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101.
In this study, a carbon fiber/vinyl ester-polyurethane interpenetrating polymer network (IPN) laminate composite was fabricated and characterized for the first time. The IPN matrix, consisting of a commercially available vinyl ester and polyurethane, was synthesized via a sequential method with vinyl ester as the rigid phase and polyurethane as the flexible phase. Good compatibility between the two phases in the matrix was achieved and confirmed via differential scanning calorimetry and dynamic mechanical analysis. The thermomechanical response of the IPN matrix was compared with that of an unmodified vinyl ester resin. The presence of the more ductile polyurethane in the IPN matrix depressed the glass transition temperature (from 94 to 84°C), but also served to improve damping response at all frequencies studied. Tensile and flexural tests were performed on the carbon fiber/IPN and carbon fiber/vinyl ester composites to determine their mechanical response. The IPN composite exhibited lower tensile properties than the vinyl ester composite. However, its flexural properties were on par with those of the vinyl ester composite. 相似文献
102.
Delavar M. Bakeri Gh. Hosseini M. Nabian Nima 《Theoretical Foundations of Chemical Engineering》2021,55(1):180-197
Theoretical Foundations of Chemical Engineering - Titania nanotube (TNT) and hydrous manganese oxide (HMO) nanoparticles were synthesized via hydrothermal synthesis and chemical coprecipitation... 相似文献
103.
Nima Ghaderi Joseph Jung Sarah C. Brüningk Ajay Subramanian Lauren Nassour Jeffrey Peacock 《International journal of molecular sciences》2022,23(3)
Radiotherapy is involved in 50% of all cancer treatments and 40% of cancer cures. Most of these treatments are delivered in fractions of equal doses of radiation (Fractional Equivalent Dosing (FED)) in days to weeks. This treatment paradigm has remained unchanged in the past century and does not account for the development of radioresistance during treatment. Even if under-optimized, deviating from a century of successful therapy delivered in FED can be difficult. One way of exploring the infinite space of fraction size and scheduling to identify optimal fractionation schedules is through mathematical oncology simulations that allow for in silico evaluation. This review article explores the evidence that current fractionation promotes the development of radioresistance, summarizes mathematical solutions to account for radioresistance, both in the curative and non-curative setting, and reviews current clinical data investigating non-FED fractionated radiotherapy. 相似文献
104.
The rationale of this study has been to use fluidized beds to crystallize amorphous spray-dried skim milk powders with multiple stages of processing at different temperatures and humidities with the aim of rapidly making mostly crystalline powders. This paper discusses the performance of a multiple-stage fluidized bed dryer, and a combination of crystallization of lactose in spray drying at high humidity (lactose nuclei formation) and subsequent fluidized bed drying. Two different combinations of spray dryer and multi-stage fluidized-bed dryer have been suggested to crystallize lactose in skim milk powder. The results show significant improvements in the crystallinity of the powders. Moisture sorption test and X-ray diffraction analysis were used to assess the crystallinity of the powders. The processed powders that were crystallized in a humid-loop spray drying combined with a two-stage fluidized-bed dryer/crystallizer showed 92% improvement in lower amorphicity by processing at different stages of 70°C, 50% RH and 80°C, 50% RH for 15 minutes. The conventionally spray-dried powders that were crystallized in a three-stage fluidized-bed dryer/crystallizer showed 87% improvement in lower amorphicity (less moisture sorption) by processing at different stages of 60°C, 50% RH; 70°C, 40% RH; and 80°C, 40% RH for 20 minutes. The multiple-stage fluidized bed system showed distinctive potential to crystallize lactose significantly in skim milk powder using an industrial-feasible process. 相似文献
105.
Two new efficient and robust ant colony algorithms are proposed. These algorithms contain two new and reasonable local updating rules that make them more efficient and robust. While going forward from start point to end point of a tour, the ants’ freedom to make local changes on links is gradually restricted. This idea is implemented in two different forms, leaving two new algorithms, KCC-Ants and ELU-Ants. To evaluate the new algorithms, we run them along with the old one on the standard TSP library, where in almost all of the cases the proposed algorithms had better solutions and even for some problem samples found the optimal solution. 相似文献
106.
