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161.
Bone scintigraphy has been shown to be sensitive in determining bone involvement in patients with malignancy, but it does not allow the assessment of bone marrow lesions in early disease. The aim of this study was to detect bone marrow invasion using 99Tcm-labelled monoclonal antigranulocyte antibody (AgMoAb) in patients with prostate carcinoma. We studied 56 patients whose mean (+/- S.D.) age was 67 +/- 7 years. The mean prostate-specific antigen level was 6.1 ng ml-1 (normal range 0-5 ng ml-1). Twelve patients were in stage A, 16 in stage B, 17 in stage C and 11 in stage D. Six patients had been receiving chemotherapy and four patients radiotherapy before scanning. Bone scans were obtained 2 h after the intravenous injection of 555 MBq 99Tcm-methylene diphosphonate (99Tcm-MDP). Within a week, bone marrow imaging was performed 4 and 24 h after the injection of 555 MBq 99Tcm-AgMoAb. Metastatic bone lesions were detected on the 99Tcm-MDP scans of 14/56 (25%) patients, of whom one was in stage A, two in stage B, four in stage C and seven in stage D. Hypoactive lesions in bone marrow were detected in 25/56 (45%) patients, of whom two were in stage A, five in stage B, seven in stage C and 11 in stage D. Bone marrow metastases were confirmed in six patients by computed tomography (CT) and magnetic resonance imaging (MRI) and in two patients by marrow aspiration biopsy. A false-positive immune scintigram was found in three patients previously receiving radiotherapy or chemotherapy. We suggest that 99Tcm-AgMoAb scintigraphy is a sensitive procedure for the detection of bone marrow lesions. However, the reason for false-positive and false-negative results should be considered and CT, MRI and marrow biopsy should be performed when clinically necessary.  相似文献   
162.
The role of boric acid–phosphoric acid (BA–PA) impregnation and oxidation on the structure and properties of viscose rayon fibers was examined in air at temperatures ranging from 150 to 250 °C. The results obtained from the measurements of fiber thickness, linear density, X-ray diffraction, thermal analysis (DSC and TGA), and infrared spectroscopy demonstrated that oxidation temperature had a significant influence on the structure and properties of oxidized viscose rayon fibers. Physical transformations were characterized by fiber thickness and linear density values together with color variations and improved burning behavior with progressing oxidation temperature. The DSC analysis showed that BA–PA impregnation enhanced thermal stability and prevented the evolution of volatile by-products by blocking the primary hydroxyl groups. TGA thermograms revealed an enhancement in the char yields. X-ray diffraction analysis showed the loss of cellulose II crystalline structure caused by the decrystallization process initiated by the gradual loss of intermolecular hydrogen bonds. Analysis of IR spectra revealed gradual and continuous loss of intramolecular and intermolecular hydrogen bonding as part of the simultaneously occurring dehydrogenation and dehydration reactions. Analysis of IR data also demonstrated the disturbance of the cellulose II crystalline structure with increasing oxidation temperature in agreement with the results obtained from X-ray diffraction measurements. The formation of C=C bonds attributed to the crosslinked ladder-like structure was also confirmed by the IR spectra.  相似文献   
163.
In this work, zinc oxide semiconducting films belonging to the II-VI group have been produced by successive ionic layer adsorption and reaction (SILAR) method on glass substrates with 10, 15, 20 and 25 cycles at room temperature. Following the deposition, the samples were dried in air at 400 °C for 1 h. The films were characterized by X-ray diffraction, field emission scanning electron microscopy and optical absorption measurement techniques. The X-ray diffractions of the films showed that they are hexagonal in structure. The crystallite size of ZnO films varied between 34 and 38 nm accordingly with the number of SILAR cycles. The material has exhibited direct band gap transition with the band gap values lying in the range between 3.13 and 3.18 eV. The red shift is observed in the absorption edge as the cycles increased. Transmission of the films decreased from 65 to 40% with increasing the number of cycles.  相似文献   
164.
