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21.
A convenient and effective procedure was developed for the conversion of alcohol to olefin by tosylation and subsequent β-elimination promoted by silica gel in this study. Treatment of the alcohols with p-toluenesulfonyl chloride in pyridine at 0℃ affords tosylates which undergo β-elimination with silica gel in dichloromethane or chloroform at room temperature, yielding olefinswith high productivity.  相似文献   
22.
Carbon isotopic compositions of individual n-alkanols and sterols in modern sediments from the Nansha Islands sea area are measured after derivatization to trimethylsilyl ethers by the new isotopic analytical technique of GC/C/IRMS. The effects of the three added silyl carbon atoms in every alcohol molecule on these compound isotopic compositions and the characteristics of their carbon isotopic compositions are studied. Then their biological sources are discussed using their carbon isotopic compositions. Project supported by the National Natural Science Foundation of China and Project of the Multidisciplinary Oceanographic Expedition of Chinese Academy of Sciences to Nansha Islands.  相似文献   
23.
根据内电解-催化氧化法的应用特点,选用颗粒活性炭作为催化剂的载体,采用浸渍法制备催化剂,并通过用不同催化剂对糖蜜酒精废液COD去除率的比较,确定最佳的催化剂制备条件:Cu(NO3)2浓度为7.5%,浸渍12h,260℃~300℃焙烧活化10~14h;多次使用后的Cu-AC催化剂由催化剂再生技术再生,并应用于糖蜜酒精废液处理。  相似文献   
24.
【目的】确定钝顶螺旋藻(Spirulina platensis)最大程度去除酒精废水中氮、磷的最佳温度、照度和接种量。【方法】通过单因子实验与正交实验研究不同温度、照度和接种量对钝顶螺旋藻去除酒精废水中氮、磷的效果。【结果】单因子实验结果显示,不同温度、照度和接种量对钝顶螺旋藻去除酒精废水中的氮、磷有显著影响(P <0.05)。温度为30℃时,钝顶螺旋藻对酒精废水中总氮和总磷的去除率平均值最高,分别为38.0%和59.0%;照度为3000lx时,钝顶螺旋藻对酒精废水中总氮和总磷的去除率平均值最高,分别为40.9%和60.4%;接种量为(培养基的)50%时,钝顶螺旋藻对酒精废水中总氮的去除率平均值最高,为43.6%;接种量为30%时,钝顶螺旋藻对酒精废水中总磷的去除率平均值达到最高,为62.7%。正交实验结果显示,温度是影响钝顶螺旋藻去除酒精废水中氮、磷的最主要因素。温度30℃、照度2 500~3 000 lx、接种量20%为钝顶螺旋藻去除酒精废水氮和磷的最优组合条件。【结论】适宜的温度、照度和接种量可有效提高酒精废水中氮、磷的去除率。  相似文献   
25.
Oyster extract is an effective bioactivity component. It has abundant nutritional value and antiviral, antitumor and immune defense functions. The role of oyster extract in treating liver injury has been paid more attention. We use Wistar rats to make alcoholic liver disease model through injecting alcohol into rats' stomachs. These rats were randomly divided into five groups: model group, control group, low-dose, middle-dose and high-dose experimental group with a dose of 0.12 g kg-1, 0.40 g kg-1, and 1.20 g kg-1 alcoholic. After nine weeks, serum biomarkers(ALT, AST, TG and TCHO), malondialdehyde(MDA), glutathione(GSH), C3a, C5a, IL-17, TNF-ɑ, anti-MAA-HAS IgG, CD3+, CD4+, CD8+, NK cell activation and zinc content were assessed. The results showed that the serum biomarkers(ALT, AST, TG and TCHO), MDA content, anti-MAA-HSA IgG, serum C3a, C5a IL-17 and TNF-ɑ levels of oyster extract treatment groups were significantly decreased in comparison with model group. On the contrary, GSH showed adverse trend. Serum CD3+, CD4+ and NK cell activation were significantly increased in middle-dose group and high-dose group compared with model group, and there was decrease of CD8+ activity in high-dose group. Plasma Zn level was decreased in model group compared with that in control group. Meanwhile, Mean plasma Zn levels increased dramatically following the dose increase of a given oyster extract.  相似文献   
26.
在水盐体系中,大量Li+的存在,对EDTA络合滴定法测镁有严重的干扰,使滴定结果偏高。采用体积比为1∶9的正丁醇与无水乙醇作掩蔽剂,探究其在不同Li+/Mg2+摩尔比、不同浓度、不同取样量下的适宜加入量,得出混合醇的加入量与Li+/Mg2+摩尔比有较大关系,与溶液浓度、取样量的多少均无明显关系;同时指出在同一Li+/Mg2+摩尔比下混合醇的加入量有个适宜的范围。该方法的相对误差不大于0.3%。对提高含Li+和Mg2+的水盐体系相化学实验研究的可靠性和精度具有重要意义。  相似文献   
27.
