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131.
单粒型甜菜杂交种中甜——吉洮单302的选育 总被引:3,自引:3,他引:0
中甜--吉洮单302为单粒雄性不育杂交种,较丰产、高糖、高抗甜菜褐斑病,耐甜菜根腐病和丛根病。在1996-1998年的轻工国家区域试验(10个试验点)中,有6个点达到高糖型单粒甜菜国家选育标准,且含糖率均达到极显著水平。各达标点年度平均,与统一对照种HYB-13比,根产量提高3.87%,含糖率提高2.06度,产糖量提高19.24%。生产试验各点平均,与HYB-13比,根产量提高12.54%,含糖率提高1.99度,产糖量提高28.80%,褐斑病发病级数降低1.1级,根腐病率降低14.76个百分点。 相似文献
132.
Certified reference materials (CRMs) are prepared from a wide variety of matrices. Water removal is an excellent way of achieving increased matrix lifetime and hence CRM stability. High-speed acousto-optical tuneable filter near-infrared spectrometry (AOTF-NIR) has been implemented for measurement of water content in powder matrix reference materials in amber glass vials. Almost 50,000 spectra were collected from 1300 to 2100 nm with a 2 nm increment for powders of meat, rye grass, potato, cotton seed and sugar beet. The AOTF-NIR instrument was placed in a capping machine, with a measurement frequency of 10–15 vials/min and a trigger signal for reproducible collection of spectra. The calibrants comprised 19 pork meat powder samples equilibrated with different hygrostatic solutions or subjected to oven drying to achieve different water concentrations. Mixtures of powders with different water content were also prepared in order to obtain a calibration range from 0.5 to 8.3% water (m/m). All calibration samples were measured by volumetric Karl Fischer titration (V-KFT), accredited under ISO 17025. The calibrants were then measured by AOTF-NIR together with the samples. Multiplicative scatter correction (MSC) was applied to the absorbance spectra in order to correct for the scattering of light in the different powders and scattering effects from the vials. A partial least squares regression model (PLS) based on two principal components was created and applied for prediction of water content in the samples with a standard error of 0.5% water (m/m). 相似文献
133.
Trehalose Metabolism: From Osmoprotection to Signaling 总被引:1,自引:0,他引:1
Gabriel Iturriaga Ram��n Su��rez Barbara Nova-Franco 《International journal of molecular sciences》2009,10(9):3793-3810
Trehalose is a non-reducing disaccharide formed by two glucose molecules. It is widely distributed in Nature and has been isolated from certain species of bacteria, fungi, invertebrates and plants, which are capable of surviving in a dehydrated state for months or years and subsequently being revived after a few hours of being in contact with water. This disaccharide has many biotechnological applications, as its physicochemical properties allow it to be used to preserve foods, enzymes, vaccines, cells etc., in a dehydrated state at room temperature. One of the most striking findings a decade ago was the discovery of the genes involved in trehalose biosynthesis, present in a great number of organisms that do not accumulate trehalose to significant levels. In plants, this disaccharide has diverse functions and plays an essential role in various stages of development, for example in the formation of the embryo and in flowering. Trehalose also appears to be involved in the regulation of carbon metabolism and photosynthesis. Recently it has been discovered that this sugar plays an important role in plant-microorganism interactions. 相似文献
134.
Ariela V Paula Daniele Urioste Julio C Santos Heizir F de Castro 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(3):281-288
Polysiloxane–polyvinyl alcohol hybrid matrix was prepared by a sol–gel technique and its capacity to bind porcine pancreatic lipase investigated. The loading of 250 units g?1 support was shown to be effective, resulting in an immobilized lipase with high catalytic activity. Both free and immobilized lipases were characterized by determining the activity profile as a function of pH, temperature, substrate concentration and thermal stability. Application of the immobilized lipase in non‐conventional biocatalysis for the synthesis of surfactants and biodiesel was also analyzed. Production of sugar fatty acid esters was found to be dependent on the carbohydrate and the highest molar conversion (50% in 3–4 h of reaction) was achieved for substrates containing fructose and lauric or oleic acids. Biodiesel synthesis from babassu oil and ethanol, propanol or butanol was feasible and regardless of the kind of alcohols, results revealed that the immobilized PPL could efficiently convert triglycerides to fatty acid alkyl esters attaining yields varying from 75 to 95%. Copyright © 2007 Society of Chemical Industry 相似文献
135.
136.
