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241.
Pacific salmon are particularly susceptible to copper (Cu)-induced olfactory injuries that can ultimately inhibit neurobehaviors critical to survival. However, the molecular mechanisms underlying Cu-mediated olfactory impairment remain poorly understood. In the present study, we conducted a short-term Cu exposure at levels relevant to urban runoff (5, 25 and 50 ppb) , and investigated the roles of impaired olfactory signal transduction and induced apoptosis as underlying mechanisms of olfactory injury. Increased cell death in the olfactory epithelium was evident in coho receiving 4 h exposures to 25 and 50 ppb Cu. Expression of olfactory marker protein (omp), a marker of mature olfactory sensory neurons, also decreased at 50 ppb Cu. Immunohistochemical analysis of coho olfactory epithelium demonstrated a loss of type 3 adenylate cyclase (ACIII) in the apical olfactory epithelium cilia at all levels of Cu exposure, suggesting an inhibitory effect of Cu in olfactory signaling. Accompanying the loss of ACIII in Cu-exposed coho were reduced intracellular cyclic guanosine monophosphate (cGMP) levels in the olfactory rosettes. Collectively, these results support a linkage among the initial steps of olfactory signaling in Cu-induced salmon olfactory injury, and suggesting that monitoring olfactory cGMP levels may aid in the assessment of salmon olfactory injury. 相似文献
242.
Soy protein plastics are a renewable, biodegradable alternative to fossil fuel-based plastic resins. Processing of soy protein
plastics using conventional methods (injection molding, extrusion) has met with some success. Viscosities of processable formulations
that contain soy protein along with the necessary additives, such as glycerol and cornstarch, have not been reported, but
are necessary for extrusion modeling and the design of extrusion dies. Resins consisting of soy protein isolate-cornstarch
ratios of 4:1, 3:2, and 2:3 were plasticized with glycerol and soy oil, compounded in a twin screw extruder and adjusted to
10% moisture. The effects on viscosity of added sodium sulfite, a titanate coupling agent and recycling were evaluated using
a screw-driven capillary rheometer at shear rates of 100–800/s. The viscosities fit a power-law model and were found to be
shear thinning with power-law indices, n, of 0.18–0.46 and consistency indices, m, of 1.1 × 104–1.0 × 105. Power-law indices decreased and consistency indices increased with increasing soy protein-to-cornstarch ratio and in the
absence of sodium sulfite. Addition of the titanate coupling agent resulted in increased power-law index and decreased consistency
index. Viscosities at a shear rate of 400/s decreased with recycling, except for the 4:1 soy protein isolate to cornstarch
formulation, which displayed evidence of wall slip. Power-law indices were unaffected by recycling. Viscosities in the tested
shear rate range were comparable to polystyrene and low-density polyethylene indicating soy protein plastics are potential
drop-in replacements for commodity resins on conventional plastics processing equipment. 相似文献
243.
城市生活垃圾中可生化单基质的厌氧消化 总被引:1,自引:0,他引:1
在厌氧消化系统中,发酵细菌最主要的利用基质是淀粉、纤维素、脂肪和蛋白质等。本试验分别选取米饭、黄豆、芹菜和肥肉为上述四种基质的代表物质,通过对各物质进行的厌氧消化试验,探讨了它们的厌氧消化性能。结果表明。米饭在发酵初期降解速率最快,酸化也最明显。同时将消化初始阶段的pH控制在6.5时能使消化进入产甲烷阶段,没控制的只能停留在水解产酸阶段。将黄豆厌氧消化初期的pH控制在6.5并不能使消化顺利进行。将芹菜厌氧消化的初始pH值控制在6.5时可以加快它的降解速率。肥肉的厌氧消化也只有在对其消化进程控制pH值时才能顺利被降解。同时肥肉在厌氧消化进程中表现出了高产甲烷性能,产甲烷阶段累积产气量达13758mL,占总产气量的93.59%. 相似文献
244.
