
55.
赣中南柑橘果实生长发育规律与栽培技术关系   总被引:1,自引:0,他引:1  
通过果实体积的累积生长量,日均生长速度和相对生长速率三个指标的测定。可得到各类果实生长的“S”形曲线。生长呈三个时期,第一期为细胞分裂期,这个时期,生长速度较慢,而相对生长速率最高,是是实生长能力最高阶段;第二期为细胞膨大期,生长速度最快时期,而相对生长速率则呈下降趋势;第三期为成熟期,日均生长速度和相对生长速率都是低速和稳定时期。主要内部生理变化,柑橘各类果 个指标各异,此外,果实生长过程中,有  相似文献   
56.
西藏尼洋河流域果树资源及其开发途径探讨   总被引:3,自引:0,他引:3  
西藏尼洋河流域果树资源丰富,栽培果树有苹果、梨、桃、李、杏和葡萄等9种和90多个品种;野生果树有7科16属41种,目前利用程度低,开发潜力大。文中提出了该地区果树资源的开发途径,在尼洋河下游和雅鲁藏布江的扎绕乡至派乡之间段的河谷地上形成“Y”字型的水(干)果种植带,建设成为西藏的水(干)果生产基地,并对现有果园改造更新,充分利用野生水果资源,建立果品综合加工厂等以满足西藏市场对水果和果品的需要。  相似文献   
57.
污泥上清液的有机物浓度及其生物降解性   总被引:2,自引:0,他引:2  
在进行城市生活污水的生物处理过程中,会产生一定量的生化污泥。在浓缩和处理剩余污泥时,所产生的含高浓度有机物的污泥上清液被回流到污水处理系统,不适当的回流会增加水处理系统的负荷并严重影响,出水的水质。实验证明,在污泥浓缩中,污泥上清液中有机物含有与浓缩温度成e指数关系,与浓缩时间成小于1的指数关系。  相似文献   
58.
秦岭北麓平原对全球变暖的响应及其对果业发展的影响研究   总被引:13,自引:0,他引:13  
论文分析了秦岭北麓8县的近41年的气候变化规律,发现该地区气候变化趋势与全国和全球相似,向暖干化方向发展。采用近41年气候特征值对苹果适宜性进行评价,发现该地区并不是苹果生长的适宜区。夏季高温、较高的相对湿度和较短的日照时数是苹果生长的不利因素。结合目前的气候变化趋势,推论出该地区苹果的病虫害将会加重,苹果质量将进一步下降。地区果业发展中,减少苹果栽种面积和优化果品生产结构仍然具有一定潜力。  相似文献   
59.
Abstract:  Self-incompatibility systems prevent self-fertilization in angiosperms. Although numerous S alleles are usually maintained by negative frequency-dependent selection, the number of S alleles can be low in small populations, which limits mate availability and reduces fecundity in endangered populations of self-incompatible plants. Despite the increasing evidence of the negative effect of self-incompatibility in small populations, the direct link between the number and the distribution of S alleles and their reproductive consequences has been rarely reported. Brassica insularis is a rare self-incompatible species with medium to very small populations. Results of a previous study showed that the smallest population has very few S alleles. We investigated whether reduced mate availability affects reproduction in this species. We compared the pollination success and the fruit set in 4 populations differing in population size and number of S alleles. Our results suggest that reproduction may be negatively affected by the low S-allele diversity in the smallest population. Nevertheless, other populations also had reduced fruit set that could not be attributed to self-incompatibility alone.  相似文献   
60.
为查明安徽某典型硫铁矿集中开采区周边土壤重金属元素污染特征及污染来源,采集了研究区42个表层土壤样品和2个垂向剖面的16个土壤样品测定其pH值及Zn、Cu、Cd、Pb、Cr、Ni、Hg和As重金属元素含量,运用ArcGIS反距离权重插值法、内梅罗综合指数法、主成分分析法和绝对因子得分-多元线性回归(APCS-MLR)受体模型等方法进行了重金属元素分布特征分析、污染评价和来源解析.结果表明,土壤中8种重金属元素的含量平均值是铜陵地区背景值的1.03~13.14倍,Zn、Cu、Cd、Pb、Hg和As这6种重金属元素局部富集明显,在空间分布上与采矿活动位置基本一致.单因子污染指数评价显示,Zn、Cu、Cd、Pb和As这5种元素存在不同程度的污染风险,Cd和Cu元素污染程度最为严重,中度污染以上占比分别为47.62%和42.86%;内梅罗综合污染指数评价显示,研究区土壤样点中度污染以上占比为61.90%;地累积指数评价显示,研究区Zn、Cu、Cd、Pb、Hg和As这6种重金属元素污染程度主要为轻污染~强污染.在土壤剖面垂向变化上,重金属元素易在土壤表层富集,向深部迁移较缓慢,高含量主要在1 m以上位置.源解析表明,Zn、Pb和As的来源中地质高背景和采矿活动贡献率分别为37.82%、43.49%和46.63%,成土母质风化的自然来源贡献率分别为34.02%、40.88%和38.52%;Cr和Ni来源主要为成土母质风化的自然来源,贡献率分别为91.95%和73.68%;Cu的来源中地质高背景和采矿活动贡献率为41.91%,大气沉降和农业综合源贡献率为41.30%;Hg的来源较多,成土母质风化的自然来源贡献率为35.60%,地质高背景和采矿活动贡献率为29.87%,未知来源贡献率为34.05%;Cd的主要来源为大气沉降和农业综合源,贡献率为81.81%.  相似文献   
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