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91.
92.
M Shindoh I Chiba M Yasuda T Saito K Funaoka T Kohgo A Amemiya Y Sawada K Fujinaga 《Canadian Metallurgical Quarterly》1995,76(9):1513-1521
BACKGROUND: The etiology of oral squamous cell carcinoma (SCC) is still obscure. Since human papillomavirus (HPV) DNAs are associated with carcinoma of the uterine cervix, carcinomas of the oral cavity were investigated to ascertain if these viruses are present in squamous carcinomas of this anatomic site. METHODS: Seventy-seven oral mucosal SCCs were examined for the presence of HPV DNAs by polymerase chain reaction and dot blot hybridization. Immunohistochemical detection of proliferating cell nuclear antigen (PCNA) and p53 was performed and single strand conformation polymorphism analysis for p53 was undertaken. In situ hybridization detection of HPV-16 DNA also was performed. RESULTS: Human papillomavirus-16 DNA was detected in 23 cases of oral SCC and both HPV-16 and HPV-18 DNA were detected in one case of tongue SCC. Human papillomavirus DNAs were detected of 11 of 33 tongue, 4 of 15 gingival, 2 of 4 palate, 2 of 5 buccal mucosa, 3 of 7 maxillary sinus, and 2 of 11 the floor of the mouth SCCs. None were detected in SCCs of the retromolar region (0/2). Immunohistochemical examination for p53 was performed in 26 cases of oral SCC and the accumulation of p53 protein was observed in 6 cases (i.e., in 4 of 17 HPV DNA-negative cases and in 2 of 9 HPV DNA-positive cases). Single strand conformation polymorphism analysis confirmed gene mutations in all 6 cases. Human papillomavirus-16 DNA was predominantly identified in cancer cells that showed a morphologic resemblance to basal cells and its hybridized signal in keratinized cells was reduced by in situ hybridization detection. Immunohistochemical detection of PCNA revealed its cooccurrence with HPV-16 DNA in cancer cells. CONCLUSIONS: These results suggest that HPV-16 DNA sequences may have the capability to maintain the proliferative state of epithelial cells, and may contribute to the production of malignant phenotypes. 相似文献
93.
Protein Folding in the Presence of Water‐Soluble Cyclic Diselenides with Novel Oxidoreductase and Isomerase Activities 下载免费PDF全文
Dr. Kenta Arai Haruhito Ueno Yuki Asano Gaurango Chakrabarty Shingo Shimodaira Prof. Dr. Govindasamy Mugesh Prof. Dr. Michio Iwaoka 《Chembiochem : a European journal of chemical biology》2018,19(3):207-211
The protein disulfide isomerase (PDI) family, found in the endoplasmic reticulum (ER) of the eukaryotic cell, catalyzes the formation and cleavage of disulfide bonds and thereby helps in protein folding. A decrease in PDI activity under ER stress conditions leads to protein misfolding, which is responsible for the progression of various human diseases, such as Alzheimer's, Parkinson's, diabetes mellitus, and atherosclerosis. Here we report that water‐soluble cyclic diselenides mimic the multifunctional activity of the PDI family by facilitating oxidative folding, disulfide formation/reduction, and repair of the scrambled disulfide bonds in misfolded proteins. 相似文献
94.
Hitoshi Iida Moto Kinoshita Kuniaki Amemiya 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(5):409-421
This paper presents a highly sensitive terahertz (THz) calorimeter developed using a magnetically loaded epoxy as a broadband absorber. The reflection loss of the absorber, which has a pyramidally textured surface, is less than 0.04, as determined using a THz time-domain spectrometer and a vector network analyzer. The THz calorimeter successfully enabled the measurement of the absolute THz power from a photomixer at microwatt levels at room temperature. The measurement uncertainties at a 95% confidence level were 6.2% for 13 μW at 300 GHz and 5.6% for 1.5 μW at 1 THz, respectively. Details of the evaluation and uncertainty analyses are also presented. 相似文献
95.
Dual-eyes Vision-based Docking System for Autonomous Underwater Vehicle: an Approach and Experiments
Myo Myint Kenta Yonemori Khin Nwe Lwin Akira Yanou Mamoru Minami 《Journal of Intelligent and Robotic Systems》2018,92(1):159-186
A critical challenge for autonomous underwater vehicles (AUVs) is the docking operation for applications such as sleeping under the mother ship, recharging batteries, transferring data, and new mission downloading. The final stage of docking at a unidirectional docking station requires the AUV to approach while keeping the pose (position and orientation) of the vehicle within an allowable range. The appropriate pose therefore demands a sensor unit and a control system that have high accuracy and robustness against disturbances existing in a real-world underwater environment. This paper presents a vision-based AUV docking system consisting of a 3D model-based matching method and Real-time Multi-step Genetic Algorithm (GA) for real-time estimation of the robot’s relative pose. Experiments using a remotely operated vehicle (ROV) with dual-eye cameras and a separate 3D marker were conducted in a small indoor pool. The experimental results confirmed that the proposed system is able to provide high homing accuracy and robustness against disturbances that influence not only the captured camera images but also the movement of the vehicle. A successful docking operation using stereo vision that is new and novel to the underwater vehicle environment was achieved and thus proved the effectiveness of the proposed system for AUV. 相似文献
96.
