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91.
First principles calculations within the density functional theory framework were carried out to calculate electronic structures and dielectric constant predictions of InGaP2 and InAlP2 compounds. We use three arrangements of these compounds: CuAu-I, CuPt and chalcopyrite ones. Different approximations have been dealt with in order to predict valuable bands gaps energy using DFT calculations. Electronics structure results are promising, due to the good agreement with a number of observable physical-chemistry properties. On the other hand, electron localization function and atom in molecule formalisms have been done to give more insight on the bonding properties. Capabilities that exhibit the InAlP2 in its CuAu-I structure, such as the anisotropy and second harmonic generation, make it promising for an intensive optoelectronic application.  相似文献   
92.
Fatty acid methyl ester (biodiesel) has been identified as biodiesel alternative fuel obtained from renewable sources. Efforts in Egypt are directed toward the development of new non-edible sources. At the forefront of these non-edible sources comes Jatropha curcas oil (JCO) because it has been grown successfully in Egypt using primary treated municipal wastewater for irrigation. Based on previous research findings for the production of biodiesel from (JCO) using heterogeneous catalyst, some kinetic data on the transesterification reaction were provided. This was achieved by conducting the reaction at various temperatures, reaction time, and dose of catalyst and reactant molar ratios. The transesterification reaction was observed with regard to the percent biodiesel yield versus time and the reaction order was found to be a first order reaction rate equation. Techno-economic indicators revealed that the price of biodiesel produced by heterogeneous base catalyzed method was $0.665/L with a gross profit per year of $37,403,643.  相似文献   
93.
Camouflaged cell-membrane-based nanoparticles have gained increasing attention owing to their improved biocompatibility and immunomodulatory properties. Using nanoparticles prepared from the membranes of specific cell types or fusions derived from different cells membranes, their functional performance could be improved in several aspects. Here, cell membranes extracted from breast cancer cells and platelets are used to fabricate a hybrid-membrane vesicle (cancer cell-platelet-fusion-membrane vesicle, CPMV) loaded with therapeutic microRNAs (miRNAs) for the treatment of triple-negative breast cancer (TNBC). A clinically scalable microfluidic platform is presented for fusion of cell membranes. The reconstitution process during synthesis allows for efficient loading of miRNAs into CPMVs. Conditions for preparation of miRNA-loaded CPMVs are systematically optimized and their property of homing to source cells is demonstrated using in vitro experiments and therapeutic evaluation in vivo. In vitro, the CPMVs exhibit significant recognition of their source cells and avoided engulfment by macrophages. After systemic delivery in mice, CPMVs show a prolonged circulation time and site-specific accumulation at implanted TNBC-xenografts. The delivered antimiRNAs are sensitized TNBCs to doxorubicin, resulting in an improved therapeutic response and survival rate. This strategy has considerable potential for clinical translation to improve personalized therapy for breast cancer and other malignancies.  相似文献   
94.
The biostratigraphy, microfacies association, mineralogical interferences, depositional environments and geochemical properties of the Abu Qada Formation, which exposed at Gabal El-Gunna Southeastern Sinai, Egypt were delineated. It belongs to the planktonic foraminiferal Whiteinella archaeocretacea Zone of the Late Cenomanian-Early Turonian and consists of calcareous shale and limestone. The calcareous shale facies is characterized by chlorite, smectite and illite with high concentration of P2O5, Zn, Ni, V, and Cr. The carbonate rocks are characterized by foraminiferal wakestone and bioclastic grainstone. These microfacies associations are characterized by barite with high content of Sr. The facies types with faunal contents, geochemical and mineralogical studies suggest a restricted to shelf lagoon open circulation environment.  相似文献   
95.
Efficient CO2 capture capabilities of activated carbons prepared from natural coal are presented. The preparation method involved simple chemical activation using wet impregnation or dry physical mixing of the raw sample with activating agents like KOH or NaOH. The activated materials were characterized for their structural and textural properties by different analysis techniques. The activated samples exhibited well‐developed porosity, large surface area, and high pore volumes and had other active elements like oxygenated functional groups. These groups modified the surface energy of the resultant samples. The superior performance of the activated carbons was attributed to several factors, including large surface area, presence of narrow micropores, and oxygenated functional groups on the surface.  相似文献   
96.