Formulation for the effect of dissipation of excess pore water pressure on one-dimensional advective-diffusive transport of solutes in clays is presented. The formulation is based on the effect of the rate of consolidation or swelling and excess pore pressure or suction dissipation on transient, nonlinear advective component of transport through clay. One partial differential equation is presented for advective diffusive transport that is dependent upon soil/solute properties and transient hydraulic head gradient, which is calculated from the Terzaghi consolidation equation. Finite difference method is used to solve the system of partial differential equations for consolidation and solute transport. Four hypothetical cases are evaluated to demonstrate the effect of consolidation under loading and swelling under hydraulic gradient on advective-diffusive transport and breakthrough in single and double drainage clay layer. The results show that consolidation in doubly drained clay impacts concentration profiles, but does not significantly impact breakthrough of the diffusive flux. Consolidation under single drainage conditions, significantly impacts the diffusional flux. When drainage path is the same as the diffusional flux, consolidation accelerates transport and breakthrough time can be less than 5% of the diffusional breakthrough time under no consolidation. Swelling under hydraulic gradient application can either accelerate or retard the advective diffusive flux, depending upon the ratio of the effective diffusion coefficient relative to the coefficient of consolidation. Higher the effective diffusion coefficient and lower the coefficient of consolidation result in an increase in the effect of pressure dissipation on transport. 相似文献
107.
Knowledge sharing is an activity through which knowledge, namely, information, skills, or expertise, is exchanged between people, friends, families, communities or organizations. Online knowledge sharing activities are flourishing with the advent of social media and digital life. However, despite of the importance of the online knowledge sharing methods and mechanisms, there is not any comprehensive and systematic study about studying and analyzing its important techniques. Therefore, the main aim of this paper, the comprehensive, detailed, and systematic study, and survey of the state-of-the-art knowledge sharing mechanisms in an online environments is provided. Also, this paper presents a systematic literature review (SLR) on the online knowledge sharing literatures up to end of 2015. We identified 348 papers, which are reduced to 251 primary studies through our paper selection process. Also, the broad overview of the literature provides insights into potential areas for further research. By providing state-of-the-art information, this survey will directly support academics and practicing professionals in their understanding of developments in online knowledge sharing mechanisms and techniques. 相似文献
108.
Over time, architectural ornaments have had a variety of forms that are created from a combination of different types of materials and factors. Brick decorations are one such example, a type of ornament that is often formed on the exterior façade of buildings. Investigating covert rules and brick bonds geometry can reveal a part of the ancient architectural secrets and ways used to reduce the ravages upon new brick façades. Shaped bricks in traditional Iranian architecture directly affect the placement, size and brick arrangement rules. This article is the first attempt to study the effects of geometry and the principal rules of arrangement that help to shape the formation of brick façades specifically, as well as analysing the samples of brick façades taken from monuments, field recordings and discussion with the workmen themselves. The analysis has revealed that permanent rules govern the bonding of brick façades, along with the size and dimensions of the brick effects, which shape the final look of the decoration. 相似文献
109.
Shahab Araghinejad Nima Fayaz Seyed-Mohammad Hosseini-Moghari 《Water Resources Management》2018,32(11):3737-3750
High and low stremflow values forecasting is of great importance in field of water resources in order to mitigate the impacts of flood and drought. Most of water resources models deal with the problem of not being flexible for modeling maximum and minimum flows. To overcome that shortcoming, a combination of artificial neural network (ANN) models is developed in this study for monthly streamflow forecasting. A probabilistic neural network (PNN) is used to classify each of the input-output patterns and afterward, the classified data are forecasted using a modified multi-layer perceptron (MMLP). In addition, the performance of the MLP and generalized regression neural network (GRNN) in streamflow forecasting are investigated and compared to the proposed method. The findings indicate that the R2 associated with the suggested model is 46 and 80% higher compared to MLP and GRNN models, respectively. 相似文献
110.
Veronica Gomez‐Godinez Daryl Preece Linda Shi Nima Khatibzadeh Derrick Rosales Yijia Pan Lie Lei Yingxiao Wang Michael W. Berns 《Microscopy research and technique》2015,78(3):195-199
Cells within the body are subject to various forces; however, the details concerning the way in which cells respond to mechanical stimuli are not well understood. We demonstrate that laser‐induced shockwaves (LIS) combined with biosensors based on fluorescence resonance energy transfer (FRET) is a promising new approach to study biological processes in single live cells. As “proof‐of‐concept,” using a FRET biosensor, we show that in response to LIS, cells release intracellular calcium. With the parameters used, cells retain their morphology and remain viable. LIS combined with FRET permits observation of the cells immediate response to a sudden shear force. Microsc. Res. Tech. 78:195–199, 2015. © 2015 Wiley Periodicals, Inc. 相似文献