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排序方式: 共有2249条查询结果,搜索用时 15 毫秒
81.
Aaron D. Krabill Hao Chen Dr. Sajjad Hussain Dr. Chao Feng Dr. Ammara Abdullah Prof. Chittaranjan Das Dr. Uma K. Aryal Prof. Carol Beth Post Prof. Michael K. Wendt Prof. Paul J. Galardy Prof. Daniel P. Flaherty 《Chembiochem : a European journal of chemical biology》2020,21(5):712-722
The deubiquitinase (DUB) ubiquitin C-terminal hydrolase L1 (UCHL1) is expressed primarily in the central nervous system under normal physiological conditions. However, UCHL1 is overexpressed in various aggressive forms of cancer with strong evidence supporting UCHL1 as an oncogene in lung, glioma, and blood cancers. In particular, the level of UCHL1 expression in these cancers correlates with increased invasiveness and metastatic behavior, as well as poor patient prognosis. Although UCHL1 is considered an oncogene with potential as a therapeutic target, there remains a significant lack of useful small-molecule probes to pharmacologically validate in vivo targeting of the enzyme. Herein, we describe the characterization of a new covalent cyanopyrrolidine-based UCHL1 inhibitory scaffold in biochemical and cellular studies to better understand the utility of this inhibitor in elucidating the role of UCHL1 in cancer biology. 相似文献
82.
Uzma Arif Nawaz M. Rana Shafia Qureshi Imran Haider Elmasry Yasser Hussain Shafiq 《Theoretical Foundations of Chemical Engineering》2020,54(6):1327-1339
Theoretical Foundations of Chemical Engineering - In this study, the simulations for first-order chemical reactions (constructive and destructive) in the flow of the Casson fluid with... 相似文献
83.
Mohammad Shafiur Rahman M.M. Rashid M.A. Hussain 《Food and Bioproducts Processing》2012,90(2):333-340
A neuro-fuzzy modeling technique was used to predict the effective of thermal conductivity of various fruits and vegetables. A total of 676 data point was used to develop the neuro-fuzzy model considering the inputs as the fraction of water content, temperature and apparent porosity of food materials. The complexity of the data set which incorporates wide ranges of temperature (including those below freezing points) made it difficult for the data to be predicted by normal analytical and conventional models. However the adaptive neuro-fuzzy model (ANFIS) was able to predict conductivity values which closely matched the experimental values by providing lowest mean square error compared to multivariable regression and conventional artificial neural network (ANN) models. This method also alleviates the problem of determining the hidden structure of the neural network layer by trial and error. 相似文献
84.
Hyoung Eun Bae Prof. Kamil Gotfryd Jennifer Thomas Hazrat Hussain Muhammad Ehsan Juyeon Go Prof. Claus J. Loland Dr. Bernadette Byrne Prof. Pil Seok Chae 《Chembiochem : a European journal of chemical biology》2015,16(10):1454-1459
Detergents are an absolute requirement for studying the structure of membrane proteins. However, many conventional detergents fail to stabilise denaturation‐sensitive membrane proteins, such as eukaryotic proteins and membrane protein complexes. New amphipathic agents with enhanced efficacy in stabilising membrane proteins will be helpful in overcoming the barriers to studying membrane protein structures. We have prepared a number of deoxycholate‐based amphiphiles with carbohydrate head groups, designated deoxycholate‐based glycosides (DCGs). These DCGs are the hydrophilic variants of previously reported deoxycholate‐based N‐oxides (DCAOs). Membrane proteins in these agents, particularly the branched diglucoside‐bearing amphiphiles DCG‐1 and DCG‐2, displayed favourable behaviour compared to previously reported parent compounds (DCAOs) and conventional detergents (LDAO and DDM). Given their excellent properties, these agents should have significant potential for membrane protein studies. 相似文献
85.
