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31.
This study approaches the interrelation patterns between composition of milk and whey, curd yield, chromaticity, syneresis, and technological quality of Manchega sheep milk using multivariate factor analysis. In addition, the effect of the main husbandry components (flock, prolificacy, season of the year, stage of lactation, and parity) on the common latent factors that define the pattern of variation of Manchega milk was assessed. For this purpose, 1,200 individual Manchega ewe milk samples from 4 different flocks registered under the Protected Designation of Origin Queso Manchego were analyzed (50 ewes/flock). Samples were collected in 2 different seasons of the year (spring and autumn) and at 3 time points per season: early, mid-, and late lactation. The obtained results suggested that curd yield mainly depends on milk composition, and the retention of water in the curd is related to coagulation traits. Thus, composition and moisture content could be useful indicators to assess the efficiency and quality of milk intended for cheesemaking, regardless of the analysis of coagulation properties. Finally, in terms of husbandry, a direct effect of flock and stage of lactation was observed on all analyzed factors, with a lower influence of season and parity.  相似文献   
32.
Amyloid‐β peptides (Aβ) and the protein human serum albumin (HSA) interact in vivo. They are both localised in the blood plasma and in the cerebrospinal fluid. Among other functions, HSA is involved in the transport of the essential metal copper. Complexes between Aβ and copper ions have been proposed to be an aberrant interaction implicated in the development of Alzheimer's disease, where Cu is involved in Aβ aggregation and production of reactive oxygen species (ROS). In the present work, we studied copper‐exchange reaction between Aβ and HSA or the tetrapeptide DAHK (N‐terminal Cu‐binding domain of HSA) and the consequence of this exchange on Aβ‐induced ROS production and cell toxicity. The following results were obtained: 1) HSA and DAHK removed CuII from Aβ rapidly and stoichiometrically, 2) HSA and DAHK were able to decrease Cu‐induced aggregation of Aβ, 3) HSA and DAHK suppressed the catalytic HO. production in vitro and ROS production in neuroblastoma cells generated by Cu–Aβ and ascorbate, 4) HSA and DAHK were able to rescue these cells from the toxicity of Cu–Aβ with ascorbate, 5) DAHK was more potent in ROS suppression and restoration of neuroblastoma cell viability than HSA, in correlation with an easier reduction of CuII–HSA than Cu–DAHK by ascorbate, in vitro. Our data suggest that HSA is able to decrease aberrant CuII–Aβ interaction. The repercussion of the competition between HSA and Aβ to bind Cu in the blood and brain and its relation to Alzheimer's disease are discussed.  相似文献   
33.
MicroRNAs control the differentiation and function of B cells, which are considered key elements in the pathogenesis of systemic lupus erythematosus (SLE). However, a common micro(mi)RNA signature has not emerged since published data includes patients of variable ethnic background, type of disease, and organ involvement, as well as heterogeneous cell populations. Here, we aimed at identifying a miRNA signature of purified B cells from renal and non-renal severe SLE patients of Latin American background, a population known to express severe disease. Genome-wide miRNA expression analyses were performed on naive and memory B cells and revealed two categories of miRNA signatures. The first signature represents B cell subset-specific miRNAs deregulated in SLE: 11 and six miRNAs discriminating naive and memory B cells of SLE patients from healthy controls (HC), respectively. Whether the miRNA was up or down-regulated in memory B cells as compared with naive B cells in HC, this difference was abolished in SLE patients, and vice versa. The second signature identifies six miRNAs associated with specific pathologic features affecting renal outcome, providing a further understanding for SLE pathogenesis. Overall, the present work provided promising biomarkers in molecular diagnostics for disease severity as well as potential new targets for therapeutic intervention in SLE.  相似文献   
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35.
