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101.
102.
Mineralizable soil nitrogen and labile soil organic matter in diverse long-term cropping systems 总被引:3,自引:0,他引:3
John T. Spargo Michel A. Cavigelli Steven B. Mirsky Jude E. Maul John J. Meisinger 《Nutrient Cycling in Agroecosystems》2011,90(2):253-266
Sustainable soil fertility management depends on long-term integrated strategies that build and maintain soil organic matter
and mineralizable soil N levels. These strategies increase the portion of crop N needs met by soil N and reduce dependence
on external N inputs required for crop production. To better understand the impact of management on soil N dynamics, we conducted
field and laboratory research on five diverse management systems at a long-term study in Maryland, the USDA- Agricultural
Research Service Beltsville Farming Systems Project (FSP). The FSP is comprised of a conventional no-till corn (Zea mays L.)–soybean (Glycine max L.)–wheat (Triticum aestivum L.)/double-crop soybean rotation (NT), a conventional chisel-till corn–soybean–wheat/soybean rotation (CT), a 2 year organic
corn–soybean rotation (Org2), a 3 year organic corn–soybean–wheat rotation (Org3), and a 6 year organic corn–soybean–wheat–alfalfa
(Medicago sativa L.) (3 years) rotation (Org6). We found that total potentially mineralizable N in organic systems (average 315 kg N ha−1) was significantly greater than the conventional systems (average 235 kg N ha−1). Particulate organic matter (POM)–C and –N also tended to be greater in organic than conventional cropping systems. Average
corn yield and N uptake from unamended (minus N) field microplots were 40 and 48%, respectively, greater in organic than conventional
grain cropping systems. Among the three organic systems, all measures of N availability tended to increase with increasing
frequency of manure application and crop rotation length (Org2 < Org3 ≤ Org6) while most measures were similar between NT
and CT. Our results demonstrate that organic soil fertility management increases soil N availability by increasing labile
soil organic matter. Relatively high levels of mineralizable soil N must be considered when developing soil fertility management
plans for organic systems. 相似文献
103.
Jude A. Okolie Biswa R. Patra Alivia Mukherjee Sonil Nanda Ajay K. Dalai Janusz A. Kozinski 《International Journal of Hydrogen Energy》2021,46(13):8885-8905
The increasing world population, as well as demands for energy and industrial commodities, have led to an overall rise in anthropogenic greenhouse gas emissions. Moreover, demands for fossil fuels and petrochemicals are also gradually escalating in the developing and underdeveloped countries to sustain the transportation sector, industrial power generation and commodity chemical production. To address these challenges and to meet the Paris Agreement on climate change, there has been a growing interest in the development of renewable energy resources. Hydrogen is considered a strong candidate for the next-generation energy infrastructures as an energy carrier and vector, as well as a precursor or auxiliary component for several industrial processes. This review outlines current researches and applications of hydrogen in the processing and upgrading of hydrocarbon fuels, fuel cells, platform chemicals synthesis, pharmaceuticals, aerospace and maritime uses, metallurgy and electronics. Besides, applications of hydrogen as a direct fuel, synthesis of liquid hydrocarbons via Fischer-Tropsch process and syngas fermentation to alcohols are also reviewed. The specific utilization of hydrogen in the metallurgical industry is highlighted for metal reduction and in the oxyhydrogen flame for cutting and welding of metals. Besides, the article also describes the use of hydrogen in pharmaceutical industries for drug discovery. Finally, a variety of socio-economic aspects of hydrogen as a renewable fuel is also outlined in this article. 相似文献
104.
Sivakumar A. Mowlika V. Dhas S. Sahaya Jude Almansour Abdulrahman I. Kumar Raju Suresh Arumugam Natarajan Robert R. Chakraborty Shubhadip Dhas S. A. Martin Britto 《Journal of Materials Science: Materials in Electronics》2021,32(17):22429-22439
Journal of Materials Science: Materials in Electronics - This research work probes into the crystallographic and magnetic structural stability of barium ferrite nanoparticles (BaFe2O4 NPs) at... 相似文献
105.
Erika Larrea Marta Fernandez-Mercado Jos Afonso Guerra-Assuno Jun Wang Ibai Goicoechea Ayman Gaafar Izaskun Ceberio Carmen Lobo Jessica Okosun Anton J. Enright Jude Fitzgibbon Charles H. Lawrie 《International journal of molecular sciences》2020,21(22)
Follicular lymphoma (FL) is a common indolent B-cell lymphoma that can transform into the more aggressive transformed FL (tFL). However, the molecular process driving this transformation is uncertain. In this work, we aimed to identify microRNA (miRNA)-binding sites recurrently mutated in follicular lymphoma patients, as well as in transformed FL patients. Using whole-genome sequencing data from FL tumors, we discovered 544 mutations located in bioinformatically predicted microRNA-binding sites. We then studied these specific regions using targeted sequencing in a cohort of 55 FL patients, found 16 recurrent mutations, and identified a further 69 variants. After filtering for QC, we identified 21 genes with mutated miRNA-binding sites that were also enriched for B-cell-associated genes by Gene Ontology. Over 40% of mutations identified in these genes were present exclusively in tFL patients. We validated the predicted miRNA-binding sites of five of the genes by luciferase assay and demonstrated that the identified mutations in BCL2 and EZH2 genes impaired the binding efficiency of miR-5008 and miR-144 and regulated the endogenous levels of messenger RNA (mRNA). 相似文献
106.
