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茜红染料废水光助氧化法降解脱色研究 总被引:1,自引:0,他引:1
主要对光助氧化法处理印染废水进行了实验研究.探讨了单纯的紫外光光照时间、H2O2浓度、染料水溶液的初始pH值以及Fenton试剂中H2O2的浓度和Fe2 比值对COD cr去除率和脱色率的影响.结果表明,光助氧化法对茜红染料废水有比较好的处理效果,光照80 min,pH=3,H2O2浓度6 mmol/L,脱色率和COD cr去除率分别达到92.8%和84.4%,加入Fe2 并保持Fe2 :H2O2=1:5,尽管由于Fe2 及Fe3 的存在,脱色率下降为85.4%,而COD cr去除率升高到93.7%. 相似文献
135.
以Bi(NO3)3·5H2O和(NH4)6Mo7O24·4H2O为原料,采用超声辅助沉淀法制备了纳米可见光催化剂γ-Bi2Mo O6,用XRD,SEM,UV-Vis技术对其进行了表征,并以罗丹明B为目标降解物,考察了γ-Bi2Mo O6的可见光催化性能。表征结果显示,产物为高纯度正交结构的纳米γ-Bi2Mo O6,分散性良好。光催化实验结果表明:超声辅助沉淀法制备的γ-Bi2Mo O6的可见光催化活性优于普通沉淀法制备的产品;以超声辅助沉淀法制备的γ-Bi2Mo O6为光催化剂,在初始罗丹明B质量浓度为10 mg/L、初始溶液p H为7.2、γ-Bi2Mo O6加入量为10 g/L的最优条件下,反应180 min时的罗丹明B降解率达到97.48%。 相似文献
136.
Hong Liu Hai Ren Qiang Liu XiangYing Wen Michael Maunder JiangYun Gao 《Conservation biology》2015,29(6):1537-1551
We assessed the current status of plant conservation translocation efforts in China, a topic poorly reported in recent scientific literature. We identified 222 conservation translocation cases involving 154 species, of these 87 were Chinese endemic species and 101 (78%) were listed as threatened on the Chinese Species Red List. We categorized the life form of each species and, when possible, determined for each case the translocation type, propagule source, propagule type, and survival and reproductive parameters. A surprisingly large proportion (26%) of the conservation translocations in China were conservation introductions, largely implemented in response to large‐scale habitat destruction caused by the Three‐Gorge Dam and another hydropower project. Documentation and management of the translocations varied greatly. Less than half the cases had plant survival records. Statistical analyses showed that survival percentages were significantly correlated with plant life form and the type of planting materials. Thirty percent of the cases had records on whether or not individuals flowered or fruited. Results of information theoretic model selection indicated that plant life form, translocation type, propagule type, propagule source, and time since planting significantly influenced the likelihood of flowering and fruiting on the project level. We suggest that the scientific‐based application of species conservation translocations should be promoted as part of a commitment to species recovery management. In addition, we recommend that the common practice of within and out of range introductions in nature reserves to be regulated more carefully due to its potential ecological risks. We recommend the establishment of a national office and database to coordinate conservation translocations in China. Our review effort is timely considering the need for a comprehensive national guideline for the newly announced nation‐wide conservation program on species with extremely small populations, which is expected to stimulate conservation translocations for many species in the near future. 相似文献
137.
资金投入不足、建设者与受益者之间利益分配关系割裂,是影响生态环境建设与保护工作的重要因素,本文以生态环境服务功能的经济学特征分析为基础,指出生态环境建设的实质是环境再生产,认为尽快建立起符合中国国情和市场经济体制要求的森林生态效益补偿制度是确保环境再生产过程顺利进行的重要任务。 相似文献
138.
Christy L. Hoffman Angelina V. Ruiz-Lambides Edgar Davila Elizabeth Maldonado Melissa S. Gerald Dario Maestripieri 《Behavioral ecology and sociobiology》2008,62(11):1711-1718
In sexually promiscuous mammals, female reproductive effort is mainly expressed through gestation, lactation, and maternal
care, whereas male reproductive effort is mainly manifested as mating effort. In this study, we investigated whether reproduction
has significant survival costs for a seasonally breeding, sexually promiscuous species, the rhesus macaque, and whether these
costs occur at different times of the year for females and males, namely in the birth and the mating season, respectively.
The study was conducted with the rhesus macaque population on Cayo Santiago, Puerto Rico. Data on 7,402 births and 922 deaths
over a 45-year period were analyzed. Births were concentrated between November and April, while conceptions occurred between
May and October. As predicted, female mortality probability peaked in the birth season whereas male mortality probability
peaked in the mating season. Furthermore, as the onset of the birth season gradually shifted over the years in relation to
climatic changes, there was a concomitant shift in the seasonal peaks of male and female mortality. Taken together, our findings
provide the first evidence of sex differences in the survival costs of reproduction in nonhuman primates and suggest that
reproduction has significant fitness costs even in environments with abundant food and absence of predation. 相似文献
139.
宋昕旖聂瑾璐杨梦涵喻懋椿陶梁明冯虎元潘建斌 《应用与环境生物学报》2022,(6):1527-1533
Polygonum viviparum, which reproduces sexually and asexually, is widely distributed in the Qinghai-Tibet Plateau, and its reproduction strategies are very sensitive to changes in the environment. This study aimed to elucidate the effect of altitude on the photosynthetic characteristics and reproductive strategies of P. viviparum. This study was conducted to investigate the responses of photosynthetic, vegetative, and reproductive traits of P. viviparum populations along six altitudinal gradients in the eastern part of the Qilian Mountains in China. Our results indicated that, with increasing altitude, the net photosynthetic rate of P. viviparum showed an increasing trend, reaching its maximum value (14.39 μmol m–2 s–1) at 3 700 m above sea level. The transpiration rate showed an increasing trend, followed by a decreasing trend, and the intercellular CO2 concentration did not differ significantly between altitudes. With increasing altitude, the plant height and leaf area of P. viviparum showed a downward trend, the aboveground and underground biomass decreased, and the specific leaf area initially decreased and then increased. However, the leaf greenness index showed an upward trend, and the number of stomata in the upper and lower epidermis of leaves initially increased and then decreased. With increasing altitude, the proportion of inflorescence length per plant (the ratio of inflorescence length to plant height), the proportion of bulbil length per inflorescence (the ratio of bulbil length to inflorescence height), and the proportion of the number of bulbils per inflorescence (the ratio of the number of bulbils to the total number of flowers and bulbils) showed an increasing trend. Air temperature and light intensity are the major environmental factors affecting the photosynthetic characteristics and functional traits of P. viviparum. Thus, P. viviparum is exposed to more environmental stresses and obtains less energy when altitude increases, but it adapts to the harsh alpine environment by increasing the photosynthetic capability per unit area. With increasing altitude, P. viviparum populations may be sustained by investing less energy in vegetation and more in reproduction, especially asexual reproduction. © 2022 Science Press. All rights reserved. 相似文献
140.
Changes in male blood plasma testosterone and cortisol in response to exposure to scent marks (urine and midventral gland secretion, MVGS) of conspecific males and diestrous females in different seasons have been studied in the desert hamster (Phodopus roborovskii), a species whose ecological features are poorly known. The results show that a significant increase in the plasma testosterone level is observed in winter (only to female MVGS), spring (to female MVGS and urine), and summer (to female urine), but not in autumn. The level of plasma cortisol significantly increases only in response to female urine in spring and male MVGS in summer. 相似文献