An oil-refining plant site located in southern Taiwan has been identified as a petroleum-hydrocarbon [mainly methyl tert-butyl ether (MTBE) and benzene, toluene, ethylbenzene, and xylenes (BTEX)] spill site. In this study, groundwater samples collected from the site were analyzed to assess the occurrence of intrinsic MTBE biodegradation. Microcosm experiments were conducted to evaluate the feasibility of biodegrading MTBE by indigenous microorganisms under aerobic, cometabolic, iron reducing, and methanogenic conditions. Results from the field investigation and microbial enumeration indicate that the intrinsic biodegradation of MTBE and BTEX is occurring and causing the decrease in MTBE and BTEX concentrations. Microcosm results show that the indigenous microorganisms were able to biodegrade MTBE under aerobic conditions using MTBE as the sole primary substrate. The detected biodegradation byproduct, tri-butyl alcohol (TBA), can also be biodegraded by the indigenous microorganisms. In addition, microcosms with site groundwater as the medium solution show higher MTBE biodegradation rate. This indicates that the site groundwater might contain some trace minerals or organics, which could enhance the MTBE biodegradation. Results show that the addition of BTEX at low levels could also enhance the MTBE removal. No MTBE removal was detected in iron reducing and methanogenic microcosms. This might be due to the effects of low dissolved oxygen (approximately 0.3 mg/L) within the plume. The low iron reducers and methanogens (<1.8×103 cell/g of soil) observed in the aquifer also indicate that the iron reduction and methanogenesis are not the dominant biodegradation patterns in the contaminant plume. Results from the microcosm study reveal that preliminary laboratory study is required to determine the appropriate substrates and oxidation-reduction conditions to enhance the biodegradation of MTBE. Results suggest that in situ or on-site aerobic bioremediation using indigenous microorganisms would be a feasible technology to clean up this MTBE-contaminated site.  相似文献   
28.
糖蜜酒精废液生化法的研究进展   总被引:7,自引:0,他引:7  
介绍国内外糖蜜酒精废液生化法的研究现状 ,指出单级工艺很难达到排放标准 ,需要二段以上工艺才能使废液达标排放。  相似文献   
29.
纳豆菌(Bacillus natto)发酵后的条斑紫菜经稀释、离心后上清液用一定浓度的乙醇处理获得醇沉物和醇溶液。将醇沉物去蛋白得到粗多糖,进行抗氧化活性的研究;将醇溶液旋转蒸发得到浸膏,将浸膏按极性大小分相萃取分别得到石油醚相、乙酸乙酯相和正丁醇相浸膏,探讨分相浸膏对金黄色葡萄球菌、枯草芽孢杆菌、四联微球菌的抑菌效果。通过测定多糖和分相浸膏对羟自由基(·OH)和DPPH自由基的清除能力评价其抗氧化能力。结果表明:醇溶物对金黄色葡萄球菌具有抑制作用,且随着浓度的升高各相浸膏对羟基自由基的清除率随之升高,其中,正丁醇相浸膏在质量浓度为0.5 mg/m L时对羟自由基的清除率达到91.6%,说明条斑紫菜经纳豆菌发酵可能产生了活性化合物;与对照组相比,利用纳豆菌发酵紫菜发酵物中多糖提取率增加了0.24%,发酵得到的多糖在质量浓度为5.0 mg/m L时对羟自由基的清除率达到了95.7%。  相似文献   
30.
A non-equilibrium, two-phase, three-component compositional model for the simulation of alcohol flooding has been developed and tested. Inter-phase mass transfer algorithms allow for transfer of all three components at high concentrations and high mass flux rates using a two-film model. The model has been used to simulate alcohol floods where the alcohol has an affinity for either the water-rich phase, or the organic-rich phase. Calibration, using experimental effluent data from an alcohol flood which used a 2-propanol (IPA)-water-tetrachlorethene (PCE) ternary system, indicates that inter-phase mass transfer parameters can be non-unique. Sensitivity studies, completed using the non-equilibrium model for the IPA-water-PCE system, indicate that experimentally derived organic-rich phase composition data should lead to better estimates of the non-wetting phase film thickness. For alcohol flooding experiments where the primary mechanism of non-aqueous phase liquid (NAPL) removal is enhanced dissolution, near-equilibrium conditions may be achieved with NAPL recovery similar for conditions of near-equilibrium and equilibrium. However, for systems where remobilization is the primary mechanism of NAPL recovery, it is expected that although local conditions may approach equilibrium, the resulting NAPL recovery can be significantly lower than would be attained if equilibrium conditions persisted.  相似文献   
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