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1.
Concerning the safety problems of conventional Li-ion batteries with liquid electrolytes, it is crucial to develop reliable solid-state electrolytes with high ionic conductivity. Li1+xAlxTi2?x(PO4)3 (LATP, x = 0.3) is regarded as one of the most promising solid electrolytes due to its high ionic conductivity and excellent chemical stability to humidity.Herein, a new strategy is proposed for improving the sintering behavior and enhancing the ionic conductivity of LATP by using LiBO2 as the sintering aid via liquid phase sintering. The as-prepared sample LATP with homogeneous microstructure and high relative density of 97.1% was successfully synthesized, yielding high total ionic conductivity of 3.5 × 10?4 S cm?1 and low activation energy of 0.39 eV at room temperature. It was found that the addition of LiBO2 could effectively enhance the densification and increase the ionic conductivity of LATP electrolyte, proving an effective way to synthesis LATP ceramics by a simple and reliable route.  相似文献   
2.
采用TAB快速测定EMD性能   总被引:2,自引:1,他引:2  
TAB(聚四氟乙烯乙炔黑)是好的导电和粘结合二为一的材料,采用该材料能快速评定EMD的性能。  相似文献   
3.
Based on the previous success of adding ultra-fine carbon–PVA (polyvinyl alcohol) colloid solution to restore performance of weak batteries, a large scale test programme of practical batteries including those used in forklift, golf cart, taxi cab, truck and bus applications from 150 companies was carried out. More than 95% of the tested batteries exhibited excellent recovery in performance parameters including the specific gravity (S.G.), voltage and operation time (Ah capacity). The work reported here includes basic research studies to understand better the beneficial action of the carbon–PVA colloid additive.  相似文献   
4.
Stimulated Raman gain (SRG) spectroscopy using infrared pump pulses with narrow linewidth and a low-noise cw probe infrared laser was proposed. High-resolution Raman spectra of solutions were obtained. The SRG spectra of crystal GaP, benzene, and toluene were measured to confirm the spectral resolution and sensitivity over the terahertz (THz) region. We discuss the polarization dependence of the spectral measurement of carbon tetrachloride. Our system can detect organic molecules in aqueous solutions.  相似文献   
5.
Activation of Ras leads to the constitutive activation of a downstream phosphorylation cascade comprised of Raf-1, mitogen-activated protein kinase (MAPK) kinase, and MAPK. We have developed a yeast-based assay in which the Saccharomyces cerevisiae mating pheromone-induced MAPK pathway relied on co-expression of K-Ras and Raf-1. Radicicol, an antifungal antibiotic, was found to inhibit the K-ras signaling pathway reconstituted in yeast. In K-ras-transformed, rat epithelial, and K-ras-activated, human pancreatic carcinoma cell lines, radicicol inhibited K-Ras-induced hyperphosphorylation of Erk2. In addition, the level of Raf kinase was significantly decreased in radicicol-treated cells, whereas the levels of K-Ras and MAPK remained unchanged. These results suggest that radicicol disrupts the K-Ras-activated signaling pathway by selectively depleting Raf kinase and raises the possibility that pharmacological destabilization of Raf kinase could be a new and powerful approach for the treatment of K-ras-activated human cancers.  相似文献   
6.
Composite graft replacement of the ascending aorta and aortic valve has now become a safe surgical procedure; however, early and late complications still frequently occur. Anastomotic dehiscence after a composite graft replacement is one potentially lethal complication. We herein report two cases of a pseudoaneurysm caused by dehiscence of the right coronary anastomosis, and the proximal aortic anastomosis. A follow-up with an echocardiogram and computed tomography scan was found to be very useful and accurate. We thus successfully treated two cases of pseudoaneurysm using either Bentall's or Carbrol's procedures.  相似文献   
7.
BACKGROUND: Studies in corneal transplant rejection remain important because acute immunologic rejection continues to be the leading cause of human corneal transplant failure. As the permeability of vessels and the neovascularization induce cells infiltration into the graft, we considered the possibility that vascular endothelial growth factor (VEGF), a potent permeability-increasing factor and angiogenesis-mediating factor, could participate in the immune response. METHODS: As the established corneal transplant model for rejection, the corneal transplant between Lewis and Fisher rats has been reported. First, we evaluated VEGF production in the graft by immunohistochemical method in the animal model. Next, we tried to neutralize the effect of VEGF by topical administration of anti-VEGF antibody. We administered anti-VEGF antibody as eye drops for 10 days just after the transplantation of the established animal corneal transplant model. RESULTS: VEGF was strongly produced from the infiltrative cells into the graft. Anti-VEGF antibody significantly suppressed the acute rejection compared with saline or rabbit IgG. CONCLUSIONS: The inhibition of VEGF by topically applied neutralizing antibody is a new potential therapeutic strategy for the treatment of corneal transplantation.  相似文献   
8.
The MR signal of sternal bone marrow was examined in 21 normal volunteers using a sagittal STIR sequence. Craniocaudal phase-encoding with a hand-made positioning device effectively eliminated artifacts due to cardiac pulsation. The sternal bone marrow signal could be classified into three patterns based on the signal distribution. The superior segment of the manubrium showed characteristic age-related changes. This method provided high spatial resolution and excellent bone marrow imaging. Knowledge of a normal marrow signal pattern may be useful for the evaluation of hematological disorders.  相似文献   
9.
We assessed the efficacy of emergency percutaneous cardiopulmonary bypass support (PCPS) in the treatment of patients with acute myocardial infarction complicated by cardiogenic shock. Emergency PCPS was instituted in 21 consecutive patients beginning in 1991. After the stabilization of the hemodynamics, coronary reperfusion was performed by means of coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. Of the seven patients with acute myocardial infarction involving either the left main or two-vessel territories, five survived more than 1 month, but only one patient remained alive and well after 20 months. The main cause of death for this group was low output syndrome. Four of 12 patients with acute left main trunkal occlusion in the catheter laboratory survived and showed a preserved cardiac function (mean followup 28.5 months). The main cause of death for this group was brain damage. Two patients with single-vessel territory acute myocardial infarction underwent PCPS to treat refractory ventricular fibrillation. Both patients were still alive and well at a 12-month followup. Percutaneous cardiopulmonary bypass support successfully stabilized the hemodynamics, allowing time to perform revascularization for all three groups of patients with life-threatening acute myocardial infarction. Recanalization was nevertheless unable to salvage the damaged myocardium in cases of prolonged ischemic time.  相似文献   
10.
Comparative Genomic Hybridization (CGH) is a powerful new method which allows genome-wide mapping of regions with DNA sequence copy number changes (both increases and decreases) in a single experiment without previous knowledge of the locations of the regions of abnormality. CGH is based on in situ hybridization of differentially labeled total genomic tumor DNA and normal DNA to normal human metaphase chromosomes. After hybridization copy number variations among the sequences in the tumor DNA are detected by measuring the tumor/normal fluorescence intensity ratio for each locus in the target chromosomes. Many previously unknown chromosomal regions with relative copy number changes have been detected in various tumors by CGH. Some changes have been identified as genetic markers associated with biological and clinico-pathological characteristics (i.e., histopathological grade, and clinical outcome). We review the published CGH articles and discuss briefly on current progress in CGH analysis to ovarian and uterine cervical cancer in our laboratory.  相似文献   
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