Muhammad Imran Din Farhan Arshad Zaib Hussain Maria Mukhtar 《Nanoscale research letters》2017,12(1):638
Copper nanoparticles (CuNPs) are of great interest due to their extraordinary properties such as high surface-to-volume ratio, high yield strength, ductility, hardness, flexibility, and rigidity. CuNPs show catalytic, antibacterial, antioxidant, and antifungal activities along with cytotoxicity and anticancer properties in many different applications. Many physical and chemical methods have been used to synthesize nanoparticles including laser ablation, microwave-assisted process, sol-gel, co-precipitation, pulsed wire discharge, vacuum vapor deposition, high-energy irradiation, lithography, mechanical milling, photochemical reduction, electrochemistry, electrospray synthesis, hydrothermal reaction, microemulsion, and chemical reduction. Phytosynthesis of nanoparticles has been suggested as a valuable alternative to physical and chemical methods due to low cytotoxicity, economic prospects, environment-friendly, enhanced biocompatibility, and high antioxidant and antimicrobial activities. The review explains characterization techniques, their main role, limitations, and sensitivity used in the preparation of CuNPs. An overview of techniques used in the synthesis of CuNPs, synthesis procedure, reaction parameters which affect the properties of synthesized CuNPs, and a screening analysis which is used to identify phytochemicals in different plants is presented from the recent published literature which has been reviewed and summarized. Hypothetical mechanisms of reduction of the copper ion by quercetin, stabilization of copper nanoparticles by santin, antimicrobial activity, and reduction of 4-nitrophenol with diagrammatic illustrations are given. The main purpose of this review was to summarize the data of plants used for the synthesis of CuNPs and open a new pathway for researchers to investigate those plants which have not been used in the past. 相似文献
86.
Muhammad Ashraf Bajeer Muhammad Ali Mallah Syed Tufail Hussain Sherazi Muhammad Iqbal Bhanger Shafi Muhammad Nizamani 《Polycyclic Aromatic Compounds》2016,36(3):229-241
This study concerns the investigation of dissipation, adsorption, and degradation of triazophos in different soils from Pakistan. These processes help in the disappearance of pesticide from the environment. Gas chromatography was used for dissipation and adsorption analysis while for degradation study mass spectrometer was used in addition of gas chromatography (GC-MS). The dissipation rate of triazophos in three different soils was 90% over 30 days with average half-life of 9.059 days. From dissipation study it was inferred that rate is variable in each soil due to climatic changes, soil nature and soil-pesticide interactions. Adsorption experiment has revealed that the adsorption of this pesticide to soil follows the pseudo first order kinetic model with rate constant value of 0.479/h and Freundlich isotherm with adsorption capacity of 1.832 mol/g. Degradation study has displayed two major metabolites, one is phosphorothioic acid, S-[2-[(1-cyano-1-methylethyl) amino]-2-oxoethyl] O,O-diethyl ester at retention time of 9.136 and the other is sulfotep at 14.304 min. The leaching potential of triazophos was also calculated from its half-life and organic carbon content present in soil which was 1.688 representing it as non leacher pesticide. 相似文献
87.
Sarah Farrukh X. Fan Arshad Hussain 《Polymer-Plastics Technology and Engineering》2017,56(11):1158-1166
In this study, the CO2 adsorption analysis in cellulose acetate–TiO2- and cellulose acetate–3-aminopropyl-trimethoxysilane TiO2-blended membranes was performed. The membranes were also characterized using scanning electron microscopy and Fourier transform infrared analysis techniques. The adsorption results indicated that 120 and 90°C were considered as optimized temperatures for regeneration of cellulose acetate–TiO2 and cellulose acetate–3-aminopropyl-trimethoxysilane-modified TiO2 membranes. The testing results revealed that adsorption capacity reached maximum at 3.0 bars. Validation of experimental results was performed by pseudo-first-order, second-order and intraparticle diffusion models. The correlation factor R2 represented that the second-order model was fitted well with the experimental data. The intraparticle diffusion model represented that adsorption is not a single-step process. 相似文献
88.