In recent years, interest toward berries has increased (e.g., Myrciaria cauliflora or jaboticaba) because of their high phenolic content (phenolic acids, flavonoids, and anthocyanins) that has been associated with positive effects on consumer health and which play an important role in the antioxidant properties of food. This study analyzed the sorption isotherms, thermodynamic properties of sorption (isosteric heat and Gibbs free energy), and the evolution of the antioxidant capacity during the drying process. The effects of drying temperatures of 40°, 50°C, and 60°C on the antioxidant capacity and thermodynamic properties of sorption were evaluated. The gravimetric static method for sorption isotherm determination over a range of relative humidity levels from 0.10 to 0.90 was used. The sorption isotherms exhibited a Type II behavior, typical for many foods. The Guggenheim, Anderson, and Boer (GAB); Oswin; Peleg; and Lewicki models were used to fit the experimental data, and it was determined that the GAB and Peleg models were most appropriate for describing the sorption curves. The isosteric heat and Gibbs free energy were obtained from the experimental sorption equilibrium. The isosteric heat of adsorption decreased when the moisture content increased, while the Gibbs free energy increased. In addition, the phenolic content and antioxidant capacity increased while drying at 50°C and 60°C, whereas these factors decreased at 40°C. Our results provide the food industry with information concerning the best drying conditions to preserve antioxidant properties.  相似文献   
36.
Van der Waals (vdW) heterostructures combining layered ferromagnets and other 2D crystals are promising building blocks for the realization of ultracompact devices with integrated magnetic, electronic, and optical functionalities. Their implementation in various technologies depends strongly on the development of a bottom-up scalable synthesis approach allowing for realizing highly uniform heterostructures with well-defined interfaces between different 2D-layered materials. It is also required that each material component of the heterostructure remains functional, which ideally includes ferromagnetic order above room temperature for 2D ferromagnets. Here, it is demonstrated that the large-area growth of Fe5−xGeTe2/graphene heterostructures is achieved by vdW epitaxy of Fe5−xGeTe2 on epitaxial graphene. Structural characterization confirms the realization of a continuous vdW heterostructure film with a sharp interface between Fe5−xGeTe2 and graphene. Magnetic and transport studies reveal that the ferromagnetic order persists well above 300 K with a perpendicular magnetic anisotropy. In addition, epitaxial graphene on SiC(0001) continues to exhibit a high electronic quality. These results represent an important advance beyond nonscalable flake exfoliation and stacking methods, thus marking a crucial step toward the implementation of ferromagnetic 2D materials in practical applications.  相似文献   
37.
Characteristics of sheep milk are of great interest for the dairy industry, as almost the totality of production is intended for cheesemaking. However, the existing relationships between these variables are complex. This study assessed composition, hygienic quality, coagulation properties, and curd yield of 1,200 individual Manchega sheep milk samples. The aim was to compare the effect of composition and hygienic quality on coagulation and curdling, and to evaluate the relationship between curd yields and the coagulation process and the effect of other features by using path analysis methodologies. Outcomes proved path analysis to be a useful and effective tool to assess these relationships through direct and indirect paths within the same model. Results showed that the factors that had a direct influence on milk coagulation were lactose concentration, casein content, and initial pH of milk. Contrastingly, somatic cells did not seem to have any effect (direct or indirect) on the coagulation process. Factors that directly affected curd yield were fat content, lactose concentration, casein content, and curd moisture. However, technological parameters showed little effect over curd yield.  相似文献   
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39.
The present work has been conducted in order to develop a novel solution for the heat transfer problem during the continuous casting of steel billets and blooms, by using the element-free Galerkin method under a pseudo-transient moving cross-section slice approach. The transport laws, non-linear aspects and boundary conditions of the initial value problem have been specified. A detailed explanation concerning the characteristics inherent to the application of the element-free Galerkin method to this problem has also been provided. The feasibility and suitability of this novel approach has been verified by comparison with the numerical techniques proposed and the results reported by other researchers as well as an analytical solution of a simple 1-D alloy solidification problem. The results have revealed that this technique could be used successfully in the pseudo transient moving cross-section solution of the heat transfer problem involved in the continuous casting of blooms and square billets.  相似文献   
40.
The monitoring and control of combustion-related emissions is a top priority in many industries. The major methods used to detect combustion gases fall short of practical applications for in-situ measurements in industrial environments involving high temperature and chemical contaminants. The real challenge is not only to develop highly sensitive and selective sensors, but to maintain long-term stability in such aggressive environments. This article presents an overview of a multidisciplinary research effort in ceramic-based chemical sensors, highlighting opportunities as well as challenges. The group of sensors (CO, NO x , O2, and CO2) selected for this article can, in general, be used to determine the state of combustion in a wide variety of applications. Fabrication of sensor probes and their field-test results in automobile engines are also presented.  相似文献   
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