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51.
The ability of a lytic preparation from Streptomyces WL-6 to produce yeast protoplasts was analysed. True protoplasts were found to be produced from strains of the following yeasts: Trigonopsis variabilis, Toruiopsis stellata, Candida puicherrima, Saccharomyces carisbergensis, Saccharomyces cerevisiae and Saccharomyces meilis. The time necessary to obtain 100% protoplasts varied from 35 to 50 min. 相似文献
52.
Multilayer drug-coated granules with a non-uniform distribution of the coating composition specifically the drug loading and the polymer viscosity, across the thickness of the film matrix were prepared by the fluidized bed coating process. The rate and duration of diphenhydramine hydrochloride release from the coated granules can be modified through control of the gradient change in the coating composition across the thickness of the methylcellulose (MC) film matrix. A steeper gradient change across the film matrix resulted in a slower overall release rate. Formulations with gradient drug loading distribution exhibited an extended release time that can be twice as long as that for the control formulation. Gradient layered matrices obtained by sequentially depositing different viscosity grades of MC produced release profiles that differed from film matrices prepared using MC blends. 相似文献
53.
Electron spin resonance (ESR) spectroscopy is able to directly measure the chemical species with unpaired electrons and has been widely used in a number of research fields. This review focused on its application in nutraceutical and food research. Current status of ESR in free radical scavenging capacity estimation, food oxidative stability evaluation, Cu(2+) chelating capacity determination were summarized. Also discussed was the potential of ESR spin-label oximetry technique in examination of lipid peroxidation and oxygen diffusion-concentration products in liposomes, oxygen transport and depletion, and membrane structure and dynamic properties. In addition, ESR application in identifying and estimating irradiated foods including meat, fruits, vegetables, spices, cereal grains, and oil seeds was reviewed. Finally, the potential use of ESR technique in investigating microstructure change, phase transition and viscosity related properties during food formulation, processing, and storage was briefly mentioned, along with its potential in determination of radio-stability of food components. This review may provide some fundamental knowledge of ESR and its application in nutraceutical and food research. 相似文献
54.
Athanassios Fragoulis Kristina Biller Stephanie Fragoulis Dennis Lex Stefan Uhlig Lucy Kathleen Reiss 《International journal of molecular sciences》2021,22(15)
qRT-PCR still remains the most widely used method for quantifying gene expression levels, although newer technologies such as next generation sequencing are becoming increasingly popular. A critical, yet often underappreciated, problem when analysing qRT-PCR data is the selection of suitable reference genes. This problem is compounded in situations where up to 25% of all genes may change (e.g., due to leukocyte invasion), as is typically the case in ARDS. Here, we examined 11 widely used reference genes for their suitability in commonly used models of acute lung injury (ALI): ventilator-induced lung injury (VILI), in vivo and ex vivo, lipopolysaccharide plus mechanical ventilation (MV), and hydrochloric acid plus MV. The stability of reference gene expression was determined using the NormFinder, BestKeeper, and geNorm algorithms. We then proceeded with the geNorm results because this is the only algorithm that provides the number of reference genes required to achieve normalisation. We chose interleukin-6 (Il-6) and C-X-C motif ligand 1 (Cxcl-1) as the genes of interest to analyse and demonstrate the impact of inappropriate normalisation. Reference gene stability differed between the ALI models and even within the subgroup of VILI models, no common reference gene index (RGI) could be determined. NormFinder, BestKeeper, and geNorm produced slightly different, but comparable results. Inappropriate normalisation of Il-6 and Cxcl1 gene expression resulted in significant misinterpretation in all four ALI settings. In conclusion, choosing an inappropriate normalisation strategy can introduce different kinds of bias such as gain or loss as well as under- or overestimation of effects, affecting the interpretation of gene expression data. 相似文献
55.
Neoli Lucyszyn Adriana F. Lubambo Lucy Ono Tatiane A. Jó Clayton F. de Souza Maria Rita Sierakowski 《Food Hydrocolloids》2011
A water-soluble polysaccharide was obtained from Guibourtia hymenifolia seeds in a 54.2% yield (w/w). The Glc:Xyl:Gal molar ratio was 3.3:2.3:1. The methylation results and 1D/2D NMR spectra indicated the presence of xyloglucan (XG), the intrinsic viscosity of which was 665 mL/g. The molar mass (Mw), radius of gyration (Rg), hydrodynamic radius (Rh), and ρ (Rg/Rh) of XG were 8.43 × 105 g/mol, 97 nm, 61 nm, and 1.59, respectively, indicating a random coil and flexible conformation that was subsequently confirmed by the Mark–Houwink constant α (0.70). Atomic force microscopy analysis of XG adsorbed on silicon revealed that the chains are an average of 1.25-nm high, 28.9-nm wide and 131-nm long. Furthermore, a cytotoxicity assay indicated a high CC50 value (>3.3 mg/mL). These results suggest that this biopolymer has potential applications in different food technologies and biotechnological processes. 相似文献
56.