Jude I. Ngadaonye Luke M. Geever Martin O. Cloonan Clement L. Higginbotham 《Journal of Polymer Research》2012,19(3):9822
Novel thermo-sensitive N,N-diethylacrylamide (DEAAm) based copolymer hydrogels were prepared via UV-induced free radical bulk polymerisation. UV polymerisation
was employed to avoid the use of potentially toxic solvents; solution polymerisation has been the most common means for the
preparation of PDEAAm-based hydrogels in the literature to date. The resultant hydrogels were analysed using nuclear magnetic
resonance, Fourier transform infrared spectroscopy and modulated differential scanning calorimetry. Parameters such as the
crosslinking degree and the nature of the incorporated hydrophilic component, N-vinyl-2-pyrrolidone (NVP) or N,N-dimethylacrylamide (DMAAm) were found to impact hydrogel structure, mechanical properties and swelling kinetics. Pulsatile
swelling studies indicated that the hydrogels had thermo-reversible properties which were greatly affected by test temperature,
nature of hydrophilic monomer used and crosslinker content. Aminophylline was selected as a model solute for drug loading
and release studies by thermal deswelling in HCl buffer (pH 1.4) and phosphate buffer media (pH 6.8). The observed lag time
prior to significant drug release from the more crosslinked P(DEAAm-NVP) hydrogels could make them suitable for delayed specific
release in the intestine and potential alternatives to layers or membranes in time-specific and site-specific swelling-controlled
drug delivery systems. 相似文献
107.
108.
The pyrolysis-catalysis of a simulated mixture of plastics representing the plastic mixture found in municipal solid waste has been carried out to determine the influence of process conditions on the production of upgraded fuel oils and chemicals and gases. The catalysts used were spent zeolite from a fluid catalytic cracker (FCC), Y-zeolite and ZSM-5 zeolite. The addition of a catalyst to the process produced a marked increase in gas yield, with more gas (mainly C1–C4 hydrocarbons) being produced as the temperature of the catalyst was raised from 500 °C to 600 °C. The Si/Al ratio of the catalysts influenced the composition of other gases with the more basic catalysts producing more CO and the strongly acidic catalyst producing more H2. The yield of product oil decreased with the addition of the catalysts, but the oil was of significantly lower molecular weight range, containing a product slate of premium fuel range C5–C15 hydrocarbons. In addition, the content of aromatic compounds in the product oil was increased; for example, benzene and toluene accounted for more than 90% of the aromatic content of the oil from the strongly acidic Y-zeolite catalysts. A reaction scheme is proposed for the production of single-ring aromatic compounds via pyrolysis-catalysis of plastics. 相似文献
109.
Lake trout (Salvelinus namaycush) fry were captured in southeastern Lake Michigan for the first time since the species was reintroduced from hatchery stocks in 1965. Spawning apparently occurred in fall 1979 on newly placed limestone riprap covering recently constructed power plant intake and discharge pipelines. Eggs presumably hatched in late February–March, 1980, and 57 fry (22–43 mm total length) were collected April–June, 1980, and three fry (55–62 mm) were collected in August, 1980. 相似文献
110.
Duggan Anne K.; Berlin Lisa J.; Cassidy Jude; Burrell Lori; Tandon S. Darius 《Canadian Metallurgical Quarterly》2009,77(4):788
Home visiting programs for at-risk mothers and their infants have proliferated nationally in recent years, yet experimental studies of home visiting have yielded mixed findings. One promising strategy for explicating the effects of early home visiting is to examine moderators of program impacts. This study assessed the roles of maternal depression and attachment insecurity as moderators of the impacts of Healthy Families Alaska home visiting services for at-risk mothers and their infants. At-risk families (N = 325) were randomly assigned to home visiting or community services as usual (n = 162 and 163, respectively). Maternal depression and attachment insecurity (attachment anxiety and discomfort with trust/dependence) were measured at baseline. Maternal psychosocial and parenting outcomes were measured when children were 2 years old via maternal self-report, observation, and review of substantiated reports of child maltreatment. Maternal depression and attachment insecurity interacted in their moderation of program impacts. For several outcomes, home visiting impacts were greatest for nondepressed mothers with moderate-to-high discomfort with trust/dependence and for depressed mothers with low discomfort with trust/dependence. Implications for practice and policy are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献