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651.
应用五因子二次正交旋转回归试验设计,建立了微生物谷氨酰胺转胺酶 (TG)发酵生产过程中以酶活力和菌体细胞生长量作为目标函数的数学模型,并以此模型对链霉菌 (Streptomycessp. )WJS-825菌株发酵生产TG的培养条件进行优化,确定了影响TG生产的主要因子及其最适取值为多价胨 2. 1%、可溶性淀粉 1. 5%、初始pH 7. 0及培养温度 30℃.以该优化工艺条件进行了 5L发酵罐小试和 200L发酵规模的中试生产.结果表明,在中试发酵生产中使用以豆饼粉部分替代多价胨的经济性发酵优化培养基,以及发酵过程中在线监控pH、溶氧系数等多项发酵调控参数,并分段控制pH、温度、通气量和搅拌转速以及进行适时的流加补充碳源,该菌株生长繁殖能力强、产酶效果好,TG活性达 3. 2u/mL,而且连续重复的中试发酵生产试验的TG产量均稳定在 3. 2u/mL以上. 图 2表 3参 15 相似文献
652.
Summary Plant defence can be induced by herbivory. This is true for both direct and indirect plant defence. Induced direct defence has been the most studied of the two. However, in most cases induced direct defence does not appear to be a water-tight defence option. In contrast, induced indirect defence through the production of herbivore-induced carnivore attractants can be a decisive factor in the extermination of herbivore populations. In this paper the main characteristics of induced attraction of carnivores by plants are reviewed. This includes the similarities and dissimilarities among tritrophic systems. There are two main patterns of induced carnivore attraction. (1) Through the emission of the same bouquet as that emitted by mechanically damaged plants, but in larger quantities and for a longer period of time after damage. (2) Through emission of large amounts of new volatiles that are synthesizedde novo in response to herbivore feeding andnot in response to mechanical wounding.Herbivore populations may be decimated by carnivores. Therefore it should be realized that herbivoreinduced carnivore attractants are essential in an important step in carnivore foraging,i.e. long-distance herbivore location. Once herbivores have started feeding on a plant and direct defence is not effective, induced indirect defence may be decisive for plant survival. Therefore, it is concluded that indirect defence is an essential aspect of induced plant defence directed at herbivorous arthropods. 相似文献
653.
Summary. Allopatric populations of the leaf beetle Chrysomela lapponica are known to feed upon either willow (Salicaceae) or birch (Betulaceae). This study aimed to elucidate the differentiation
process of these allopatric populations. We investigated whether these allopatric populations specialized on different host
plants are still able to produce fertile offspring when interbreeding. Individuals from a population in Finland (willow specialists)
and one in the Czech Republic (birch specialists) were crossed in laboratory. Hybrid formation succeeded only between females
from the Czech, birch specialized population and males from the Finnish, willow specialized population, while no eggs were
produced by females of the willow specialists having mated males of the birch specialists. Behavioral, morphological, physiological,
and chemical features of the F1 hybrids were studied. The chemical composition of larval defensive secretion and feeding preferences of the resulting F1 hybrids mainly showed similarities with the paternal phenotype, while the area of black coloring on the offspring’s elytra
was intermediate between those of the parental elytra. F1 hybrids did not accept the host plant (birch) of their mothers for feeding and only survived on willow. Thus, since mothers
only lay eggs on birch, we found evidence for a postzygotic isolation mechanism between the individuals of the two investigated
populations: when having been mated with willow specialized Finnish males, the birch specialized Czech mothers place the hybrid
eggs on a plant species (birch), on which the hatching larvae cannot survive. 相似文献
654.
洛阳化纤PTA装置污水排放的综合治理 总被引:1,自引:0,他引:1
臧进毅 《石油化工环境保护》2002,25(4):18-21
根据洛阳化纤工程PTA装置污水排放情况及与之配套的化纤污水处理场的处理情况,采取一系列有效措施,治理源头,达到PTA高浓度有机污水达标排放的目的。 相似文献
655.
Krishan P. Singh Carl G. Lonnquist 《Journal of the American Water Resources Association》1972,8(2):239-249
Economics of treatment plant staging or capacity expansions is governed by the initial water demand rate, Q0; the anticipated demand growth rate, G; the discount rate, D; the cost of operation, maintenance, and repair (OMR); the useful plant life, T, as a function of the quality of design, construction, and OMR; the treatment plant load factor, Lf; the salvage value of the plant at the end of the project period; the efficiency of the plant-staging design, eta; and the length of the project period, Ts. Various staging policies are investigated to find an optimal policy. The desirability of adopting a staging policy is governed by the magnitude of percent savings that can be achieved by adopting this policy instead of a no-staging policy. A detailed analysis of the problem shows that the percent savings because of staging increase with an increase in Q, G, D, T, and eta;. A reduction in the plant load factor increases the total costs. Information about the effect of variation in the parameters should help the planner and designer to work out an economical schedule of treatment plant capacity expansions. 相似文献
656.
