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31.
Cellulose acetate (CA) was synthesized from knitted rag, a cellulosic waste of Textile and Garment industries, in the glacial acetic acid, and subsequently acetic anhydride (Ac2O) in presence of concentrated H2SO4 reaction medium. A low to high substitution products were obtained from single step up to seven steps acetylation of cellulose. In this way, it was possible to produce low cost and different grades or substituted acetylation derivatives of cellulose. The synthesized CA was characterized and investigation of its physical characteristics was done. Solubility, acetyl content, acetic acid content, degree of substitution, and molecular weight of CA increased gradually with the increase of the number of reaction steps attaining optimum value at the fourth step. The acetyl and acetic acid content of CA were increased from 39.95 % to 44.25 %, and from 55.73 % to 61.73 % respectively. Similarly, degree of substitution and molecular weight of CA were increased from 2.47 to 2.94, and from 74,249 to 121,437 respectively.  相似文献   
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Introduction

This paper presents an experimental study in which the effect of three factors (distance between cars, mobile call duration, and time of driving (day or night)) on drivers' reaction time in braking response was investigated.

Methods

The experiment was performed in a real driving environment in which 27 male adults between the ages of 22 and 24 years participated. Three levels of the first two factors (i.e., distance between cars and call duration) and two levels of the last factor (i.e., time of driving) were selected to conduct the experimental study. A full factorial design of experiment with 18 treatment combinations and three replicates of each combination were used. Fifty-four trial runs were performed in a random manner and for each run drivers' reaction time in braking response was measured, which served the data for further analysis. Analysis of variance (ANOVA), interaction effect analysis, and various model adequacy tests were carried out using Design Expert software.

Results

The results of the study indicated that the most important factor affecting the drivers' reaction time in car braking response was the mobile call duration followed by the time of driving, with a high level of interaction between the two factors. It was also found that the distance between cars did not seem to have a significant effect on the reaction time in braking response. It is to be noted that these response times are expected to be higher under normal driving conditions where awareness of experimental environment is not present.

Impact on Industry

The findings of this study would help mobile phone industries in improving safety of mobile phone users in driving environment.  相似文献   
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OBJECTIVE: In developing countries, motorcycle use has grown in popularity in the past decades. Commensurate with this growth is the increase in death and casualties among motorcyclists in these countries. One of the strategic programs to minimize this problem is to reduce motorcyclists exposure by shifting them into safer modes of transport. This study aims to explore the differences in the characteristics of bus and motorcycle users. It identifies the factors contributing to their choice of transport mode and estimates the probability that motorcyclists might change their travel mode to a safer alternative; namely, bus travel. METHODS: In this article, a survey of 535 motorcycle and bus users was conducted in seven districts of Selangor state, Malaysia. A binary logit model was developed for the two alternative modes, bus and motorcycle. RESULTS: It was found that travel time, travel cost, gender, age, and income level are significant in influencing motorcyclists' mode choice behavior. The probability of motorcycle riders shifting to public transport was also examined based on a scenario of a reduction in bus travel time and travel cost. CONCLUSIONS: Reduction of total travel time for the bus mode emerges as the most important element in a program aimed at attracting motorcyclists towards public transport and away from the motorcycle mode.  相似文献   
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Medical error taxonomies are used to report and analyse patient safety incidents. Medical error taxonomies can be generic or domain-specific. In comparing generic and domain-specific medical error taxonomies, the literature compares the information both type of taxonomies classify. There is little evidence the taxonomies have been compared in terms of usability and reliability. Twenty nurses and 21 pharmacists participated in a study comparing the usability and reliability of a generic medical error taxonomy and a medication error taxonomy. The medical error taxonomies utilized were the Patient Safety Event Taxonomy and the NCC MERP Taxonomy of Medication Error. The study found no significant difference in the usability ratings of both taxonomies. The taxonomies required different amount of time to classify patient safety incidents and had significantly different reliability levels. The reliability of the NCC MERP Taxonomy of Medication Error was significantly different when used by nurses and pharmacists. The taxonomy was also preferred by the majority of participants. Some recommendations are made about the design of future medical error taxonomies.  相似文献   
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Environmental Science and Pollution Research - Mixed matrix membranes (MMMs) were fabricated by the hydrothermal synthesis of ordered mesoporous KIT-6 type silica and incorporating in polyimide...  相似文献   
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Several treatment technologies are available for the treatment of palm oil mill wastes. Vermicomposting is widely recognized as efficient, eco-friendly methods for converting organic waste materials to valuable products. This study evaluates the effect of different vermicompost extracts obtained from palm oil mill effluent (POME) and palm-pressed fiber (PPF) mixtures on the germination, growth, relative toxicity, and photosynthetic pigments of mung beans (Vigna radiata) plant. POME contains valuable nutrients and can be used as a liquid fertilizer for fertigation. Mung bean seeds were sown in petri dishes irrigated with different dilutions of vermicomposted POME-PPF extracts, namely 50, 60, and 70% at varying dilutions. Results showed that at lower dilutions, the vermicompost extracts showed favorable effects on seed germination, seedling growth, and total chlorophyll content in mung bean seedlings, but at higher dilutions, they showed inhibitory effects. The carotenoid contents also decreased with increased dilutions of POME-PPF. This study recommends that the extracts could serve as a good source of fertilizer for the germination and growth enhancement of mung bean seedlings at the recommended dilutions.  相似文献   
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This article is the most recent report of polycyclic aromatic hydrocarbons (PAHs) in the Muar River and Pulau Merambong, Peninsular Malaysia. A total of 16 priority pollutant PAHs in addition to methylphenanthrene among alkylated PAHs were analyzed in surface sediments during May 2013. Total PAHs ranged from 212 to 440 and 151 to 412 ng g?1 dw in sediments from the Muar River and the Pulau Merambong, respectively. The Muar River showed an increasing trend of PAH concentrations, while no previous data exist for the Pulau Merambong. Generally, mixed petrogenic and pyrogenic sources of PAHs with predominance of the latter were detected in the study area. Effective management of oil pollution has caused a drastic decrease in petrogenic sources of PAHs.  相似文献   
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