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排序方式: 共有533条查询结果,搜索用时 234 毫秒
91.
Baltasar Peñate Fernando CastellanoAlejandro Bello Lourdes García-Rodríguez 《Energy》2011,36(7):4372-4384
Desalination driven by renewable energies is an interesting technology in isolated coastal areas. Its feasibility and reliability are guaranteed by innumerable designs implemented and experiences carried out, mainly focused on small capacity systems. However, only mature and efficient technologies are suitable for medium or large scale desalination. In the case of seawater desalination, wind-powered reverse osmosis is the most efficient, mature and cost-effective technology. This paper assesses the most suitable design for seawater reverse osmosis desalination driven by off-grid wind energy systems. A high innovative design based on gradual capacity with nominal production of 1000 m3/d is compared to a conventional fixed capacity desalination plant. Due to the intermittent wind resource, the gradual capacity desalination plant is able to fit the available energy and maximize the annual water production. 相似文献
92.
Reproducible results define the very core of scientific integrity in modern research. Yet, legitimate concerns have been raised about the reproducibility of research findings, with important implications for the advancement of science and for public support. With statistical practice increasingly becoming an essential component of research efforts across the sciences, this review article highlights the compelling role of statistics in ensuring that research findings in the animal sciences are reproducible—in other words, able to withstand close interrogation and independent validation. Statistics set a formal framework and a practical toolbox that, when properly implemented, can recover signal from noisy data. Yet, misconceptions and misuse of statistics are recognized as top contributing factors to the reproducibility crisis. In this article, we revisit foundational statistical concepts relevant to reproducible research in the context of the animal sciences, raise awareness on common statistical misuse undermining it, and outline recommendations for statistical practice. Specifically, we emphasize a keen understanding of the data generation process throughout the research endeavor, from thoughtful experimental design and randomization, through rigorous data analysis and inference, to careful wording in communicating research results to peer scientists and society in general. We provide a detailed discussion of core concepts in experimental design, including data architecture, experimental replication, and subsampling, and elaborate on practical implications for proper elicitation of the scope of reach of research findings. For data analysis, we emphasize proper implementation of mixed models, in terms of both distributional assumptions and specification of fixed and random effects to explicitly recognize multilevel data architecture. This is critical to ensure that experimental error for treatments of interest is properly recognized and inference is correctly calibrated. Inferential misinterpretations associated with use of P-values, both significant and not, are clarified, and problems associated with error inflation due to multiple comparisons and selective reporting are illustrated. Overall, we advocate for a responsible practice of statistics in the animal sciences, with an emphasis on continuing quantitative education and interdisciplinary collaboration between animal scientists and statisticians to maximize reproducibility of research findings. 相似文献
93.
A. Bello K. Makgopa M. Fabiane D. Dodoo-Ahrin K. I. Ozoemena N. Manyala 《Journal of Materials Science》2013,48(19):6707-6712
Few-layer graphene was synthesized on a nickel foam template by chemical vapor deposition. The resulting three-dimensional (3D) graphene was loaded with nickel oxide nanostructures using the successive ionic layer adsorption and reaction technique. The composites were characterized and investigated as electrode material for supercapacitors. Raman spectroscopy measurements on the sample revealed that the 3D graphene consisted of mostly few layers, while X-ray diffractometry and scanning electron microscopy revealed the presence of nickel oxide. The electrochemical properties were investigated using cyclic voltammetry, electrochemical impedance spectroscopy, and potentiostatic charge–discharge in aqueous KOH electrolyte. The novelty of this study is the use of the 3D porous cell structure of the nickel foam which allows for the growth of highly conductive graphene and subsequently provides support for uniform adsorption of the NiO onto the graphene. The NF-G/NiO electrode material showed excellent properties as a pseudocapacitive device with a high-specific capacitance value of 783 F g?1 at a scan rate of 2 mV s?1. The device also exhibited excellent cycle stability, with 84 % retention of the initial capacitance after 1000 cycles. The results demonstrate that composites made using 3D graphene are versatile and show considerable promise as electrode materials for supercapacitor applications. 相似文献
94.
Akinluwade Kunle Joseph Adelana Rasaki Adetunji Mosobalaje Adeoye Lasisi Ejibunu Umoru Adeyinka Taofeek Taiwo Peter Kalu Azeez Rommly Dayo Adeyemi Isadare Winston Wole Soboyejo Olusegun Oyeleke Adewoye 《材料科学与工程:中英文B版...》2013,(9):567-570
This study investigates the microstructure of the processed cassava leaves. Standard parts machined from low visible diffusion zone formed in low carbon steel pack cyanided using carbon steel were pack cyanided by high temperature in-situ diffusion of nascent carbon and nitrogen into austenite. Formation of a visible diffusion zone was confirmed after observation with a Reichert-Jung Polyval optical microscope coupled with Zeiss AxioCam ICc 1 camera. High magnification Scanning Electron Microscope (SEM) imaging of the visible diffusion zone was done with a CamScan Series 2 scanning electron microscope. The zone was found variable in depth as measured from a representative position. The structure of all samples consists of ferrite and pearlite as determined by optical and SEM examination. Resulting products were thus both tough and hard suitable for service environments requiring high resistance to both wear and impact failure. 相似文献
95.
