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1.
Complete fusion of two selected cells allows for the creation of novel hybrid cells with inherited genetic properties from both original cells.Alternatively,via fusion of a selected cell with a selected vesicle,chemicals or genes can be directly delivered into the cell of interest,to control cellular reactions or gene expression.Here,we demonstrate how to perform an optically controlled fusion of two selected cells or of one cell and one vesicle.Fusion is mediated by laser irradiating plasmonic gold nanoparticles optically trapped between two cells (or a vesicle and a cell) of interest.This hot-particle-mediated fusion causes total mixing of the two cytoplasms and the two cell membranes resulting in formation of a new hybrid cell with an intact cell membrane and enzymatic activity following fusion.Similarly,fusion between a vesicle and a cell results in delivery of the vesicle cargo to the cytoplasm,and after fusion,the cell shows signs of viability.The method is an implementation of targeted drug delivery at the single-cell level and has a great potential for cellular control and design. 相似文献
2.
Modeling for Various Design Options of a Canal System 总被引:1,自引:1,他引:0
Irrigated agriculture is backbone of economy in many countries worldwide, including Pakistan with its large irrigation system.
Systemic Enhancements are periodically implemented to improve the performance of the system. In this paper the performance
of canals has been investigated for various operations. Data regarding discharge of outlets and the canals was collected by
field measurements. Crop-water requirements, bed slope of canals, cross-sectional details, longitudinal profile and outlet
details, were obtained from the Irrigation Department. It was noticed that the performance of canals is not satisfactory under
prevailing conditions. Different operational strategies for change of unlined to lined conditions, different discharge conditions
and outlet dimensions were evaluated using CanalMan model. It was established through extensive research that the performance
of the canals can be improved by lining and changing outlet dimensions. Modified dimensions of outlets for better performance
were estimated by iterative method of optimization. 相似文献
3.
Ishtiaq Hassan Abdul Razzaq Ghumman Hashim Nisar Hashmi Abdul Sattar Shakir 《Civil Engineering and Environmental Systems》2013,30(4):365-376
This study has been carried out to forecast the impact of global warming on the precipitation pattern of Saudi Arabia by the end of year 2100. Simulation has been done using EdGCM model software (with available 8×10 resolution) developed at Columbia University on which there have been produced global precipitation maps for the seasonal and annual averages for the last 5 years (2096–2100). For each map, EdGCM grid values surrounding Saudi Arabia are used as input to one of the tools of Eagle point software called surface modelling (SM). SM is a new approach for downscaling global climate model results. SM software modelled out isohyets at 0.2 mm/day interval. The results indicate that the present pattern of precipitation (more in winter and less in summer) is going to change by almost equal occurrence of precipitation in all seasons for double_CO2 (2CO2) experiment. The 2CO2 experiment indicates an increase of about 16.05% over the annual average precipitation across the country. 相似文献
4.
Sobia Noreen Sara Hasan Shazia Akram Ghumman Syed Nasir Abbas Bukhari Bushra Ijaz Huma Hameed Huma Iqbal Afeefa Aslam Mervat Abdelaziz Mohamed Elsherif Shazia Noureen Hasan Ejaz 《International journal of molecular sciences》2022,23(5)
The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target. 相似文献
5.
This paper presents the results of research regarding the possibilities of the revival of the traditional Bosnian single-family
house. The architectural design, spatial organization, and connection with the natural environment make it a valuable example
of residential architecture. The use of local natural materials such as wood, stone, and adobe brick, brings this typology
back into the limelight. This study illustrates that due to the increasing need to save energy, the importance to use natural
materials, and integration of sustainable design into architectural design processes, our contemporaries turn to past examples
in order to reference benchmarks combined with cutting edge technology for buildings of the future. Because Bosnia has large
wooded areas, and a policy goal is to use local resources, the research aim was to establish if modern prefabricated wooden
houses can reproduce traditional Bosnian architecture while meeting the highest energy efficiency requirements. Many Bosnians
fear that traditional Bosnian architecture will be lost due to new construction, therefore there is opposition against the
harmonization of standards. The solutions for redesigning traditional Bosnian single-family homes to meet energy efficiency
requirements were obtained using the “BuildOpt_VIE” dynamic thermal simulation software. It was used to find optimal solutions
in building physics, along with several variations to be applied during construction of new buildings and reconstruction of
existing buildings. This research sets a foundation for further developments in contemporary individual residences, optimized
according to recent building physics standards. The purpose of this paper is inter alia to show that nothing stands in the
way to harmonize technical guidelines and regulations in the field of energy-efficient buildings in Bosnia and Herzegovina
(B&H), and the adaption of existing norms. Despite the EU requirements as mandated in the Energy Performance of Buildings
Directive, the rich architecture of B&H has potential to fulfill the directive’s conditions. By selecting the best solutions
from the rich architectural tradition of B&H and optimizing the architectural design and building physics, B&H takes a step
towards EU integration. Here, we show the possibility to keep traditional architecture while achieving state of the art energy
efficiency. 相似文献
6.
Is there the potential for an epidemic of variant Creutzfeldt–Jakob disease via blood transfusion in the UK?
