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81.
Flame synthesis of carbon nanostructures including nanotubes on galvanized steel was investigated utilizing laminar diffusion flames of different types of fuel. Methane (CH4), propane (C3H8) and acetylene (C2H2) were used as fuels. Distinctive carbon nanostructures were produced depending on fuel types and fuel flow rates. The qualitative and quantitative analysis of many transmission electron microscope (TEM) and scanning electron microscope (SEM) images were performed. Methane produced thin multi wall carbon nanotubes as well as nanorods and nanofibers within the fuel flow rate range of 7.18E-07 m3/s to 9.57E-07 m3/s. Propane yielded nanotubes only at the fuel flow rate of 4.20E-07 m3/s. The nanotubes synthesized by acetylene flames were of different types that included helically coiled and twisted nanotubes. 相似文献
82.
Muhammed Shabbir R. G. Robins 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1968,18(5):129-134
The kinetics of the dissolution of uranium dioxide in nitric acid have been investigated over a range of acid concentration from 0·3 to 37·0 molal. A change in the reduction mechanism for nitric acid is indicated at about 16 molal concentration. A proposed mechanism for the initial rate period of dissolution is consistent with experimental results and with the known thermodynamics of the system. 相似文献
83.
This work presents two dual polarized proximity‐fed monostatic patch antennas with improved interport isolation for 2.4 GHz industrial, scientific and medical band same frequency full duplex wireless applications. The presented antennas achieves the high interport decoupling through intrinsic isolation of the polarization diversity in conjunction with a simple single‐tap and two‐taps self‐interference cancellation (SIC) topologies. The polarization diversity isolation is achieved through two perpendicular microstrip feeds for proximity feeding to excite orthogonal polarization mode for transmit (Tx) and receive (Rx) modes. The prototype for proposed antenna with integrated single‐tap and two‐taps SIC circuit is tested to record its interport isolation, impedance bandwidths and gains for both Tx and Rx ports. The implemented antenna with single‐tap SIC circuit demonstrates 10 dB return‐loss bandwidth of ≥100 MHz for both Tx and Rx ports. The measured isolation exceeds 40 dB over the 40 MHz bandwidth. Moreover, the recorded peak isolation is better than 74 dB for implemented antenna prototype. Furthermore, the 40 MHz bandwidth with 40 dB isolation can be tuned with the help of SIC‐tap as demonstrated through the experimental results. The measured gain levels are around 4.6 dBi for both Tx and Rx port. The same antenna structure with integrated two‐taps SIC topology features better than 55 dB isolation within 10 dB return loss bandwidth of 100 MHz. The peak isolation exceeds 97 dB and isolation levels are better than 60 and 80 dB over 50 and 20 MHz bandwidths, respectively, for presented antenna with two‐taps SIC configuration. The compact antenna offers comparatively wider impedance and isolation bandwidth with improved SIC levels compared to previous designs. 相似文献
84.
An Efficient Shewhart‐Type Control Chart to Monitor Moderate Size Shifts in the Process Mean in Phase II 下载免费PDF全文
Javid Shabbir Wajid Hussain Awan 《Quality and Reliability Engineering International》2016,32(5):1597-1619
According to Shewhart, control charts are not very sensitive to small and moderate size process shifts that is why those are less likely to be effective in Phase II. So to monitor small or moderate size process shifts in Phase II, cumulative sum (CUSUM) and exponentially weighted moving average (EWMA) control charts are considered as alternate of Shewhart control charts. In this paper, a Shewhart‐type control chart is proposed by using difference‐in‐difference estimator in order to detect moderate size shifts in process mean in Phase II. The performance of the proposed control chart is studied for known and unknown cases separately through a detailed simulation study. For the unknown case, instead of using reference samples of small sizes, large size reference sample(s) is used as we can see in some of nonparametric control chart articles. In an illustrative example, the proposed control charts are constructed for both known and unknown cases along with Shewhart ‐chart, classical EWMA, and CUSUM control charts. In this application, the proposed chart is found comprehensively better than not only Shewhart ‐chart but also EWMA and CUSUM control charts. By comparing average run length, the proposed control chart is found always better than Shewhart ‐chart and in general better than classical EWMA and CUSUM control charts when we have relatively higher values of correlation coefficients and detection of the moderate shifts in the process mean is concerned. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
85.
Mazhar Yaqub Nasir Abbas Muhammad Riaz Javid Shabbir 《Quality and Reliability Engineering International》2016,32(7):2491-2497
The presence of variation cannot be avoided in different kinds of manufacturing and non‐manufacturing processes. A better understanding of the causes of variability in any process is necessary to improve the process. Control chart is a very frequently used tool for checking whether the process parameters are stable or not. The current study devises a sampling technique, named as modified successive sampling scheme, that is not only cost‐effective but also efficient as compared with the simple random sampling scheme. A number of Shewhart‐type control charts are proposed based on the said sampling scheme, and average run length is used as a performance indicator. Based on the average run length values, all the proposed charts are compared with existing Shewhart control chart for both positive and negative shifts in the process. Finally, the new proposals are applied to a real dataset where the variable of interest is an inner diameter of automobile engine piston rings made of steel. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
86.