造纸废液生产单细胞蛋白 总被引:3,自引:0,他引:3
探讨生物法处理造纸黑液,单细胞蛋白是通过培养单细胞生物而获得的菌体蛋白质。利用产朊假丝鄄母C.utilis发酵亚硫酸造纸液可生产SCP作为动物饲料添加剂。 相似文献
245.
246.
东亚飞蝗和中华蚱蜢的蛋白质与脂肪酸分析 总被引:10,自引:0,他引:10
对东亚飞蝗和中华蚱蜢的蛋白质、氨基酸、脂肪与脂肪酸进行了分析研究 ,并与常见食品的有关营养成分进行比较。结果表明 ,东亚飞蝗和中华蚱蜢是一类高蛋白、低脂肪、富含必需氨基酸和脂肪酸 ,具有很高营养价值的昆虫食品资源。 相似文献
247.
Qing Hu Li Li Yanjuan Wang Wenjuan Zhao Hongyan Qi Guoqiang Zhuang 《环境科学学报(英文版)》2010,22(9):1469-1474
The prediction and assessment of environmental pollution by arsenic are important preconditions of advocating environmental protection and human health risk assessment.A yellow fluorescent protein-based whole-cell biosensor for the detection of arsenite and arsenate was constructed and tested.An arsenic-resistant promoter and the regulatory gene arsR were obtained by PCR from the genome of Escherichia coli DH5α,and phiYFP was introduced into E.coli DH5α as a reporter gene to construct an arsenic-resistant whole-cell biosensor(WCB-11) in which phiYFP was expressed well for the first time.Experimental results demonstrated that the biosensor has a good response to arsenic and the expression of phiYFP.When strain WCB-11 was exposed to As 3+ and As 5+,the expression of yellow fluorescence was time-dependent and dose-dependent.This engineered construct is expected to become established as an inexpensive and convenient method for the detection of arsenic in the field. 相似文献
248.
大豆蛋白和屠宰废水处理工艺研究 总被引:5,自引:0,他引:5
介绍了两公司大豆蛋白废水的水质水量和性质特征,分析工程的工艺设计和调试运行状况。对大豆蛋白和屠宰废水的处理,采用混和处理的总体工艺,理论研究和运行实践表明,混和处理利于均衡生物处理营养,优化厌氧处理工艺型式及参数。污泥培养时,尽快从间歇运行变为连续运行,利于基质和污泥的混和接触,促进油脂和脂肪酸的降解,防止油和脂肪酸的积累及其抑制作用,防止油脂包覆污泥,造成污泥漂浮流失。 相似文献
249.
碱水解法提取剩余污泥蛋白质的条件优化 总被引:4,自引:0,他引:4
为充分提取污水污泥中的细胞蛋白,实现污泥的增值利用,以青岛市李村河污水处理厂剩余污泥为材料,采用碱水解法提取剩余污泥中的蛋白质。正交试验结果表明:水解温度和反应体系pH对蛋白质提取率的影响较大;获得的提取污泥蛋白的最优工艺条件是水解温度为70℃,水解时间为5 h,反应体系pH为12.5,固液比(样品质量g/加水体积mL)为1:4。在上述条件下,剩余污泥蛋白质提取率可达54.49%,水解后的剩余残渣经干燥后测定可知,其质量相对于原污泥样品(干重)质量削减率达到22.95%。 相似文献
250.
生长温度对盾叶薯蓣POD活性等生理特性的影响5 总被引:1,自引:0,他引:1
研究了15℃、20℃、25℃、30℃和35℃五个不同温度条件下盾叶薯蓣一些生理参数的变化.结果显示,盾叶薯蓣叶片的POD活性和MDA含量的变化呈V字形,其中在25℃时处于最低点;可溶性蛋白含量的变化呈M字形,可溶糖含量的变化呈W字形.在15℃、20℃、30℃和35℃下,5 d内,随着时间的延长,MDA含量增加,POD活性、可溶性蛋白和可溶性糖的含量下降;在25℃下,盾叶薯蓣的POD活性以及MDA、可溶性蛋白和可溶性糖的含量变化较小,相对稳定,所以25℃是最为适宜的生长温度.图1表1参20 相似文献