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The discovery of three individuals suspected to have contracted variant Creutzfeldt-Jakob disease (vCJD) through blood transfusions has heightened concerns that a secondary epidemic via human-to-human transmission could occur in the UK. The Department of Health responded immediately to this threat by banning those who had received blood transfusions since 1980 from donating blood. In this paper, we conduct a sensitivity analysis to explore the potential size of a blood-borne vCJD epidemic and investigate the effectiveness of public health interventions. A mathematical model was developed together with an expression for the basic reproduction number (R0). The sensitivity of model predictions to unknown parameters determining the transmission of vCJD via infected blood was assessed under pessimistic modelling assumptions. We found that the size of the epidemic (up until 2080) was bounded above by 900 cases, with self-sustaining epidemics (R0>1) also possible; but the scenarios under which such epidemics could arise were found to be biologically implausible. Under optimistic assumptions, public health interventions reduced the upper bound to 250 and further still when only biologically plausible scenarios were considered. Our results support the belief that scenarios leading to large or self-sustaining epidemics are possible but unlikely, and that public health interventions were effective. 相似文献
7.
The incidence of variant Creutzfeldt-Jakob disease (vCJD) in the United Kingdom appears to be in decline, with only four deaths reported this year (to 6 September 2004). However, results of a survey of lymphoreticular tissues have suggested a substantially higher prevalence of vCJD than expected from the clinical data alone. There are two plausible explanations for this discrepancy: first, a proportion of those infected will not develop clinical disease (subclinical infection); and second, the genetic group in which no clinical cases of vCJD have yet occurred is susceptible. Using mathematical models for the primary transmission of bovine spongiform encephalopathy to humans, we explore the impact of these hypotheses on case predictions. Under the first hypothesis, the results suggest relatively few future cases will arise via primary transmission, but that these cases are a small proportion of those infected, with most having subclinical infection. Under the second hypothesis, results suggest a maximum fivefold increase in cases, but this hypothesis is unable to account for the discrepancy between clinical cases and the estimated prevalence. Predictions of future cases of vCJD therefore remain uncertain, particularly given the recent identification of additional cases infected via blood transfusion. 相似文献
8.
Muhammad Masood Ahmad Abdul Razzaq Ghumman Sajjad Ahmad Hashim Nisar Hashmi 《Water Resources Management》2010,24(12):2971-2989
Water resources planning and management requires hydrologic models to estimate runoff from a catchment. For catchments with
limited data, the choice of model and identification of its parameters is very important for development of a direct runoff
hydrograph. A method is presented to determine a unique pair of hydrologic parameters of the Nash Model, number of linear
cascade (n) and storage coefficient (k), using optimization based on Downhill Simplex technique. In this study physical parameters
of the catchment are derived from (SPOT) satellite imageries of the basin using ERDAS software. Four different objective functions
of varying complexity are tested to find the best solution. Weighted root mean square error (RMSE) and Model Efficiency (Nash-Sutcliffe
coefficient) are used to evaluate the model performance. Using the NASH model, a direct surface runoff hydrograph (DSRH) is
developed. Kaha catchment is part of Indus river system and is located in the semi-arid region of Pakistan. This catchment
is dominated by hill torrent flows and is used in this work to demonstrate the applicability of the proposed method. Ten randomly
selected rainfall-runoff events are used for calibration and five events are used for validation. Model results during validation
are very promising with model efficiency exceeding 93% and error in peak discharge under 8%. The sensitivity of the Nash model
output in response to variation in hydrologic parameters n and k is also investigated. When evaluating the hydrologic response
of large catchments, model output is more sensitive to n as compared to k indicating that the runoff diffusion phenomenon
is dominant compared to translation flow effects. 相似文献
9.
Intersection crashes between cars and vulnerable road users (VRUs), such as pedestrians and bicyclists, often result in injuries and fatalities. Advanced driver assistance systems (ADASs) can prevent, or mitigate, these crashes. To derive functional requirements for such systems, an understanding of the underlying contributing factors and the context in which the crashes occur is essential. The aim of this study is to use microscopic and macroscopic crash data to explore the potential of information and warning providing ADASs, and then to derive functional sensor, collision detection, and human–machine interface (HMI) requirements. The microscopic data were obtained from the European project SafetyNet. Causation charts describing contributing factors for 60 car-to-VRU crashes had been compiled and were then also aggregated using the SafetyNet Accident Causation System (SNACS). The macroscopic data were obtained from the Swedish national crash database, STRADA. A total of 9702 crashes were analyzed. The results show that the most frequent contributing factor to the crashes was the drivers’ failure to observe VRUs due to reduced visibility, reduced awareness, and/or insufficient comprehension. An ADAS should therefore help drivers to observe the VRUs in time and to enhance their ability to interpret the development of events in the near future. The system should include a combination of imminent and cautionary collision warnings, with additional support in the form of information about intersection geometry and traffic regulations. The warnings should be deployed via an in-vehicle HMI and according to the likelihood of crash risk. The system should be able to operate under a variety of weather and light conditions. It should have the capacity to support drivers when their view is obstructed by physical objects. To address problems that vehicle-based sensors may face in this regard, the use of cooperative systems is recommended. 相似文献
10.
In this paper, the problem of mining complex temporal patterns in the context of multivariate time series is considered. A new method called the Fast Temporal Pattern Mining with Extended Vertical Lists is introduced. The method is based on an extension of the level‐wise property, which requires a more complex pattern to start at positions within a record where all of the subpatterns of the pattern start. The approach is built around a novel data structure called the Extended Vertical List that tracks positions of the first state of the pattern inside records and links them to appropriate positions of a specific subpattern of the pattern called the prefix. Extensive computational results indicate that the new method performs significantly faster than the previous version of the algorithm for Temporal Pattern Mining; however, the increase in speed comes at the expense of increased memory usage. 相似文献