An explosive material, cyanogen azide (CN4) and its univalent and divalent anionic and cationic forms have been studied quantum chemically by using different theoretical approaches. In this study, the structures considered have been screened for their relative stabilities. Also, they have been investigated whether the charged forms play a role in the usual explosion process or any electrical charging during storage cause explosion. Various quantum chemical properties are obtained and discussed. It has been found that the univalent cation and anion and divalent cation formations do not cause much change in the molecular structure as compared to the neutral cyanogen azide molecule, whereas the divalent anionic form exhibits drastic changes in the geometry, resulting in bond cleavage to eliminate nitrogen molecule.  相似文献   
165.
Electroplasmolysis (EP) which is among electrical methods and helps to increase cell permeability was used in this study as a pretreatment on carrot juice production for improving yield. A voltage range of 20–60 V and an application time of 30–90 s were studied using the electroplasmolyzator. Response surface methodology (RSM) was used for determining the appropriate voltage gradient and time that are effective on breakage of vegetable tissues. After the conditions were optimised, carrot juice was produced and compared with untreated control juices on the aspect of yield and some quality characteristics. As a result, yield was increased 10.49% by EP application. Relative to control samples total pectin (14.78%) and total phenolic content (4.73%) have significant increase. In addition by the effect of electrical pretreatment there was an improvement in soluble solid, pulp content and acidity of juices. The results suggested that juice yield and functional properties were improved by EP application.  相似文献   
166.
Obtaining bifunctional electrocatalysts with high activity for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is a main hurdle in the application of rechargeable metal‐air batteries. Earth‐abundant 3d transition metal‐based catalysts have been developed for the OER and ORR; however, most of these are based on oxides, whose insulating nature strongly restricts their catalytic performance. This study describes a metallic Ni‐Fe nitride/nitrogen‐doped graphene hybrid in which 2D Ni‐Fe nitride nanoplates are strongly coupled with the graphene support. Electronic structure of the Ni‐Fe nitride is changed by hybridizing with the nitrogen‐doped graphene. The unique heterostructure of this hybrid catalyst results in very high OER activity with the lowest onset overpotential (150 mV) reported, and good ORR activity comparable to that for commercial Pt/C. The high activity and durability of this bifunctional catalyst are also confirmed in rechargeable zinc‐air batteries that are stable for 180 cycles with an overall overpotential of only 0.77 V at 10 mA?2.  相似文献   
167.
International Journal of Information Security - Deep neural network (DNN) models are widely renowned for their resistance to random perturbations. However, researchers have found out that these...  相似文献   
168.
This study was performed to expand the usage area of phenylene sulfide (PSS) by reducing its cost without deteriorating the material properties. For this purpose, mechanical, thermo-mechanical and abrasion tests were conducted to composite materials obtained by adding carbon fiber (CF), basalt fiber (BF), zeolite, and bentonite into PPS, and the effects of additive type and ratio were examined. For the test samples, fabricated by the melt blending, the fiber content was 10 wt.%, while zeolite, and bentonite ratios were 1, 5, and 10 wt.%. According to tensile and abrasion test results, zeolite, and bentonite improved the properties of fiber-reinforced PPS by showing a synergistic effect. It has been demonstrated in this research that the cost of fiber-reinforced PPS matrix composites, which are widely used in advanced engineering applications, can be reduced by using natural minerals zeolite and bentonite without sacrificing material properties. Findings obtained from mechanical and wear tests, revealed that the composition containing 10, 10, and 80 wt.%, zeolite, CF, and PPS, respectively, exhibited optimum material properties. BF for PPS has been shown to be an alternative reinforcement to CF, as it exhibits the lowest wear rate and better interacts with particles in the matrix.  相似文献   
169.
In this study, static load bearing strength of pin‐connected carbon fiber‐reinforced polyphenylenesulphide (PPS) composites that have [(0°/90°)]3s stacking sequence was investigated. Firstly, the samples were loaded dynamically, and then the same samples were loaded statically. The results obtained from this sequential experiment were compared with the results obtained from samples that were loaded only statically. In addition, the fatigue life and failure mechanisms were investigated with respect to the selection of the geometrical parameters. Dynamic and static loading experiments were performed according to the ASTM STP 749 and ASTM D953 standards, respectively. To obtain optimum load bearing values, the ratio of distance between the edge and hole center to hole diameter (E/D) and ratio of sample width to hole diameter (W/D) has been systematically changed. According to the experimental results, maximum load bearing values have been obtained when E/D ratio was equal to 2. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers  相似文献   
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