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971.
从受油烟废气污染严重的土壤中分离、筛选出一株具有较强的降解油酸能力的ZFS-1菌株。最佳生长条件为:碳源2.33g/dL、氮源0.53g/dL、摇床转速180r/min。最佳的降解条件:温度33℃,pH7.5,接种体积分数为10%,油酸质量浓度0.79mg/mL,18h后油酸的降解率达到85%以上。 相似文献
972.
Tauer A Bender TO Fleischmann EH Niwa T Jörres A Pischetsrieder M 《Molecular nutrition & food research》2005,49(7):710-715
Conventional fluids for peritoneal dialysis (PD) contain reactive glucose degradation products (GDPs) as a result of glucose breakdown during heat-sterilization. GDPs in PD fluids (PDFs) have been associated with the progressive alteration of the peritoneal membrane during long-term PD by cytotoxic effects and formation of advanced glycation endproducts (AGEs). In this study, we investigated the possible fate of two characteristic GDPs, 3-deoxyglucosone (3-DG) and glyoxal, during PD. In vivo, 3-DG and glyoxal concentrations, which were analyzed by high-performance liquid chromatography (HPLC), decreased in PDFs by 78% and 88% during 4 h of dwell time. The PDFs were then incubated in vitro in the presence of the most important reaction partners of GDPs in the peritoneal cavity. Neither human peritoneal mesothelial cells, human peritoneal fibroblasts, soluble protein, an insoluble collagen surface, nor components of spent dialysate led to a significant reduction of 3-DG or glyoxal after 6 h. Only after long-term incubation, a noticeable decrease of 3-DG was observed (-37% after three weeks), more likely due to spontaneous degradation reaction than formation of advanced glycation endproducts. These results suggest that in the course of PD, 3-DG, and glyoxal are absorbed into the organism and thus might contribute to the systemic pool of reactive carbonyl compounds. 相似文献
973.
Ahoefa Agbagla‐Dohnani Agns Cornu Pierre Nozire Jean‐Michel Besle Jean‐Pierre Dulphy Michel Doreau Elisabeth Grenet 《Journal of the science of food and agriculture》2003,83(5):383-394
The chemical composition, intake, digestibility, ultrastructure and microbial degradation of rice straw from Camargue were compared with barley straw. These variables were observed in two different herbivore digestive ecosystems: the sheep rumen and the donkey caecum. The two straws differed essentially in their ash content, which was three times higher in rice, owing to its silica content. Other chemical components were comparable, except a higher phenolic acids‐to‐lignin ratio in rice. Rice straw was better ingested than barley straw. Organic matter and neutral detergent fibre digestibilities were the same in both straws. Dry matter and cell wall disappearances could be adjusted to the exponential modelling equation with lag time, and differed between animals but not between straws. The sheep rumen had a higher extent of degradation, but the donkey caecum had a higher degradation rate. Statistical analysis revealed that cell‐wall components degradation was similar in the two straws except for ferulic acid, which was more degraded in rice straw. Scanning electron microscopy showed important differences in parenchyma degradation, which was much more effective in rice. Copyright © 2003 Society of Chemical Industry 相似文献
974.
M Teresa Pretel Asuncin Amors M Angeles Botella María Serrano Flix Romojaro 《Journal of the science of food and agriculture》2005,85(1):86-90
The enzymatic activity of four commercial enzymatic preparations (Peelzym I, II, III and IV) on citrus pectin, polygalacturonic acid and carboxymethylcellulose was determined (measured as the decrease in relative viscosity). In addition, the effectiveness of these preparations in the enzymatic degradation of the albedo and the segment membrane from Cimboa fruits was assessed. The highest activity on citrus pectin was shown by Peelzym II, although Peelzym I and IV activities were also elevated, 94.5 ± 6.2% and 88.7 ± 8.3% respectively of Peelzym II activity, and no relevant differences were found between them. Peelzym II also showed the highest activity for polygalacturonic acid, which was approximately 25% more than that of Peelzym I and IV, and more than double that of Peelzym III. Peelzym IV showed 40% more EM‐cellulase activity than Peelzym I, II and III. Segment membrane solution was degraded mainly by the enzymatic preparations Peelzym I and II. Thus, the most effective activities for the degradation of the carpelar membrane from Cimboa were those activities which act mainly on pectin and especially on polygalacturonic acid. However, the albedo was degraded to the greatest extent by Peelzym II and, in turn, the most important activities for albedo degradation were those which act on polygalacturonic acid. In addition, the concentration of the enzymatic preparation for the degradation of the carpelar membrane was lower than that required for albedo degradation. Copyright © 2004 Society of Chemical Industry 相似文献
975.