In this paper, we introduce a novel design for high performance silicon-based Fabry?CPérot cavities and their corresponding design model. According to the design model, the new design shows higher stability, lower insertion loss and higher quality factor Q. Our methodology was based, on one hand, on taking advantage of light reflection and refraction over curved surfaces with curvatures along 2 orthogonal directions, in order to confine the Gaussian beam inside the cavity, thus reducing loss due to beam divergence. Such design enables approaching new limits, where Q-factor is mainly governed by the mirrors reflectance. On the other hand, the use of Bragg reflectors, obtained by DRIE etching enables reaching reflectances above 99%, thus enabling very high Q-factors.  相似文献   
97.
Flame retardants are a growing area of research interest. Nonhalogenated, durable, and nonleachable flame retardants are one of the main strategies used in the research of flame retardant polymers. In this regard, the covalent attachment of phosphorus-containing flame retardants onto cotton fabric has been developed. Two types of reactive phosphorus-containing flame retardants (MKT-1 and MKT-2) have been synthesized and used as a surface coating for cotton fabric. MKT-1 possesses anhydride and acid functionalities that can react with the  OH functionalities in cellulose. In addition, MKT-2 has both acid and organosilicon groups that can also react with the hydroxy group present in cellulose. The structures of the reactive flame retardants (MKT-1 and MKT-2) were characterized using 13C and 31P nuclear magnetic resonance spectroscopy. Thermal properties of the coated and uncoated cotton fabrics were investigated using thermogravimetric analysis. Surface characterization was carried out using scanning electron microscopy and X-ray photoelectron spectroscopy. A standard test method used to evaluate the flammability of blankets (BS 5852) was also applied to characterize the fire retardant properties of the coated and uncoated cotton fabrics studied. Different loadings of MKT-1 and MKT-2 on the fabric (10, 20, and 30% by weight in dimethylformamide solution) were applied in the dip coating process. The cotton fabric coated with 30% MKT-2 does not burn after being subjected to a propane burner for 20 s and also produced the highest char yield (36%) at 500 °C. Inductively coupled plasma–optical emission spectrometry showed that MKT-1 contains 8.23 ± 0.33 P% whereas MKT-2 contains 3.88 ± 0.15 P%. Although MKT-1 possess a higher P content than MKT-2, the additive effect caused by the organosilicon and nitrogen groups present in MK-2 enhance its flame retardant properties. Furthermore, the covalently attached flame retardant materials are durable and do not hydrolyze during washing. The mechanical properties of coated fabrics were characterized by a tensile test and significant change in elongation at break was observed. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47935.  相似文献   
98.
99.
Porous silicon layers manufactured by using (100), 1-5 ohm-cm p-type (boron doped) wafer by electrochemical etching in HF etanol solution. Photoluminescence (PL) spectra of anodically etched silicon obtained for different conditions studied and surface characteristics are investigated by AFM. This study gives a simple way to determine specific surface are of porous silicon which plays a major role with porosity for explaining the blue shift in photoluminescence peak. Properties such as specific surface area, pore size, and pore size distribution, the main surface properties of layer are investigated from AFM data which are important material characteristics in many processing applications. The "specific surface area" (Sspecific) generally defined as the area of solid surface per unit mass of material, solid volume or cross section area. From 3-D reconstructions of AFM data, the surface area and the volume of the porous layer can be estimated directly and volume-surface specific area is calculated. For porous silicon this feature can be defined as the total surface area per volume and given by the unit m2/cm3. The method is simple not need to construct a special set up for measurement and non destructive.  相似文献   
100.
Irrigated agriculture is an important strategic sector in arid and semi-arid regions. Given the large spatial coverage of irrigated areas, operational tools based on satellite remote sensing can contribute to their optimal management. The aim of this study was to evaluate the potential of two spectral indices, calculated from SPOT-5 high-resolution visible (HRV) data, to retrieve the surface water content values (from bare soil to completely covered soil) over wheat fields and detect irrigation supplies in an irrigated area. These indices are the normalized difference water index (NDWI) and the moisture stress index (MSI), covering the main growth stages of wheat. These indices were compared to corresponding in situ measurements of soil moisture and vegetation water content in 30 wheat fields in an irrigated area of Morocco, during the 2012–2013 and 2013–2014 cropping seasons. NDWI and MSI were highly correlated with in situ measurements at both the beginning of the growing season (sowing) and at full vegetation cover (grain filling). From sowing to grain filling, the best correlation (R2 = 0.86; < 0.01) was found for the relationship between NDWI values and observed soil moisture values. These results were validated using a k-fold cross-validation methodology; they indicated that NDWI can be used to estimate and map surface water content changes at the main crop growth stages (from sowing to grain filling). NDWI is an operative index for monitoring irrigation, such as detecting irrigation supplies and mitigating wheat water stress at field and regional levels in semi-arid areas.  相似文献   
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