以受污染的城市河涌底泥为底质,湿地植物选用风车草(Clinopodium Urticifolium)或短叶茳芏(Cyperus Malaccensis),构建了湿地植物-沉积物微生物燃料电池(P-SMFC)及无植物的沉积物微生物燃料电池(SMFC)共3个电极处理组,研究了P-SMFC与SMFC的产电特性,并探讨了它们与对照组中底泥及上覆水中氮磷的迁移转化规律。结果表明,产电方面,在系统启动运行的7个月内,PSM1、SM和PSM2三个电极处理组均能维持较稳定的产电,输出电压在整个运行阶段总体稳定在0.30~0.50 V,且植物的引入提升了系统的产电性能。底泥修复方面,设置的5个处理组对底泥中有机质均有一定的降解作用,表现出PSM1、SM和PSM2处理组有机质的降解要显著高于PS1和PS2处理组,P-SMFC系统对底泥有机物的去除有显著的促进作用;系统中系统运行前2个月,2个P-SMFC处理组氨氮含量显著低于其他3个处理组,之后随着运行时间的延长,各处理组之间的变化差异性不大,5个处理组底泥中氨氮去除率均达到80%以上;电极的引入对底泥中硝氮的去除没有产生显著影响;各处理组底泥中总磷去除率不同,分别为PSM1处理组8.67%、SM处理组8.89%、PSM2处理组7.33%、PS1处理组12.45%、PS2处理组8.89%,产电过程抑制了磷的迁移,有助于底泥中磷的稳定。 相似文献
657.
658.
新疆火电行业SO2排放现状及控制对策 总被引:2,自引:0,他引:2
新疆火电行业是新疆SO2排放大户,其排放量占全疆工业SO2排放量的43.4%,且有逐年递增的趋势,而其去除率却一直处于较低水平.乌鲁木齐华电红雁池电厂等5家火电厂SO2的排放量排在新疆火电行业之首,应而需将这5家火电厂SO2排放作为重点监控对象,并提出了火电厂减排SO2的几点对策和建议. 相似文献
659.
Mechanistic Virtual Modeling: Coupling a Plant Simulation Model with a Three-dimensional Plant Architecture Component 总被引:3,自引:0,他引:3
Eric Jallas Ron Sequeira Pierre Martin Sam Turner Petraq Papajorgji 《Environmental Modeling and Assessment》2009,14(1):29-45
The aim of this research is to integrate plant architectural modeling or “visualization modeling” and “mechanistic” or physiologically
based modeling to describe how a real plant functions using a virtual crop. Virtual crops are life-like computer representations
of crops based on individual plants and including the representation of the substrate on which the plants grow. The integration
of a three-dimensional expression and the mechanistic model of plant development and growth requires the knowledge of the
position of the organs along the different plant axes (the topology), their sizes, their forms, and their spatial orientation.
The plant simulation model simulates the topology and organ weight or length. The superposition of spatial position and the
topology produces the architecture of the plant. The association between sizes and organs creates what we refer to as the
plant morphological model. Both components, the architectural model and the morphology model, are detailed in this paper.
Once the integration is complete, the system produces a movie-like animation that shows the plant growing. The integrated
model may simulate one or several plants growing simultaneously (in parallel). Visual capabilities make the proposed system
very unique as it allows users to judge the results of the simulation the same way a farmer judges the situation of the crops
in real life, by visually observing the field. 相似文献
660.
Kuroshima KN Barreiros MA Lacava LA Costódio PF 《Environmental monitoring and assessment》2007,129(1-3):179-187
Since February 1999, the Municipal Wastewater Treatment Plant (MWTP) of Balneário Camboriú, Brazil, started a complementary
treatment with ClO2 application on its effluent. It was realized to minimize its impacts caused by increase of the population during summer.
This study was realized in order to verify the influence of this compound in the water quality and the environmental evaluations.
Samples of surface water were collected in this environment between January 1997 and June 2001 for chemical and microbiological
surveys. The results had shown that after application of ClO2, fecal coliforms were decreased about six times in the beach (2.3 × 103 to 3.5 × 102 MPN/100 ml) and three times in the river (3.3 × 104 to 1.0 × 104 MPN/100 ml), during summer time. NH4
+ showed an increase of about four times and 1.5 times, respectively, to beach and river. These results are showing the influence
of ClO2 on chemical and microbiological parameters. 相似文献