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1.
重大活动中食品相关产品安全关键控制点分析   总被引:2,自引:0,他引:2  
张秋  邵琳  张淞  项晨 《中国酿造》2020,39(11):208
近年来,中国葡萄酒消费量逐年上升,葡萄酒进口额大幅增长。通过比较分析主要葡萄酒进口来源国在我国的发展现状及趋势,发现法国和澳大利亚两国占据中国进口葡萄酒市场的前两位,且澳洲有赶超之势;智利、西班牙、格鲁吉亚三国对华葡萄酒出口潜力较大,市场份额将进一步提升。与中国缔结双边自贸协定等措施促进了相关国家对华葡萄酒出口,品牌及价格是影响进口葡萄酒消费的重要因素。中国进口葡萄酒市场仍存在认知度不高、价格偏高、假冒伪劣产品等问题,需要进一步降低进口葡萄酒的成本,加强市场监管。  相似文献   
2.
以野菊茎叶为原料,经脱色脱脂后用微波辅助法提取野菊茎叶中的多糖,用苯酚-硫酸法测定多糖的提取量。以料液比、提取温度、提取时间和微波功率为自变量,设计正交试验确定野菊茎叶多糖的最佳提取工艺条件,并通过Fenton体系和DPPH体系测试野菊茎叶多糖的抗氧化活性。结果表明,在料液比1:40(g/mL)、提取温度80℃、提取时间10min、微波功率450 W的条件下野菊茎叶多糖的提取量高达6.32%,微波辅助能快速提取野菊茎叶中的多糖,提取效果显著;野菊茎叶多糖对·OH和DPPH·有清除作用且存在着量效关系,野菊茎叶多糖具有抗氧化活性。  相似文献   
3.
朱悚之 《金属学报》2019,24(6):693-698
目的:探讨人纤维蛋白原(fibrinogen,FIB)对急诊创伤性凝血病患者的临床疗效及相关因素。方法:将2015年6月至2018年6月本院收治的100例严重创伤患者纳入本研究,根据是否创伤性凝血病分为凝血病组(80例)和非凝血病组(20例)。比较凝血病组和非凝血病组患者收住后第1个24 h的急性生理和慢性健康评分(acute physiology and chronic health evaluation II,APACHE II)、创伤严重程度评分(injury severity score,ISS)、低体温及低灌注发生率等指标。采用Logistic多因素回归方法分析严重创伤患者发生创伤性凝血病的相关因素。将80例创伤性凝血病患者随机分为观察组(40例)和对照组(40例)。对照组按照常规诊疗措施治疗,观察组在对照组处理基础上给予人FIB,比较治疗前后观察组和对照组的凝血功能指标,及治疗后的临床用血量、住院时间及病死率。结果:与治疗前相比,治疗后观察组和对照组的凝血酶原时间(prothrombin time,PT)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)及D-二聚体水平降低(P<0.05),FIB水平明显升高(P<0.05)。观察组的红细胞(red blood cell,RBC) 输注量、新鲜冰冻血浆(fresh frozen plasma,FFP)输注量、重症加强护理病房(intensive care unit,ICU)时间及病死率均明显低于对照组,差异具有统计学意义(P<0.05)。创伤性凝血病患者PT>18 s(r=0.623,P=0.024)、APTT>60 s(r=0.722,P=0.018)、凝血酶时间(thrombin time,TT)>15 s(r=0.719,P=0.033)与ISS评分呈正相关。碱缺失(base deficit,BD)≥6(OR=3.678,95%CI=1.065~9.417)、格拉斯哥评分(Glasgow coma scale,GCS)≤8(OR=5.299,95%CI=1.122~8.711)和血小板(platelet,PLT)计数(OR=0.982,95%CI=0.971~0.996)是严重创伤患者发生创伤性凝血病的独立预测因素。结论:人FIB可有效改善创伤性凝血病患者的凝血功能,降低病死率、缩短ICU时间,创伤性凝血病与创伤严重程度、合并休克、低体温和重型颅脑损伤存在一定的相关性。  相似文献   
4.
Nuclear power plant Safety analysis using coupled 3D neutron kinetics/thermal-hydraulic codes technique is increasingly used nowadays. Actually, the use of this technique allows getting less conservatism and more realistic simulations of the physical phenomena. The challenge today is oriented toward the application of this technique to the operating conditions of nuclear research reactors. In the current study, a three-Dimensional Neutron Kinetics and best estimate Thermal-Hydraulic model based upon the coupled PARCS/RELAP5 codes has been developed and applied for a heavy water research reactor. The objective is to perform safety analysis related to design accidents of this reactor types. In the current study two positive reactivity insertion transients are considered, SCRAM protected and self-limiting power excursion cases. The results of the steady state calculations were compared with results obtained from conventional diffusion codes, while transient calculations were assessed using the point kinetic model of the RELAP5 code. Through this study, the applicability and the suitability of using the coupled code technique with respect to the classical models are emphasized and discussed.  相似文献   
5.