Lipoxygenase and Tocopherol Profiling of Soybean Genotypes Exposed to Electron Beam Irradiation 下载免费PDF全文
Vineet Kumar Anita Rani Priyamvada Jha Lulua Hussain Vijay Pal Vikas Petwal Pramod Kumar Jishnu Dwivedi 《Journal of the American Oil Chemists' Society》2017,94(3):457-463
Electron beam (EB)-irradiation is increasingly being preferred to radioactive-based gamma irradiation in overcoming the constraints that affect the quality of food material. Soybean seeds of 3 soybean genotypes were exposed to 4 doses viz. 4.8, 9.2, 15.3 and 21.2 kGy of EB-irradiation and assessed for the changes in the contents of lipoxygenase isozymes and tocopherol isomers. Densitometry of protein profile revealed decreasing intensity of lipoxygenase with increasing EB dose. All the 3 lipoxygenase isozymes viz. lipoxygenase-1, -2 and -3 registered significant (P < 0.05) increasing reduction with increasing dose; though genotypic variation was noted for the magnitude of reduction at the same dose. Concomitantly, all the 3 genotypes exhibited significant (P < 0.05) decline in α-, γ- and δ-isomers of tocopherol. δ-Tocopherol was the most sensitive to EB-irradiation. EB dose, which caused minimum and maximum decline in total tocopherol content, was genotype-dependent. Decline in vitamin E activity corresponding to the dose, which induced maximum reduction for total lipoxygenase also varied in 3 genotypes. The study showed the usefulness of EB for significant inactivation of off-flavor generating lipoxygenases in soybean, with a non-significant effect on oil content and varied retention of tocopherol isomers and vitamin E activity depending upon genotype. 相似文献
89.
Sugandha Chahal Fathima Shahitha Jahir Hussain Mashitah Mohd Yusoff Mohammad Syaiful Bahari Abdull Rasad Anuj Kumar 《国际聚合物材料杂志》2017,66(3):115-122
The present study focused on the preparation of nanohydroxyapatite (nHA)-coated hydroxyethyl cellulose/polyvinyl alcohol (HEC/PVA) nanofibrous scaffolds for bone tissue engineering application. The electrospun HEC/PVA scaffolds were mineralized via alternate soaking process. FESEM revealed that the nHA was formed uniformly over the nanofibers. The nHA mineralization enhanced the tensile strength and reduced the elongation at breakage of scaffolds. The wettability of the nanofibrous scaffolds was significantly improved. The in vitro biocompatibility of scaffolds was evaluated with human osteosarcoma cells. nHA-coated scaffolds had a favorable effect on the proliferation and differentiation of osteosarcoma cell and could be a potential candidate for bone regeneration. 相似文献
90.
Wastewater treatment by adsorption with electrochemical regeneration using graphite-based adsorbents
H.?M.?A.?Asghar E.?P.?L.?RobertsEmail author S.?N.?Hussain A.?K.?Campen N.?W.?Brown 《Journal of Applied Electrochemistry》2012,42(9):797-807
An innovative technology for wastewater treatment using adsorption and electrochemical regeneration has been developed at the University of Manchester. The process uses a low capacity graphitic adsorbent material (a graphite intercalation compound, NyexTM 1000) which can be regenerated electrochemically. In this study, we investigate the characteristics of a new, partially porous adsorbent material, NyexTM 2000 which offers increased surface area in comparison with NyexTM 1000. NyexTM 2000 was found to have an adsorption capacity of almost three times that of NyexTM 1000. The electrical conductivity of a NyexTM 2000 was found to be double that of NyexTM 1000, enabling improvements in the electrochemical regeneration characteristics. The removal of an anionic azo dye, acid violet 17, from aqueous solution using NyexTM 1000 and 2000 was investigated under various operating conditions. The adsorption of acid violet 17 on NyexTM 2000 was found to be comparatively fast with 75 % of the equilibrium capacity being achieved within 5 min. The parameters affecting the regeneration efficiency including the charge passed, current density, treatment time, adsorbent bed thickness, and pH were investigated. An electrochemical regeneration efficiency of around 100 % was achieved for a fully loaded NyexTM 2000 in a sequential batch electrochemical cell with a regeneration time of 60 min and a charge passed of 100 C g−1 at a current density of 14 mA cm−2. The charge required for electrochemical regeneration was found to be approximately equal to theoretical charge required for complete oxidation of the adsorbed acid violet 17, making process design relatively simple. NyexTM 2000 was found to be an economic adsorbent with relatively small electrical energy consumption required (31 J mg−1 of acid violet 17 treated, compared to 52 J mg−1 of acid violet 17 for NyexTM 1000). Multiple adsorption/regeneration cycles presented no loss in adsorptive capacity and material loses over five adsorption/regeneration cycles. 相似文献