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Implicit theories lead individuals to make assumptions about one trait based on their knowledge of another trait. This study experimentally examined Implicit Stress Theory under conditions of high and low performance information. The objective was to test for evidence of Implicit Stress Theory in ratings of effectiveness, commitment, and burnout. Results indicated moderate support for Implicit Stress Theory such that raters evaluated employee burnout and commitment as higher when the employee was perceived to be working under stressful conditions. Interestingly, the data suggested stronger support (based on the proportion of variance explained) for an Implicit Performance Theory such that information regarding good performance was associated with higher levels of commitment and less burnout than poor performance. 相似文献
74.
Mark D. Kilby James Castleman Stephanie Allen Samantha Doyle Denise K. Williams 《黑龙江环境通报》2023,43(11):1472-1476
We report a case of a female fetus born to an unrelated couple with a complex fetal phenotype of a pleural effusion, a cardiac malformation, and syndactyly of the toes. Prenatal exome sequencing identified a variant of uncertain significance in the PORCN gene that was upgraded to likely pathogenic following postnatal clinical examination. The phenotype described in cases with variants in the PORCN gene is often associated with findings that cannot be prospectively diagnosed by ultrasonography. This is the first report of a prenatal phenotype involving a fetal effusion associated with variants in the PORCN gene, with skeletal findings identified later in gestation on ultrasonography. The diagnosis was confirmed on neonatal examination. 相似文献
75.
The objective of assisting with tasks and decisions during incident response is to reduce the risks to victims and rescue personnel while increasing the efficiency of the rescue operation. Handling uncertain information during urban search and rescue (USAR) missions represents additional stress to the decision‐maker. The aim of this study is to identify the decision‐making behaviour of rescuers during USAR missions to pinpoint trapped or buried victims in debris in order to design assistance technologies and decision‐support systems that meet their needs. In 2010, a survey was conducted among 10–15 per cent of all German rescue personnel specialised in search tasks. One of the major results of this survey is that a subjective assessment of the reliability of information available from heterogeneous sources influences the rescuers’ actions and that there is no methodology for decision‐making involving uncertain information. In addition, the study found that compliance with procedures does not require assistance. 相似文献
76.
Biodegradable Polyester-Based Blend Reinforced with Curauá Fiber: Thermal,Mechanical and Biodegradation Behaviour 总被引:1,自引:1,他引:0
Fernanda Harnnecker Derval dos Santos Rosa Denise Maria Lenz 《Journal of Polymers and the Environment》2012,20(1):237-244
Biodegradable composites can be produced by the combination of biodegradable polymers (BP) as matrix and vegetal fibers as
reinforcement. Composites of a commercial biodegradable polymer blend and curauá fibers (loaded at 5, 15 and 20 wt%) were
prepared by melt mixing in a twin-screw extruder. Chemical treatments such as alkali treatment of the fiber and addition of
maleic anhydride grafted polypropylene (MA-g-PP) as coupling agent were performed to promote polymer/fiber interfacial adhesion so that mechanical performance can be
improved. The resulting composites were evaluated through hardness, melt flow index and tensile, flexural and impact strengths
as well as water absorption. Thermal analysis and Fourier transform infrared spectroscopy were also employed to characterize
the composites. The polymer/fiber interface was investigated through scanning electron microscopy analysis. The biodegradability
of composites was evaluated by compost-soil burial test. The addition of curauá fiber promoted an increase in the mechanical
strengths and composites treated with 2 wt% MA-g-PP with 20 wt% curauá fiber showed an increase of nearly 75% in tensile and 56% in flexural strengths besides an improvement
in impact strength with respect to neat polymer blend. Nevertheless, treated composites showed an increase in water absorption
and biodegradation tests showed that the addition of fiber retards degradation time. The retained mass of BP/20 wt% fiber
composite with MA-g-PP and neat BP was 68 and 26%, respectively, after 210 days of degradation test. 相似文献
77.
