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51.
A previous investigation suggested that the use of plasma as the biological fluid for measurement of amphotericin B (AmpB) concentrations greatly underestimates the concentrations of AmpB in the total blood circulation following amphotericin B lipid complex (ABLC) administration to humans. The purpose of this study was to determine if differences in the method used to obtain plasma from whole blood influences the percentage of AmpB recovered in plasma following ABLC incubation in whole blood. ABLC (5 μg AmpB/ml; peak blood concentration observed in rabbits following intravenous bolus of ABLC at a dose of 1 mg/kg) was incubated in whole blood for 5 min at 25°C. These conditions were used to mimic the sample retrieval conditions used when blood is obtained from animals and human patients. Following incubation, plasma was obtained from whole blood using five different methods: (A) Whole blood was centrifuged for 5 min at 23°C, and the plasma was separated; (B) whole blood was stored at 4°C for 18 h, and the plasma was separated by gravity; (C) whole blood was stored at 23°C for 18 h, and the plasma was separated by gravity; (D) whole blood was stored at 37°C for 18 h in a water bath, and the plasma was separated by gravity; and (E) whole blood was stored at 30°C for 18 h in a water bath, and the plasma was separated by gravity. All samples were protected from light throughout the duration of the experiment. AmpB concentration in each plasma sample was determined by high-performance liquid chromatography (HPLC) using an external calibration curve. The whole blood : plasma Amp B concentration ratio and the percentage of AmpB partitioned into plasma following incubation of ABLC in whole blood for each plasma separation procedure was as follows: (A) 6.5 : 1 blood : plasma AmpB concentration ratio, 15.4% ± 1.6% AmpB in plasma; (B) 2.98 : 1 blood : plasma AmpB concentration ratio, 33.6% ± 7.7% AmpB in plasma; (C) 1.5 : 1 blood : plasma AmpB concentration ratio, 67.6% ± 10.3% AmpB in plasma; (D) 1.5 : 1 blood : plasma concentration ratio, 68.1% ± 1.1% AmpB in plasma; and (E) 1.2 : 1 blood : plasma AmpB concentration ratio; 83.4% ± 5.5% AmpB in plasma. These findings suggest that when measurement of AmpB in plasma is required following ABLC administration, incubation of whole blood at 30°C for 18 h appears to be the most effective method.  相似文献   
52.
Smart Manufacturing (SM) a revolutionary paradigm that aims to improve production systems’ performance in terms of quality, time, cost, and flexibility, as well as human and machine decision-making capabilities. Most large enterprises have already taken first steps towards adopting SM. Small and Medium-sized Enterprises (SMEs) on the other hand, are struggling with developing a SM adoption roadmap. Our research builds on the real and perceived needs and challenges faced by manufacturing SMEs and advances the field by developing and evaluating an SME-specific ‘SM adoption framework’. We have employed a multiple case study approach to acknowledge the lessons learned by selected early-adopter SMEs that have recently implemented and deployed SM tools and practices. We propose an SM adoption framework with five vital steps that SMEs interested in SM should follow: (i) identify manufacturing data available within the SME, (ii) readiness assessment of the SME data-hierarchy steps, (iii) developing SM awareness of SME leadership and staff, (iv) develop a SM tailored vision for the SMEs, and (v) identify appropriate SM tools and practices necessary to realise the tailored SM vision. Moreover, the results of the case study analysis enabled us to formulate many generalisations.  相似文献   
53.
ABSTRACT

As early as 1978, the immunosuppressive effect of cyclosporine A (CsA), a metabolite of the fungus Tolypocladium inflatum (), was reported to be effective in inhibiting organ rejection in patients receiving kidney transplants from mismatched cadaver donors () and in the treatment of graft-versus-host disease in patients with acute leukemia following bone marrow transplants (). Today, CsA is still indicated to prevent rejection following solid organ transplantations, prevent and treat graft-vs-host disease following bone marrow transplants, and has also been used in the treatment of autoimmune disease such as psoriasis, rheumatoid arthritis, and nephrotic syndrome (). The effectiveness of CsA is derived from its ability to specifically and reversibly inhibit immunocompetent lymphocytes in the G0 and G1 phase of the cell cycle. The T-helper cells are the main target, but suppression of the T‐suppressor cells also occurs. The production and release of lymphokines, including interleukin-2 are also inhibited (). CsA can be administered intravenously as well as orally in the form of a solution or a soft gelatin capsule. The following review will focus on the evolution of the emulsion-based oral formulations from the first generation as Sandimmune® to the second generation Neoral®, both products of Novartis Pharmaceutical, as well as on the Sandimmune® commercial intravenous formulation. The potential of alternative delivery systems, including micelles, micro- and nanoparticles, and liposomes, will also be discussed.  相似文献   
54.