目的建立超高效液相色谱法(UPLC)同时测定阿托伐他汀钙原料药中15个杂质含量的方法。方法采用岛津Shim-pack Velox PFPP(2.1 mm×100 mm,1.8μm)色谱柱,以3.9 g/L醋酸铵缓冲液(pH 5.0):乙腈:甲醇:四氢呋喃(无稳定剂)=67:21:6:6为流动相A,3.9 g/L醋酸铵缓冲液(pH 5.0):乙腈:甲醇:四氢呋喃(无稳定剂)=27:61:6:6为流动相B;梯度洗脱,流速0.43 ml/min,检测波长244 nm,柱温35℃,样品室温度10℃;进样量1.8μl。结果阿托伐他汀钙及各杂质峰间分离良好,在0.3~3μg/ml范围内15个杂质均呈良好的线性关系(r均>0.999,n=6),各杂质平均回收率分别为96.3%,99.1%,99.9%,102.4%,96.4%,99.8%,99.4%,104.9%,106.4%,105.4%,100.1%,98.9%,94.7%,94.4%,101.4%,且不同浓度间平行性良好。15个杂质重复性、进样精密度、中间精密度均良好,48 h内均较稳定。此法除对色谱柱要求较高外,耐用性良好。结论本方法简便、快速、分离度好、专属性强,经方法学验证可用于阿托伐他汀钙原料药杂质质量控制。  相似文献   
6.
7.
The demand for biofuels and biochemicals is expected to increase in the future, which will in turn increase the demand for biomass feedstock. Large gasification plants fueled with biomass feedstock are likely to be a key enabling technology in a resource‐efficient, bio‐based economy. Furthermore, the costs for producing biofuels and biochemicals in such plants could potentially be decreased by utilizing inexpensive low‐grade residual biomass as feedstock. This study investigates the usage of shredded tree bark as a feedstock for the production of biomethane in the GoBiGas demonstration plant in Gothenburg, Sweden, based on a 32 MWth industrial dual fluidized bed gasification unit. The plant was operated with bark feedstock for 12 000 hours during the period 2014 to 2018. Data from the measurement campaign were processed using a stochastic approach to establish the plant's mass and energy balances, which were then compared with operation of the plant with wood pellets. For this comparison, an extrapolation algorithm was developed to predict plant performance using bark dried to the same moisture content as wood pellets, ie, 8%w.b. Plant operation with bark feedstock was evaluated for operability, efficiency, and feedstock‐related cost. The gas quality achieved during the test period was similar to that obtained for operation with wood pellets. Furthermore, no significant ash sintering or agglomeration problems were observed more than 750 hours of operation. The calculated biomass‐to‐biomethane efficiency is 43% to 47% (lower heating value basis) for operation with wet bark. However, the predicted biomass‐to‐biomethane efficiency can be increased to 55%–65% for operation with bark feedstock dried to 8% moisture content, with corresponding feedstock costs in the range of 24.2 to 32.7 EUR/MWh; ie, a cost reduction of about 40% compared with wood pellets.  相似文献   
8.
Zinc is an essential nutrient for human health. It plays key roles in maintaining protein structure and stability, serves as catalytic factor for many enzymes, and regulates diverse fundamental cellular processes. Zinc is important in affecting signal transduction and, in particular, in the development and integrity of the immune system, where it affects both innate and adaptive immune responses. The eye, especially the retina‐choroid complex, has an unusually high concentration of zinc compared to other tissues. The highest amount of zinc is concentrated in the retinal pigment epithelium (RPE) (RPE‐choroid, 292 ± 98.5 µg g?1 dry tissue), followed by the retina (123 ± 62.2 µg g?1 dry tissue). The interplay between zinc and inflammation has been explored in other parts of the body but, so far, has not been extensively researched in the eye. Several lines of evidence suggest that ocular zinc concentration decreases with age, especially in the context of age‐related disease. Thus, a hypothesis that retinal function could be modulated by zinc nutrition is proposed, and subsequently trialled clinically. In this review, the distribution and the potential role of zinc in the retina‐choroid complex is outlined, especially in relation to inflammation and immunity, and the clinical studies to date are summarized.  相似文献   
9.
Our primary research hypothesis stands on a simple idea: The evolution of top-rated publications on a particular theme depends heavily on the progress and maturity of related topics. And this even when there are no clear relations or some concepts appear to cease to exist and leave place for newer ones starting many years ago. We implemented our model based on Computer Science Ontology (CSO) and analyzed 44 years of publications. Then we derived the most important concepts related to Cloud Computing (CC) from the scientific collection offered by Clarivate Analytics. Our methodology includes data extraction using advanced web crawling techniques, data preparation, statistical data analysis, and graphical representations. We obtained related concepts after aggregating the scores using the Jaccard coefficient and CSO Ontology. Our article reveals the contribution of Cloud Computing topics in research papers in leading scientific journals and the relationships between the field of Cloud Computing and the interdependent subdivisions identified in the broader framework of Computer Science.  相似文献   
10.
全面分析了我国船舶涂料、集装箱涂料、海洋资源开发及装备的防腐涂料涂装体系以及沿岸基础设施建设的防腐蚀保护涂料的现状及发展趋势。  相似文献   
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