Salt marshes dominated by Spartina alterniflora and the associated networks of tidal creeks that drain them are characteristic geographical features of southeastern estuaries, important nursery habitat areas, and preferred sites for residential development. As the size of the coastal population increases, so has the number of requests for dock permits. With each new request for a dock permit, public concerns about the cumulative environmental impacts of dock proliferation on the coastal environment have increased. The objective of this particular study was to evaluate the impacts of shading by dock structures on stem densities of S. alterniflora in South Carolina coastal marshes. Shading impacts under individual docks were extrapolated to the tidal creek (local), county, and statewide scales. Dock structures were sampled both under and next to the walkway in the Charleston Harbor area of South Carolina. The density of S. alterniflora under docks was significantly lower than that which occurred next to the docks (i.e., 5 m away) for the short-form, tall-form, and both forms combined. We estimated that shading effects from dock structures in South Carolina decreased the stem density of S. alterniflora by 71%. Dock shading effects were small when evaluated from the perspective of the amount of marsh that occurs within specific tidal creeks (0.03–0.72%), in coastal counties at a maximum dock length (0.01–0.98%), or statewide (0.01–0.13%) at a maximum dock length. However, approximately 7,000 docks have been permitted over the last decade, resulting in a loss of salt marsh equivalent to 60 ha.1Denise M. Sangers present address: Office of Ocean and Coastal Resource Management, South Carolina Department of Health and Environmental Control, 1362 McMillan Avenue, Suite 400 Charleston, South Carolina 29405, USA.
2 A. Frederick Hollands present address: Hollings Marine Laboratory, National Oceanic and Atmospheric Administration, 331 Fort Johnson Road, Charleston, South Carolina 29412, USA. 相似文献
78.
Using the methodology of policy capturing, this research identifies the role that performance, time on the job, commitment of long-term employment and employability play in judgment of termination fairness and employer obligations. Previous research (Rousseau and Anton, 1988) found that seniority and past commitments of long-term employment contributed significantly to judgments of termination fairness and obligation. The present study considered these variables along with performance (past, present and future potential) using 116 participants in human resource management courses. Results indicated that present performance, time on the job, and commitments affect judgments regarding termination fairness and obligation. Past and future performance, however, had no impact on these judgments. Implications of the findings for understanding employer and employee obligations are discussed. 相似文献
79.
Founded on the assumption that communicator style is situationally and contextually influenced, this study investigates the effects of job-related stress on communicator style. It was specifically designed to measure the effects of job-related stress factors on employee communicator style within the context of a medical center organization. Three central research questions are posed: (1) what, if any, meaningful differences in communicator style can be found from general work conditions to stress-specific conditions; (2) do different stress conditions give rise to meaningful differences in communicator style; (3) what communicator style differences exist among three major medical center employee hierarchies in response to stress-specific situations. The results indicate that communicator style in the stress-specific sample was significantly more dominant, open, attentive but less dramatic and friendly. Multivariate analysis revealed that communicator style accounted for the greatest differences between employees who were experiencing stress due to being unprepared to perform their work role. All role-related stress variables were more powerfully discriminated by the communicator style variables than department/unit stress (stress at the work group level). Finally, communicator style variables provided statistically significant discrimination of three occupational groups: physicians, administrators/managers, and line employees. Physicians appeared to be more assertive and less supportive in their communication; administrators/managers were assertive but also supportive while line employees were both submissive and supportive in their communicator style. These three employee groups were also discriminated using the job-related stress variables. Although statistically significant findings were obtained, the discriminant functions were less powerful than the communicator style discriminant functions. 相似文献
80.
Marcello M. Veiga Denise Nunes Bern Klein Janis A. Shandro P. Colon Velasquez Rodolfo N. Sousa 《Journal of Cleaner Production》2009,17(15):1373-1381
Artisanal small-scale gold miners (ASM) occasionally employ whole ore amalgamation by adding mercury into ball mills to recover gold. In this process, 25–30% of the mercury added is lost to the environment. It is also inefficient less than 30% of gold is recovered. Amalgamation, followed by cyanidation, has been observed at many artisanal mining sites. This combination poses additional environmental and health consequences. Tests with ore samples from Talawaan, North Sulawesi, Indonesia indicate the possibility of replacing mercury by cyanidation in the ball mill, reaching gold extraction of 93% in 6 h of leaching. The gold in the Indonesian ore sample is fine and less than 8% of gold recovery was obtained with gravity concentration of the ore ground 80% below 0.25 mm, which is a reasonably fine grain size for artisanal gold operations. Replacing mercury addition with cyanidation in ball mills was implemented in one artisanal gold mining operation in Portovelo, Ecuador, achieving 95% of gold extraction in 8 h of mill leaching. This technique demonstrated a drastic improvement in gold recovery. It was found to be a simple, inexpensive technique well accepted by local miners. The results from laboratory and field tests are promising; however a thorough investigation into the socio-economic and environmental aspects of this presented alternative must be conducted prior to introduction. 相似文献