Xie X Kwok SY Lu Z Liu Y Cao Y Luo L Zapien JA Bello I Lee CS Lee ST Zhang W 《Nanoscale》2012,4(9):2914-2919
Zinc blende-structured CdTe nanoribbons (NRs) were synthesized for the first time via a two-step process. The electronic, transport, and photoconductive properties of the CdTe NRs were studied systematically. It was revealed that the CdTe NRs showed p-type conductivity, and presented significant photoresponses to visible-NIR (400-800 nm) irradiation with high responsivity and gain. The contribution of the factors such as surface states of NRs, channel length, light intensity, and working bias voltage to the photoresponse characteristics of CdTe NR photodetectors were discussed. Moreover, single CdTe NR-based visible-NIR photodetectors were also demonstrated to have high stability and reliability. 相似文献
96.
Dal Bello B Cocolin L Zeppa G Field D Cotter PD Hill C 《International journal of food microbiology》2012,153(1-2):58-65
In recent years, there has been a particular focus on the application of antimicrobial compounds produced by lactic acid bacteria (LAB) as natural preservatives to control the growth of spoilage and pathogenic bacteria in food. Bacteriocins are antimicrobial peptides which can be added to foods in concentrated forms as food preservatives, e.g. additives, or they can be produced in situ by starters or protective cultures. In this study, twenty Lactococcus lactis bacteriocin producers previously isolated from Italian fermented foods were subjected to a variety of physical and biochemical tests in order to identify those with the greatest potential as starter cultures in cheese production. Of these, four strains isolated from cheese (one nisin Z producer, one nisin A producer and two lacticin 481 producers) which fulfilled the desired technological criteria were assessed for their ability to control Listeria monocytogenes. The subsequent application of these bacteriocinogenic strains as starter cultures in Cottage cheese established that the nisin A producing Lact. lactis 40FEL3, and to a lesser extent the lacticin 481 producers 32FL1 and 32FL3, successfully controlled the growth of the pathogen. This is the first study to directly compare the ability of nisin A, nisin Z and lacticin 481 producing strains to control listerial growth during the manufacture and storage of Cottage cheese. 相似文献
97.
98.
Gluten‐Free Snacks Using Plantain–Chickpea and Maize Blend: Chemical Composition,Starch Digestibility,and Predicted Glycemic Index
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Pamela C. Flores‐Silva Sandra L. Rodriguez‐Ambriz Luis A. Bello‐Pérez 《Journal of food science》2015,80(5):C961-C966
An increase in celiac consumers has caused an increasing interest to develop good quality gluten‐free food products with high nutritional value. Snack foods are consumed worldwide and have become a normal part of the eating habits of the celiac population making them a target to improve their nutritive value. Extrusion and deep‐frying of unripe plantain, chickpea, and maize flours blends produced gluten‐free snacks with high dietary fiber contents (13.7–18.2 g/100 g) and low predicted glycemic index (28 to 35). The gluten‐free snacks presented lower fat content (12.7 to 13.6 g/100 g) than those reported in similar commercial snacks. The snack with the highest unripe plantain flour showed higher slowly digestible starch (11.6 and 13.4 g/100 g) than its counterpart with the highest chickpea flour level (6 g/100 g). The overall acceptability of the gluten‐free snacks was similar to that chili‐flavored commercial snack. It was possible to develop gluten‐free snacks with high dietary fiber content and low predicted glycemic index with the blend of the 3 flours, and these gluten‐free snacks may also be useful as an alternative to reduce excess weight and obesity problems in the general population and celiac community. 相似文献
99.
The effect of partial replacement of NaCl with KCl on the nitrosation process of dry fermented sausages elaborated with L. plantarum + S. carnosus as starter culture was analysed. The Na+/K+ ratio decreased from 4.38 in the control to 0.86 in the modified product. The nitrosation process happened in a quicker and more intense way from the beginning of the process onwards. The chemical conversion percentages (nitrosopigments/total pigments × 100) were higher during the whole ripening process in the modified product. This fact agrees with the highest acidification found in the modified products. Also, a reduced degree of pigment oxidation was found. 相似文献
100.
Effects of pre-treatments on the shrinkage and textural properties of fried sweet potatoes 总被引:1,自引:0,他引:1
This work studied the effects of various pre-treatments (blanching, freezing, air drying, osmotic dehydration and control) on the shrinkage and textural properties of fried sweet potatoes. Sweet potato discs were pre-treated and fried in pure canola oil at 170 °C for 0.5-5 min. Bulk density of the fried samples decreased while porosity increased with frying time. Effect of pre-treatment though not significant on bulk density but was significant (P<0.05) on product porosity. Control samples exhibited less shrinkage than pre-treated samples. Maximum change in diameter of samples ranged between 6.7% and 10.2% depending on pre-treatment. Maximum change in sample thickness was observed by 120 s of frying and the highest value was 18.3%. Pre-treated samples had higher difference in thickness compared to the control samples. Change in sample volume increased with frying time reaching a maximum at 120 s after which it either decreased or levelled off. Generally, pre-treatment improved the textural properties of fried samples in product hardness, springiness, chewiness, cohesiveness and adhesiveness. 相似文献