57.
Yuan Shao Lucy Kavi Meleah Boyle Lydia M. Louis Walkiria Pool Stephen B. Thomas Sacoby Wilson Ana M. Rule Lesliam Quiros-Alcala 《Indoor air》2021,31(4):1144-1153
Hairdressers are exposed to particulate matter (PM), a known air pollutant linked to adverse health effects. Still, studies on occupational PM exposures in hair salons are sparse. We characterized indoor air PM concentrations in three salons primarily serving an African/African American (AA) clientele, and three Dominican salons primarily serving a Latino clientele. We also assessed the performance of low-cost sensors (uRAD, Flow, AirVisual) by comparing them to high-end sensors (DustTrak) to conduct air monitoring in each salon over 3 days to quantify work shift concentrations of PM2.5, respirable PM (RPM), and PM10. We observed high spatial and temporal variability in 30-min time-weighted average (TWA) RPM concentrations (0.18–5518 μg/m3). Readings for the uRAD and AirVisual sensors were highly correlated with the DustTrak (R2 = 0.90–0.99). RPM 8-hour TWAs ranged from 18 to 383 µg/m3 for AA salons, and 9–2115 µg/m3 for Dominican salons. Upper 95th percentiles of daily RPM exposures ranged from 439 to 2669 µg/m3. The overall range of 30-min TWA PM2.5 and PM10 concentrations was 0.13–5497 and 0.36-,541 μg/m3, respectively. Findings suggest that hairdressers could be overexposed to RPM during an 8-hour shift. Additional comprehensive monitoring studies are warranted to further characterize temporal and spatial variability of PM exposures in this understudied occupational population. 相似文献
58.
Trutz Theuer Dominik Schäfer Lucy Dittrich Markus Nohl Severin Foit Ludger Blum Rüdiger-A. Eichel L. G. J. de Haart 《化学,工程师,技术》2020,92(1-2):40-44
High-temperature co-electrolysis shows comparable performance to steam electrolysis. Current densities above 1 A cm−2 can be reached between 700 °C and 800 °C. Tailor-made syngas is produced, mainly determined by the reactant ratio. The experimental results are supported by modeling. Durability tests with cathode-supported cells show increased voltage degradation rates during electrolysis compared to fuel cell operation. Nickel depletion is found to be the main cause. 相似文献
59.
Shamanth Nagaraju Sreejith V Lucy J. Gudino Bhushan V. Kadam Ramesha C. K. Joseph Rodrigues 《International Journal of Communication Systems》2020,33(4)
In common practice, sensor nodes are randomly deployed in wireless sensor network (WSN); hence, location information of sensor node is crucial in WSN applications. Localization of sensor nodes performed using a fast area exploration mechanism facilitates precise location‐based sensing and communication. In the proposed localization scheme, the mobile anchor (MA) nodes integrated with localization and directional antenna modules are employed to assist in localizing the static nodes. The use of directional antennas evades trilateration or multilateration techniques for localizing static nodes thereby resulting in lower communication and computational overhead. To facilitate faster area coverage, in this paper, we propose a hybrid of max‐gain and cost‐utility–based frontier (HMF) area exploration method for MA node's mobility. The simulations for the proposed HMF area exploration–based localization scheme are carried out in the Cooja simulator. The paper also proposes additional enhancements to the Cooja simulator to provide directional and sectored antenna support. This additional support allows the user with the flexibility to feed radiation pattern of any antenna obtained either from simulated data of the antenna design simulator, ie, high frequency structure simulator (HFSS) or measured data of the vector network analyzer (VNA). The simulation results show that the proposed localization scheme exhibits minimal delay, energy consumption, and communication overhead compared with other area exploration–based localization schemes. The proof of concept for the proposed localization scheme is implemented using Berkeley motes and customized MA nodes mounted with indigenously designed radio frequency (RF) switch feed network and sectored antenna. 相似文献
60.
Lucy Gloag Milad Mehdipour Dongfei Chen Richard D. Tilley J. Justin Gooding 《Advanced materials (Deerfield Beach, Fla.)》2019,31(48)
Magnetic nanoparticles (MNPs) are of high significance in sensing as they provide viable solutions to the enduring challenges related to lower detection limits and nonspecific effects. The rapid expansion in the applications of MNPs creates a need to overview the current state of the field of MNPs for sensing applications. In this review, the trends and concepts in the literature are critically appraised in terms of the opportunities and limitations of MNPs used for the most advanced sensing applications. The latest progress in MNP sensor technologies is overviewed with a focus on MNP structures and properties, as well as the strategies of incorporating these MNPs into devices. By looking at recent synthetic advancements, and the key challenges that face nanoparticle‐based sensors, this review aims to outline how to design, synthesize, and use MNPs to make the most effective and sensitive sensors. 相似文献