Nutrient loss in the hot water blanching of potatoes 总被引:1,自引:1,他引:0
P. RICE J. D. SELMAN† R. K. ABDUL-REZZAK‡ 《International Journal of Food Science & Technology》1990,25(1):61-65
Measurements have been made from which the apparent diffusivities (Da) were calculated for the loss of total solids, total sugars and reducing sugars in blanching. The variation of apparent mass diffusivity with temperature followed an Arrhenius-type equation. Values for sucrose were estimated by difference from total and reducing sugar measurements. 相似文献
137.
对云南的甘蔗糖厂废糖蜜用水稀释为40Bx°,加磷酸预处理,用酒精除胶体,回收酒精后,再用离子交换树脂脱灰,活性炭脱色脱苦味,制得可食用的糖浆作了较详细的论述 相似文献
138.
Ilaria Massarelli Laura Murgia Anna Maria Bianucci Federica Chiellini Emo Chiellini 《International journal of molecular sciences》2007,8(1):13-28
A practical approach for addressing the computer simulation of protein-carbohydrate interactions is described here. An articulated computational protocol was set up and validated by checking its ability to predict experimental data, available in the literature, and concerning the selectivity shown by the Carbohydrate Recognition Domain (CRD) of the human asialoglycoprotein receptor (ASGP-R) toward Gal-type ligands. Some required features responsible for the interactions were identified. Subsequently the same protocol was applied to monomer sugar molecules that constitute the building blocks for alginates and ulvans. Such sugar polymers may supply a low-cost source of rare sugars with a potential impact on several industrial applications, from pharmaceutical to fine chemical industry. An example of their applicative exploitation could be given by their use in developing biomaterial with adhesion properties toward hepatocytes, through interaction with the ASGP-R. Such a receptor has been already proposed as a target for exogenous molecules, specifically in the case of hepatocytes, for diagnostic and therapeutic purposes. The DOCK5.2 program was used to search optimal locations of the above ligands of interest into CRD binding site and to roughly estimate interaction energies. Finally, the binding ΔG of theoretical protein-ligand complexes was estimated by using the DelPhi program in which the solvation free energy is accounted for with a continuum solvent model, by solving the Poisson-Boltzmann equation. The structure analysis of the obtained complexes and their ΔG values suggest that one of the sugar monomers of interest shows the desired characteristics. 相似文献
139.
Characterization of Early Enzymes Involved in TDP‐Aminodideoxypentose Biosynthesis en Route to Indolocarbazole AT2433 下载免费PDF全文
Dr. Pauline Peltier‐Pain Dr. Shanteri Singh Prof. Jon S. Thorson 《Chembiochem : a European journal of chemical biology》2015,16(15):2141-2146
The characterization of TDP‐α‐d ‐glucose dehydrogenase (AtmS8), TDP‐α‐d ‐glucuronic acid decarboxylase (AtmS9), and TDP‐4‐keto‐α‐d ‐xylose 2,3‐dehydratase (AtmS14), involved in Actinomadura melliaura AT2433 aminodideoxypentose biosynthesis, is reported. This study provides the first biochemical evidence that both deoxypentose and deoxyhexose biosynthetic pathways share common strategies for sugar 2,3‐dehydration/reduction and implicates the sugar nucleotide base specificity of AtmS14 as a potential mechanism for sugar nucleotide commitment to secondary metabolism. In addition, a re‐evaluation of the AtmS9 homologue involved in calicheamicin aminodeoxypentose biosynthesis (CalS9) reveals that CalS9 catalyzes UDP‐4‐keto‐α‐d ‐xylose as the predominant product, rather than UDP‐α‐d ‐xylose as previously reported. Cumulatively, this work provides additional fundamental insights regarding the biosynthesis of novel pentoses attached to complex bacterial secondary metabolites. 相似文献
140.
The aim of this work was to investigate possible improvement of non-sucrose compounds separation from the syrup of raw brown sugar by application of a static mixer in an ultrafiltration process. The static mixer was expected to reduce the concentration polarization and fouling of the membrane. Non-affinated B sugar from the second stage of crystallization, diluted to 60°Bx dry matter, was used for preparing the solution subjected to the ultrafiltration. The cross-flow filtration, at a laboratory level, was carried out on the tubular ceramic membrane (Schumasiv Pall, USA), with a pore diameter of 5 nm. The separation was performed under various working conditions, with and without the presence of static mixer. The effect of turbulence promotion on filtration performances was investigated by using Kenics static mixer (FMX8124-AC, Omega). The process efficiency was quantified through the achieved values of the permeate flux, its colour and dry matter content, while the working factors were: fluid flow-rate, temperature, transmembrane pressure (TMP) and process duration. The positive effects of mixer application were proved. 相似文献