《International Journal of Hydrogen Energy》2023,48(59):22342-22365
A physicochemical model of a water electrolyzer with a polymer electrolyte membrane (PEM) was developed, taking into account the electrochemical dissolution of an anodic iridium catalyst. The dependencies of the rates of iridium loss and electrolysis voltage increase upon the current density were calculated in order to analyze the effect of the iridium dissolution on degradation of the electrolysis cell (EC) performance. As an estimated characteristic of the techno-economic costs of the electrolysis process, the amount of iridium loss from the anode catalyst layer (as a result of electrochemical dissolution) in the course of the generation of 1 kg of hydrogen was calculated. Data were analyzed and a number of regularities of the iridium dissolution and its influence on the rate of degradation of the EC performance were found. In particular, the most efficient ECs in terms of electrolysis voltage (energy consumption for gas production) are, simultaneously, the most unstable (prone to performance degradation) in relation to the iridium dissolution process. An aim of current requirements for water electrolyzers includes reducing the specific consumption of iridium required for hydrogen generation. 相似文献
976.
《International Journal of Hydrogen Energy》2023,48(71):27599-27610
Simultaneously realizing highly-efficient degradation of microplastics coupled with H2 evolution is urgently demanded to solve the white pollution and energy shortage issues. Herein, we fabricate a series of fragmented hydrophilic homogeneous carbon nitride (TP-PCN) by terminating the polymerization of carbon nitride using iodide ions (I−), which acts as an invisible inhibitor by breaking the π-π bond to reduce the accumulation of ultra-thin layers in PCN to inhibit the polymerization. The H2 evolution rate of resultant photocatalyst could reach 600.3 μmol g−1 h−1 in alkaline polyethylene terephthalate (PET) solution, exhibiting outstanding photocatalytic activity. Meanwhile, the PET was also degraded into small molecules, which were used in agricultural production, food processing and pharmaceuticals. The high photocatalytic activity of the TP-PCN photocatalyst can be ascribed to the promoted hydrophilicity and charge separation ability. This work supplies new insights for the design of functional photocatalysts and developing green technologies to solve environment pollution. 相似文献
977.
笔者提出一种高精度电池寿命损耗评估模型,该模型能充分挖掘厂家提供数据中的有效信息,从而建立起动态循环效率、放电深度(DOD )与实时荷电状态(SOC )应力等因素之间的映射关系。同时,针对采用更精细化的储能模型所引入的非线性项,提出一种基于滚动McCormick松弛方法的优化求解算法,该算法可将原本包含混合整数非线性规划问题转化为混合整数线性规划问题,从而实现优化问题的数值化求解。最后,通过算例证明所提出的精细化电池寿命模型与滚动McCormick求解算法的合理性和优越性。 相似文献
978.
基于FLAC3D有限差分计算平台,建立风力机结构自振频率数值计算模型,并与工程监测的自振频率数据进行对比验证模型的有效性;然后通过嵌入土体刚度衰减模型(DSM),考虑长期循环荷载对地基刚度的影响;探讨不同大小的循环荷载、不同的循环加载次数对海上风力机结构体系自振频率的影响规律,提出自振频率衰减公式;最后结合既有的风力机结构体系自振频率简化计算方法,建立单桩式海上风力机长期自振频率简化评价方法。结果表明,循环荷载的增大、加载次数的增加会导致海上风力机结构体系自振频率较小;风力机结构体系的设计自振频率应偏移3P,以保证海上风力机的长期运营安全。 相似文献
979.
通过共沉淀法制备ZnO/ZnAl2O4纳米异质结光催化剂,利用HRTEM、TEM、XRD、BET、TG-DTA和UV-Vis DRS 测试方法对样品进行表征。在模拟太阳光照射下,通过测定甲基橙溶液的光催化降解率和对大肠杆菌的杀灭率来评价样品的光催化活性。研究催化剂的组成、焙烧温度、催化剂的用量和不同光源对样品光催化活性的影响。结果表明,当原料中Zn与Al摩尔比为1:1.5时,在600℃焙烧所得的催化剂具有最佳光催化活性。在模拟太阳光照射下,在50 min内1.0 g/L光催化剂对甲基橙的降解率达98.5%;在60 min内,在相同条件下对大肠杆菌(106 CFU/mL)的杀菌率达到99.8%。 相似文献
980.
Marko R. Djokic Kevin M. Van Geem Carlo Cavallotti Alessio Frassoldati Eliseo Ranzi Guy B. Marin 《Combustion and Flame》2014
The importance of 1,3-cyclopentadiene (CPD) and cyclopentadienyl (CPDyl) moieties in the growth of polycyclic aromatic hydrocarbons (PAHs) was studied using new experimental data and ab initio calculations. The experimental investigation was performed in a tubular continuous flow pyrolysis reactor under both high (24molN2/molCPD) and low (5molN2/molCPD) nitrogen dilutions, covering a temperature range of 873–1123 K, at a fixed pressure of 1.7 bara. At the most severe conditions up to 84% of CPD is converted, and the amount of PAHs is more than 65 wt%. Major products observed during CPD pyrolysis were benzene, indene, methyl-indenes and naphthalene, in line with previous studies. On-line GC × GC-FID/(TOF-MS) also allowed to quantify minor species (methane, toluene, styrene, phenanthrene, anthracene, etc.), never reported before at this level of accuracy. The new experimental data have been used to further analyze the role of the successive interactions of CPD, indene, and naphthalene as well as the recombination and addition reactions of their resonantly stabilized radicals and refine their kinetics. The results of the modeling study are in good agreement with existing and new experimental observations. 相似文献