Umair Shabbir Momna Rubab Akanksha Tyagi Deog-Hwan Oh 《International journal of molecular sciences》2021,22(1)
Curcumin is a polyphenolic natural compound with diverse and attractive biological properties, which may prevent or ameliorate pathological processes underlying age-related cognitive decline, Alzheimer’s disease (AD), dementia, or mode disorders. AD is a chronic neurodegenerative disorder that is known as one of the rapidly growing diseases, especially in the elderly population. Moreover, being the eminent cause of dementia, posing problems for families, societies as well a severe burden on the economy. There are no effective drugs to cure AD. Although curcumin and its derivatives have shown properties that can be considered useful in inhibiting the hallmarks of AD, however, they have low bioavailability. Furthermore, to combat diagnostic and therapeutic limitations, various nanoformulations have also been recognized as theranostic agents that can also enhance the pharmacokinetic properties of curcumin and other bioactive compounds. Nanocarriers have shown beneficial properties to deliver curcumin and other nutritional compounds against the blood-brain barrier to efficiently distribute them in the brain. This review spotlights the role and effectiveness of curcumin and its derivatives in AD. Besides, the gut metabolism of curcumin and the effects of nanoparticles and their possible activity as diagnostic and therapeutic agents in AD also discussed. 相似文献
87.
Che-Wei Lin Shabbir Syed Abdul Daniel L. Clinciu Jeremiah Scholl Xiangdong Jin Haifei Lu Steve S. Chen Usman Iqbal Maxwell J. Heineck Yu-Chuan Li 《Computer methods and programs in biomedicine》2014
Background
China's healthcare system often struggles to meet the needs of its 900 million people living in rural areas due to major challenges in preventive medicine and management of chronic diseases. Here we address some of these challenges by equipping village doctors (ViDs) with Health Information Technology and developing an electronic health record (EHR) system which collects individual patient information electronically to aid with implementation of chronic disease management programs.Methods
An EHR system based on a cloud-computing architecture was developed and deployed in Xilingol county of Inner Mongolia using various computing resources (hardware and software) to deliver services over the health network using Internet when available. The system supports the work at all levels of the healthcare system, including the work of ViDs in rural areas. An analysis done on 291,087 EHRs created from November 2008 to June 2011 evaluated the impact the EHR system has on preventive medicine and chronic disease management programs in rural China.Results
From 2008 to 2011 health records were created for 291,087 (26.25%) from 1,108,951 total Xilingol residents with 10,240 cases of hypertension and 1152 cases of diabetes diagnosed and registered. Furthermore, 2945 hypertensive and 305 diabetic patients enrolled in follow-up. Implementing the EHR system revealed a high rate of cholecystectomies leading to investigations and findings of drinking water contaminated with metals. Measures were taken to inform the population and clean drinking water was supplied.Conclusions
The cloud-based EHR approach improved the care provision for ViDs in rural China and increased the efficiency of the healthcare system to monitor the health status of the population and to manage preventive care efforts. It also helped discover contaminated water in one of the project areas revealing further benefits if the system is expanded and improved. 相似文献88.
Zain Shabbir Anas Razzaq Ghumman Shabbir Majeed Chaudhry 《Circuits, Systems, and Signal Processing》2016,35(9):3113-3134
A low-power, high-speed \(4\times 4\) multiplier using Dadda algorithm is proposed. The full adder blocks used in this multiplier have been designed using reduced-split precharge-data driven dynamic sum logic. Flip flops used in the pipeline registers have been designed to increase input signal noise margin, resulting in the minimization of output signal glitches. The multiplier circuit is implemented in 1P-9M Low-K UMC 90nm CMOS process technology. Post-layout simulations are carried out using Cadence Virtuoso. The proposed multiplier operates at a clock frequency of 3.5 GHz, with an average dynamic power consumption of 1.096 mW at a temperature of \(27\,^{\circ }\hbox {C}\) and 1 V supply voltage and occupies a chip area of \(76\,\upmu \hbox {m}\times 102\,\upmu \hbox {m}\). 相似文献
89.
Muhammad Bilal Khan Ali Hussain Kazim Muhammad Farooq Khalid Javed Aqsa Shabbir Rehan Zahid Sadaf Fatima Muhammad Rohail Danish Qasim Ali Ijaz Ahmad Chaudhry A.E. Atabani 《International Journal of Hydrogen Energy》2021,46(37):19633-19644
Biodiesel and oxyhydrogen (HHO) gas have shown promising results in improving engine performance and emissions. In this work, the effects of HHO gas and 5% biodiesel blends (B5) and their combined use in a 315 cc diesel engine have been analyzed. Biodiesel is produced by base catalyzed transesterification and cleaned by emulsification. Its calculated cetane index (CCI) was 61.4. HHO gas is produced from electrolysis of concentrated potassium hydroxide solution. The use of 5% biodiesel blend resulted in a significant rise of 9.4% in the brake thermal efficiency (BTE) and a maximum reduction of 8.19% in the brake specific fuel consumption (BSFC). HHO enrichment of diesel and biodiesel at 2.81 L/min through the intake manifold improved the torque and power by an average of over 3%. HHO addition also improved the BTE of diesel by a maximum of 3.67%. The combination of high CCI biodiesel fuel and HHO creates a mixture that has shortened the ignition delay (ID) to the point that adverse effects were observed due to the premature combustion as shown by the average decrease in the BTE of 2.97% compared to B5. Thus, B5, on its own, is found to be the optimum fuel under these conditions. 相似文献
90.
Muhammad Riaz Muhammad Abid Aroosa Shabbir Hafiz Zafar Nazir Zameer Abbas Saddam Akber Abbasi 《Quality and Reliability Engineering International》2021,37(4):1544-1560
In practical situations, the underlying process distribution sometimes deviates from normality and their distribution is partially or completely unknown. In that instance, rather than staying with/depending on the conventional parametric control charts, we consider non-parametric control charts due to their exceptional performance. In this paper, a new non-parametric double homogeneously weighted moving average sign control chart is proposed with the least assumptions. This chart is based on a sign test statistic for catching the smaller deviations in the process location. Run-length (RL) properties of the proposed chart are studied with the help of Monte Carlo simulations. Both in-control and out-of-control RL properties show that the proposed chart is a better contender as compared to some existing charts from the literature. A real-life application for practical consideration of the proposed chart is also provided. 相似文献