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551.
The German cockroach is the most common pest of urban, low-income housing in the United States and is associated with high pesticide use by residents. Cockroach allergen is implicated in asthma exacerbation and initiation and in the growing social and medical aspects of the disease. A safe and secure home environment is an environmental justice issue, and environmentally sound and effective models of cockroach control are needed in public and low-income multifamily housing. One model that offers potential is the integrated pest management (IPM) peer educator model (IPM Educator) in public housing as a component of IPM. A pre-post-analysis of an IPM Educator pilot programme in Boston public housing was undertaken. Thirty-four moderate- to high-infested units received baseline assessment and three applications of gel baits and IPM treatment by a pest control operator. Before the first pest control application, residents received written notice to prepare their units for treatment, a standard procedure. Before the second and third pest control treatments, an IPM Educator instructed residents in basic pest biology and habits, preparation for treatment, and the role of sanitation in pest control. Results showed a significant improvement in rate of preparation for pest control treatment after the IPM Educator intervention when compared with the preparation rate before the education intervention, and a significant reduction in cockroach populations by the third visit in units that were prepared and had improved sanitation, when compared with unprepared units and unclean units. The IPM peer educator is a promising, low-cost model of educating and engaging residents of urban, low-income, multifamily housing in environmentally sound pest control, thereby giving them some power and control over their living environment. It is also a potential source of professional training and jobs for public housing and other low-income housing residents.  相似文献   
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In recent years, as part of its neoliberal development paradigm, the Government of the Philippines has engaged in efforts to encourage extraction of the nation's mineral resources. The Philippines is also a country where decentralization has devolved substantial powers to local governments. Concern over potentially adverse environmental effects has led to opposition to mining by some local governments in the Philippines. This opposition has led to the withholding of consent to mining projects by local governments and, in some cases, the implementation of moratoriums banning mining. Central to this opposition have been the activities of civil society groups, and their collaboration with local governments. This collaboration has involved the drafting of legislation prohibiting mining and support of candidates for office who are opposed to mining. Collectively, Filipino local governments and civil society groups are examples of the concept of governance, a dispersed process wherein society manages itself for the betterment of all its members. For mining companies seeking to implement projects, it is no longer sufficient to have the consent of the national Government — that of local governance forces must also be considered.  相似文献   
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The tenth Soviet five year plan projected increased extraction of mineral resources and improved utilization of those resources. Through 1976 and 1977, actual production closely parallelled planned production in most resources. Even so, 1978 was a critical year for Soviet resources production, and may determine whether the goals of the tenth plan are achieved. Other areas of Soviet resource policy which are discussed include the drive to accelerate Siberian and far eastern development, the effort to improve capital and manpower efficiency, the attempt to improve resource use and reduce non-essential consumption, and the effort to import advanced extractive technology and capital. The article concludes with the observation that with the difficulties facing the Soviet extractive industries, the tenth plan may be the last which projects and strives for a rapid expansion of the Soviet resource base.  相似文献   
557.
Temperature data obtained from NUC Tower, San Diego, California during May–June 1968 provide input to a three-wave period version of MOVER, a computer model that simulates organism diurnal vertical migration through an internal wave field. The locally characteristic wave periods are 21.50 h, 12.50 h and 0.42 h. The phase of the modeled interval wave spectrum matches the field observations for a 10-day period preceding and including a red tide. MOVER's output shows a rapid aggregation of representative phytoplankton under all modeled conditions. The aggregation or red tide occurs at the geographic location of NUC Tower under certain organism behavioral regimes. Whether these conditions actually occurred at NUC Tower in May 1968 is not certain from the available data.  相似文献   
558.
The parental origin of triploidy in 19 cases was examined by inheritance of DNA microsatellites and by methylation patterns of SNRPN or PW71 (where parents' blood was unavailable). The fetal and placental morphology on these cases was reviewed. The phenotype of the fetuses with non-mosaic triploidy was assessed in relation to the two types described by McFadden and Kalousek. Of the diandric fetuses three of the six showed mild-to-moderate symmetrical growth retardation and the other three had growth characteristics in accordance with their gestational ages. This study would suggest the fetal triploid ‘Type 1’ definition be modified to ‘well grown to moderate symmetrical IUGR’ to allow for such variation. In the digynic fetuses (McFadden/Kalousek Type 2) there were poor growth characteristics with IUGR being more severe and asymmetrical. The diandric fetuses were as common as digynic fetuses in this series. The ratio of diandric to digynic specimens was 11:8 but if only fetal specimens (not embryos or mosaic children) were included the ratio was 6:5. Many diandric conceptions end as partial moles but later in gestation diandric fetuses may be well grown. It is proposed that there may be a survival barrier for diandric fetuses early in gestation (possibly based on the proportion of vascularised placental villi), although once this is passed the diandric fetuses are comparatively more viable and better grown than digynic fetuses. In the XXY triploid fetuses, 5/6 had hypoplastic or ambiguous external genitalia (two were recorded as of female phenotype) as has been reported previously. In these, the gonadal histology was testicular in all the diandrics but in the single digynic XXY case, sex reversal was complete with normal uterus and Fallopian tubes and the gonads were histologically ovaries. Two triploid/diploid mosaics were proven to be due to digyny. The probable cause is delayed incorporation of the second polar body into a blastomere and there was evidence of identical alleles from the same sperm being present in both diploid and triploid cells. In one of these triploid/diploid mosaics in which there was a termination of pregnancy (TOP) after prenatal karyotyping the diploid cell line had trisomy 16 which was not evident in the triploid line. This trisomy was probably of post-zygotic origin and we suggest the fetus was rescued by the prominence of the triploid line. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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A phosphorus (P) index for pastures was developed to write nutrient management plans that determine how much P can be applied to a given field. The objectives of this study were to (i) evaluate and compare the P index for pastures, particularly the P source component, and an environmental threshold soil test P level by conducting rainfall simulations on contrasting soils under various management scenarios; and (ii) evaluate the P index for pastures on field-scale watersheds. Poultry litter was applied to 12 small plots on each of six farms based on either an environmental threshold soil test P level or on the P index for pastures, and P runoff was evaluated using rainfall simulators. The P index was also evaluated from two small (0.405 ha) watersheds that had been fertilized annually with poultry litter since 1995. Results from the small plot study showed that soil test P alone was a poor predictor of P concentrations in runoff water following poultry litter applications. The relationship between P in runoff and the amount of soluble P applied was highly significant. Furthermore, P concentrations in runoff from plots with and without litter applications were significantly correlated to P index values. Studies on pastures receiving natural rainfall and annual poultry litter applications indicated that the P index for pastures predicted P loss accurately without calibration (y = 1.16x - 0.23, r(2) = 0.83). These data indicate that the P index for pastures can accurately assess the risk of P loss from fields receiving poultry litter applications in Arkansas and provide a more realistic risk assessment than threshold soil test P levels.  相似文献   
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