Yoshinobu Nozue Satomi Hirano Naohiko Kawasaki Atsuo Iida Yoshiyuki Amemiya 《Polymer》2004,45(25):8299-8302
In poly(ε caprolacton) (PCL)/poly(vinyl butyral) (PVB) blend which forms band spherulite, some straight lines along the radial direction of the spherulites are observed under polarized optical microscope (POM). By using microbeam scanning WAXS, we have investigated the handedness of lamella twisting on the left and right sides of the straight line. As a result, we have observed that the manner of periodic change of 110 reflection in WAXS is reversed between left and right sides of the straight line with respect to the direction of the X-ray beam scanning. This result clearly shows that the straight line observed under POM is the boundary line of handedness in band spherulite, and further, that both handednesses co-exist within one spherulite. It also implies that the lamellae growing from one nucleus are twisted cooperatively only with neighboring lamellae but not with all lamellae in the spherulite of PCL/PVB. 相似文献
97.
Hideo Sugahara Kenta Arai Naoki Kamata Masakazu Kato 《Electrical Engineering in Japan》2015,190(2):41-56
This paper proposes optimal total planning for incinerator plants (IPs) in a typical urban area, which includes a method of determining the number of plants and the capacities of the IPs. Burnable municipal refuse is disposed of sanitarily by high‐temperature incineration at the IPs. At the same time, power generation from waste (PGW) is being performed at many IPs to recover energy. At present, the amount of energy generated by PGW is greater than that of wind power or photovoltaic power generation. However, PGW has a limited generation efficiency and low generation output due to the smaller capacity of IPs. To overcome the above weakness, highly efficient PGW is necessary with total integration and scaling up of IPs. Regarding total integration and scaling up, operation in larger areas is favorable from the point of view of refuse volume and collection. In the planning stage, both the cost of IPs and refuse collection, which is important for refuse disposal, should be taken into account comprehensively. Optimal total planing for IPs can be performed in two stages. First, the disposal capacity Gk of an IP versus the number of plants K is decided by constraints. Gk is about the same for all K because of maintenance and refuse collection, and is greater than 300 tons per day in steps of 100 tons per day. Gk should be decided not only by refuse volume but also by cessation of operation at plants due to maintenance or faults. Second, the cost of each value of K is calculated based on the construction and operating costs of the IPs, income from selling the energy of PGW, and refuse collection costs. Therefore, the value of K with the minimum cost is selected as the optimal number of IPs. A numerical simulation of an area with a population of 3 million indicates that the optimal plant number is 4. At present there are eight or nine IPs in cities of 3 million people. The above cost reduction effect will be about 15% from the present value. Considering the situation of aging IPs, a decreasing trend in refuse volume, and the stringent financial conditions of local governments, the proposed method is very effective and realistic. 相似文献
98.
Composite film of carbon nanotube (CNT) and polytetrafluoroethylene (PTFE) was successfully formed by using their dispersion fluids. This CNT/PTFE composite film was electrically conductive in the range of 10 S cm−1. The proton exchange membrane fuel cell (PEMFC) was assembled with the stainless steel bipolar plate coated with the CNT/PTFE composite film. This coating decreased the contact resistance between the surface of the bipolar plate and the membrane electrode assemble (MEA). Therefore, the output power of the fuel cell increased by 1.6 times. 相似文献
99.
Nobuhiro Okada Jinjun Qiu Kenta Nakamura Eiji Kondo 《Artificial Life and Robotics》2009,14(2):114-117
This article proposes multiple self-organizing maps (SOMs) for control of a visuo-motor system that consists of a redundant
manipulator and multiple cameras in an unstructured environment. The maps control the manipulator so that it reaches its end-effector
at targets given in the camera images. The maps also make the manipulator take obstacle-free poses. Multiple cameras are introduced
to avoid occlusions, and multiple SOMs are introduced to deal with multiple camera images. Some simulation results are shown. 相似文献
100.
Kenta Aizawa Hiroki Takagi Eri Kokubo Masayasu Takada 《Journal of Applied Glycoscience》2021,68(3):53
Carbohydrate materials that produce lower postprandial blood glucose increase are required for diabetic patients. To develop slowly digestible carbohydrates, the effect of degree of polymerization (DP) of α-1,6 glucan on its digestibility was investigated in vitro and in vivo. We prepared four fractions of α-1,6 glucan composed primarily of DP 3–9, DP 10–30, DP 31–150, and DP 151+ by fractionating a dextran hydrolysate. An in vitro experiment using digestive enzymes showed that the glucose productions of DP 3–9, DP 10–30, DP 31–150, and DP 151+ were 70.3, 53.4, 28.2, and 19.2 % in 2 h, and 92.1, 83.9, 39.6, and 33.3 % in 24 h relative to dextrin, respectively. An in vivo glycemic response showed that the incremental area under the curve (iAUC) of blood glucose levels of α-1,6 glucan with DP 3–9, DP 10–30, DP 31–150, and DP 151+ were 99.5, 84.3, 65.4, and 40.1 % relative to dextrin, respectively. These results indicated that α-1,6 glucan with higher DP had stronger resistance to digestion and produced a smaller blood glucose response. DP 10–30 showed significantly lower maximum blood glucose levels than dextrin; however, no significant difference was observed in iAUC, indicating that DP 10–30 was slowly digestible. In addition, α-1,6 glucan was also produced using an enzymatic reaction with dextrin dextranase (DDase). This produced similar results to DP 10–30. The DDase product can be synthesized from dextrin at low cost. This glucan is expected to be useful as a slowly digestible carbohydrate source. 相似文献