全文获取类型
收费全文 | 114篇 |
免费 | 2篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 69篇 |
废物处理 | 4篇 |
环保管理 | 2篇 |
综合类 | 7篇 |
基础理论 | 23篇 |
污染及防治 | 7篇 |
评价与监测 | 6篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 5篇 |
2022年 | 3篇 |
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2013年 | 7篇 |
2012年 | 9篇 |
2011年 | 6篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 4篇 |
2007年 | 5篇 |
2006年 | 7篇 |
2005年 | 12篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1991年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有119条查询结果,搜索用时 203 毫秒
71.
72.
Emulsion explosives are one type of main industrial explosives. The emergence of the large cartridge emulsion explosives has brought new security incidents. The differential scanning calorimeter (DSC) and the accelerating rate calorimeter (ARC) were selected for the preliminary investigation of the thermal stability of emulsion explosives. The results showed that the initial thermal decomposition temperatures were in the range of 232–239 °C in nitrogen atmosphere (220–232 °C in oxygen atmosphere) in DSC measurements and 216 °C in ARC measurements. The slow cook-off experiments were carried out to investigate the critical temperature of the thermal decomposition (Tc) of the large cartridge emulsion explosives. The results indicated that the larger the diameter of the emulsion explosives, the smaller the Tc is. For the large cartridge emulsion explosives with diameter of 70 mm, the Tc was 170 °C at the heating rate of 3 °C h−1. It is a dangerous temperature for the production of the large cartridge emulsion explosives and it should cause our attention. 相似文献
73.
74.
Runaway reactions by organic peroxides have occurred throughout the world. In this study, we used 1,1,-Di(tert-butylperoxy) cyclohexane (CH) 70 mass% as the main material, which was extensively employed as initiator for styrene in polymerization. Fire extinguishers are the first fire-fighting apparatus when fires occur. If a fire extinguisher has sat idle for a long time, which would cause the extinguishing agent to damp, it cannot achieve the desired effect and be properly handled at the start of the accident, thereby causing more casualties and property losses. CH 70 mass% was employed to mixed with monoammonium phosphate (MAP) for understanding the phenomenon by applying differential scanning calorimetry (DSC). Safety parameters also were carried out for more deeply understanding the basic characteristics for preventing an accident from occurring, in terms of applying CH 70 mass% as the initiator in the manufacturing process. 相似文献
75.
Liviana Leita Alja Margon Iztok Ar?on Marco Contin 《Environmental pollution (Barking, Essex : 1987)》2009,157(6):1862-1866
The interaction between hexavalent chromium Cr(VI), as K2CrO4, and standard humic acids (HAs) in bulk solution was studied using three complementary analytical methods: UV-Visible spectroscopy, X-ray absorption spectroscopy and differential pulse stripping voltammetry. The observed UV-Vis and X-ray absorption spectra showed that, under our experimental conditions, HAs did not induce reduction of Cr(VI) to its trivalent chemical form. The interaction between Cr(VI) and HAs has rather led to the formation of Cr(VI)-HAs micelles via supramolecular chemical processes. The reported results could contribute towards explaining the relative persistence of ecotoxic hexavalent chromium in soils. 相似文献
76.
自反应性化学物质的热危险性评价方法 总被引:18,自引:6,他引:12
笔者进行的研究工作 ,给出了利用C80微量量热仪所测得的自反应性化学物质的热流速曲线 ,从而求解该物质的化学反应动力学参数 ,以及在Semenov模型下求解其自加速分解温度SADT(Self AcceleratingDecompositionTemperature)的方法 ,并将一些有机过氧化物、氧化剂和可燃剂的混合物的自加速分解温度的推算结果与实测值进行了比较。实验证明 ,该推算方法结论准确 ,是一种安全、简便、实用的反应性化学物质热危险性的评价方法 相似文献
77.
过氧化苯甲酰合成工艺热危险性分析 总被引:1,自引:0,他引:1
采用RC1e反应量热仪对过氧化苯甲酰(BPO)合成工艺危险性进行研究,测试不同Na OH溶液初始浓度(1.96 mol/L、3.93 mol/L、7.14 mol/L)下反应的放热历程,获得BPO合成反应过程中的热危险性参数,并采用PHI-TECⅡ绝热加速量热仪对产物进行热稳定性分析,最后评估该反应热风险。结果表明,Na OH浓度为7.14 mol/L时,反应初期放热速率慢,热累积度大,后期反应剧烈,绝热温升(ΔTad)及热失控时工艺反应达到的最高温度(MTSR)最大。热稳定性试验表明,合成的粗产物BPO初始分解温度、活化能、指前因子、最大放热速率到达时间为24 h时的对应温度(TD24)均低于纯BPO。利用合成粗产物BPO的TD24对反应进行危险度评估,该工艺热危险性等级均为5级,工艺危险性大。 相似文献
78.
Despite the concerted efforts by the researchers, government and NGOs to arrest land degradation problems, most agricultural lands of developing countries are still suffering from massive degradation. This study introduces a new strategy, called differential land taxation (DLT), where rural lands are subject to different taxation rates. DLT is determined by rating the magnitude of accord or discord between the recommended and the implemented land management practices. To appraise DLT, opinion of stakeholders, drawn from sample localities of central Ethiopia, were assessed. Most respondents proved that DLT could bring about sustainable land management practices through encouraging conservation-minded peasants while systematically discouraging land abusers. 相似文献
79.
Sexual segregation outside the mating season is common in vertebrates, and has been attributed to sexual differences in predator escape performance in ungulates and fish, but not in birds. Here, we tested the hypothesis that sex- and latitude-specific predator escape performance underlies the differential nonbreeding distribution of western sandpipers (Calidris mauri), a migratory shorebird. Females overwinter further south along the American Pacific coast, creating a latitudinal cline in sex ratio. Escape performance is reduced with increasing body mass, and birds generally carry less fat further south. Western sandpipers with poor escape performance were therefore predicted to prefer southern sites to reduce the risk of mortality posed by predators. Data from four nonbreeding latitudes showed that wing loading, used as an index of escape performance, was overall higher for females, and that it decreased with latitude in both sexes. Within latitudes, wing loading was lower at smaller, and presumably more dangerous, sites. Flight response to a predatory attack was longer in the south. Mortality risk offers a novel and candidate explanation for differential distribution patterns in western sandpipers and possibly other avian migrants. 相似文献
80.
Impressive variation in egg colouration among birds has puzzled evolutionary biologists for a long time. The most frequently
studied selective forces moulding egg colouration—predation and brood parasitism—have either received little empirical support
or may play a role in only a minority of species. A novel hypothesis has suggested that egg colour may be significantly influenced
by sexual selection. Females may deposit a blue-green pigment biliverdin into eggshells instead of using it for themselves
as a powerful antioxidant. By this handicap, females may signal their quality to males, which are then hypothesized to increase
their paternal effort. We experimentally tested the hypothesis in the collared flycatcher (Ficedula albicollis), a species laying blue-green eggs. We cross-fostered clutches between nests to disentangle effects of female/territory quality
and egg colour on paternal effort and nestling quality. The results supported two assumptions of sexual signalling through
egg colour hypothesis: Blue pigment seems to be a limited resource for females, and female quality is positively correlated
with the intensity of the blue-green colour. However, we did not find support for the main prediction of the hypothesis, as
male parental effort parameters (feeding frequencies to nestlings and intensity of nest defence) were unrelated to egg colour.
We discuss possible reasons for the discrepancy between our results and previous correlative analyses that supported the hypothesis
that blue egg colour may be a postmating, sexually selected signal in females. 相似文献