Organic–inorganic lead halide perovskite materials have recently attracted much attention in the field of optoelectronic devices. Here, a hybrid piezoelectric nanogenerator based on a composite of piezoelectric formamidinium lead halide perovskite (FAPbBr3) nanoparticles and polydimethylsiloxane polymer is fabricated. Piezoresponse force spectroscopy measurements reveal that the FAPbBr3 nanoparticles contain well‐developed ferroelectric properties with high piezoelectric charge coefficient (d33) of 25 pmV−1. The flexible device exhibits high performance with a maximum recordable piezoelectric output voltage of 8.5 V and current density of 3.8 μA cm−2 under periodically vertical compression and release operations. The alternating energy generated from nanogenerators can be used to charge a capacitor and light up a red light‐emitting diode through a bridge rectifier. This result innovatively expands the feasibility of organic–inorganic lead halide perovskite materials for application in a wide variety of high‐performance energy harvesting devices.  相似文献   
55.
Multimedia Tools and Applications - Fog computing is an emerging trend in the healthcare sector for the care of patients in emergencies. Fog computing provides better results in healthcare by...  相似文献   
56.
Wireless Personal Communications - Spam detection in emails tends to be an endless research interest among many researchers and academicians. Even though email communication has become a major role...  相似文献   
57.
Conventionally, Poisson’s equation coupled with 1-D Schrödinger’s equation is solved self-consistently in the triangular quantum well to calculate 2DEG density at the heterointerface. 2DEG density hence derived is a complicated transcendental function which cannot be solved analytically. Therefore, in this work, we use a simple expression for Fermi energy level to develop a compact physics-based 2D-analytical model for 2DEG density. The calculated 2DEG density from this model is validated with earlier reported experimental results. Using this 2DEG density, an expression for I-V characteristics of HEMTs has also been developed. The I-V characteristics of a buffer layer engineered MgZnO/CdZnO HEMT for improved 2DEG density have been analysed for the first time using developed model to the best of our knowledge.  相似文献   
58.
Gel spun polyacrylonitrile/carbon nanotube (PAN/CNT) composite fibers have been produced, and the stress-induced G′ Raman band shifts in the CNTs have been monitored to observe stress transfer during fiber strain. Improvements in CNT quality, CNT dispersion, and post-processing fiber drawing are shown to increase the stress transfer from the matrix to the CNT. Radial breathing mode (RBM) intensity of specific CNT chiralities confirms CNT debundling during fiber processing. During PAN/CNT fiber straining, there reaches a plateau in the CNT G′ downshift, signifying that the stress on the CNT is maintained despite continued straining of the PAN/CNT fiber. Correlating CNT strain with CNT modulus and volume fraction allows for the interfacial shear strength (τi) of the PAN-CNT interface to be determined. The as-spun and fully drawn PAN/CNT-A (99/1) nano composite fibers exhibit τi of 13.1 and 30.9 MPa, respectively, while an improved CNT dispersion (PAN/CNT-A (99.9/0.1)) results in τi equal to 44.3 MPa.  相似文献   
59.
The nano‐scale and micro‐scale inhomogeneity of polyacrylonitrile (PAN) spinning dopes obtained from dynamic light scattering (DLS) experiment is correlated with the tensile strength of the resulting carbon fiber. The nanoscale inhomogeneity was estimated by calculating the diffusion coefficients from the slow relaxation mode of polymer solutions in DLS. The nanoscale inhomogeneity in the spinning dopes was found to be in the range of 1–45 nm. We also demonstrate mean of the count rate (MCR) obtained from DLS of PAN solution as a tool to detect the microscale inhomogeneity in the spinning dope for the first time. The MCR of spinning dopes varied from ~10.0 to 77.5 kcps (kilo‐counts per second). The tensile strength of carbon fibers from the precursor fiber spun from the spinning dopes in this study varied from 3 to 5.2 GPa. Correlation studies show that the microscale inhomogeneity in the spinning dope was a major contributor to the decrease in the tensile strength of carbon fibers in the range of 3–4.5 GPa. Contaminants causing microscale inhomogeneity in PAN powder were removed by using micelles, reverse micelles and frothing. The surfactant treated PAN polymer was characterized using a fourier transform infrared spectroscope, differential scanning calorimeter, and thermal gravimetic analyzer to demonstrate complete removal of surfactants. POLYM. ENG. SCI., 59:478–482, 2019. © 2018 Society of Plastics Engineers  相似文献   
60.
Critical services in a telecommunication network should be continuously provided even when undesirable events like sabotage, natural disasters, or network failures happen. It is essential to provide virtual connections between peering nodes with certain performance guarantees such as minimum throughput, maximum delay or loss. The design, construction and management of virtual connections, network infrastructures and service platforms aim at meeting such requirements.In this paper we consider the network’s ability to survive major and minor failures in network infrastructure and service platforms that are caused by undesired events that might be external or internal. Survive means that the services provided comply with the requirement also in presence of failures. The network survivability is quantified as defined by the ANSI T1A1.2 committee which is the transient performance from the instant an undesirable event occurs until steady state with an acceptable performance level is attained.The assessment of the survivability of a network with virtual connections exposed to link or node failures is addressed in this paper. We have developed both simulation and analytic models to cross-validate our assumptions. In order to avoid state space explosion while addressing large networks we decompose our models first in space by studying the nodes independently and then in time by decoupling our analytic performance and recovery models which gives us a closed form solution. The modeling approaches are applied to both small and real-sized network examples. Three different scenarios have been defined, including single link failure, hurricane disaster, and instabilities in a large block of the system (transient common failure).The results show very good correspondence between the transient loss and delay performance in our simulations and in the analytic approximations.  相似文献   
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