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排序方式: 共有484条查询结果,搜索用时 15 毫秒
51.
H Matsuda T Kusakabe Y Hayashida M Furukawa T Kawakami T Takenaka M Tsukuda 《Canadian Metallurgical Quarterly》1998,45(6):563-569
Changes made in 1997 and 1998 in the U.S. childhood immunization schedule are discussed, with a focus on the use of poliovirus, pertussis, and combination vaccines. Oral poliovirus vaccine (OPV), the vaccine of choice for all four doses in the polio immunization series since 1962, can cause vaccine-associated paralytic poliomyelitis (VAPP). The inactivated poliovirus vaccine (IPV) has not been associated with VAPP but must be administered by injection and provides inferior intestinal immunity. With the reduced threat of poliovirus importation into the United States, the risk of VAPP, although low, has become less acceptable. The Centers for Disease Control and Prevention accordingly recommended a shift from OPV to IPV in the childhood immunization schedule for the United States, effective January 1997. A sequential OPV and IPV series is recommended, but the schedule includes an OPV-only option, which may be preferred in order to avoid the required injections, and an IPV-only option, which is recommended for immunocompromised persons and their contacts. Concern over local and systemic reactions associated with whole-cell pertussis vaccines, in addition to controversy over a possible relationship between the whole-cell vaccine and neurologic damage, has led to the development of new diphtheria and tetanus toxoids and acellular pertussis vaccine products for use in the diphtheria and tetanus toxoids and pertussis immunization series. Several combination products were licensed in 1997, and more are on the way. This will mean fewer inoculations for children. Increased use of IPV and acellular pertussis products could reduce the frequency of VAPP due to OPV and the local and systemic reactions associated with whole-cell pertussis vaccine. 相似文献
52.
Super-hydrophobic surface has been prepared onto biodegradable polymer by a combination of transcribing microscopic structure of a water-repellent leaf and a chemical treatment. An aroid leaf has been chosen for the preparation of the super-hydrophobic surface since the leaf has concavity microscopic structure, which is easy to handle for a material use. The microscopic pattern was transcribed onto poly(ε-caprolactone) (PCL) sheet by using replica method, then it was further treated by soaking in a mixture of acetone/methanol solution. The resultant PCL having the microscopic concavity pattern showed high water contact angle of 148° and also showed antibacterial property for filamentous fungi. 相似文献
53.
Realization of all-optical flip-flop using directionally coupled bistable laser diode 总被引:1,自引:0,他引:1
M. Takenaka Y. Nakano 《Photonics Technology Letters, IEEE》2004,16(1):45-47
A novel all-optical flip-flop device has been realized using a directionally-coupled bistable laser diode (DC-BLD). We have fabricated the DC-BLD by a conventional fabrication technique of LDs. To separate the adjacent electrodes of the directional coupler, an oblique electron-beam evaporation technique was developed. By this self-align process, the two adjacent waveguides of the directional coupler were electrically isolated without employing any additional lithography step. Using the fabricated DC-BLD, all-optical flip-flop has been demonstrated due to the nonlinear effects of the saturable absorber and the directional coupler. The flip-flop operation has been achieved with sufficiently small input optical power level around 0 dBm. 相似文献
54.
Yusuke Suzuki Chisato Takenaka Rie Tomioka Hiromi Tsubota Yuka Takasaki Tomonari Umemura 《Mine Water and the Environment》2016,35(3):265-272
Bryophytes with high As accumulation affinity were identified in the aquatic environment. We surveyed a stream near copper mine tailings and then conducted laboratory experiments to confirm As accumulation in the bryophytes with high As affinity. We found that a moss, Scopelophila cataractae, accumulates As in addition to Cu in aquatic environments and confirmed it in laboratory experiments. The highest value for As in S. cataractae from the field survey was 1300 mg/kg dry weight at relatively low As concentrations in the stream water (0.005 mg/L). In addition, Brachythecium plumosum and Rhynchostegium riparioides may also be useful bryophytes for accumulation of Cu and As, though the mechanisms of As accumulation might differ between these two bryophytes and S. cataractae. 相似文献
55.
Hibi Y Asai K Arafuka H Hamajima M Iwama T Kawai K 《Journal of Bioscience and Bioengineering》2011,111(5):547-549
La(3+) and not Ca(2+) increases methanol dehydrogenase (MDH) activity in Methylobacterium radiotolerans NBRC15690. La(3+)- and Ca(2+)-MDH-like proteins were found to be homodimeric (α(2)) and heterotetrameric (α(2)β(2)), respectively. N-terminal amino acid sequences of these proteins revealed that La(3+)- and Ca(2+)-MDH-like proteins were encoded by xoxF and mxaFI, respectively. 相似文献
56.
Abstract: We examined the acid resistance and verocytotoxin (VT) productivity of enterohemorrhagic Escherichia coli O157:H7 irradiated by microwave with a domestic microwave oven and a commercial microwave radiator equipped with a thermo‐regulator. When the cell suspension (5 mL) chilled at 0 °C was treated with a domestic microwave oven at weak power (2.45 GHz, 100 W) for 60 s, the living cell number was reduced by 2 orders (final temperature, about 65 °C). The surviving cells showed lower acid resistance and VT productivity than nonirradiated cells. To examine the nonthermal effect of microwave on acid resistance and VT productivity, the cells in Luria‐Bertani medium were intermittently irradiated to keep the culture temperature at 37 °C with the microwave radiator (2.45 GHz, 0.6 W/mL). The intermittent radiation slightly reduced the acid resistance, but clearly suppressed the VT productivity. Microwave oven is probably useful for reducing not only the living cell number but also the acid resistance and VT productivity of EHEC O157:H7. 相似文献
57.
Shuji Furui Hisashi Umekawa Kouichi Hayashi Mamoru Ozawa Nobuyuki Takenaka 《亚洲传热研究》2003,32(8):727-739
Fluidized bed combustion is one of the advantageous technologies for coal and/or incineration firing especially with respect to the environmental protection of emissions, such as NOx/SOx. Bed material movement in such a fluidized bed has a prime importance in the heat transfer process. Thus, quantitative measurement of the bed material movement and the void fraction are indispensable for better understanding of the fluidized bed. In this investigation, neutron radiography is applied to visualize the bed material movement in a simulated fluidized bed heat exchanger installed with vertical tubes. Bubble behavior and void fraction profile are obtained by the image processing technique. Bubble movement is highly restrained by these vertical tubes, so that the bubbles rise up along the tube. The bubble diameter is well correlated by the modified Mori and Wen's correlation taking into account the pitch of the tube arrangement. The bubble rise velocity and void fraction are well correlated by applying the drift‐flux model. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(8): 727–739, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10127 相似文献
58.
Noriyuki Miyata Hiroyuki IshiiYuji Urabe Taro ItataniTetsuji Yasuda Hisashi YamadaNoboru Fukuhara Masahiko HataMomoko Deura Masakazu SugiyamaMitsuru Takenaka Shinichi Takagi 《Microelectronic Engineering》2011,88(12):3459-3461
Electrical and physical characteristics of the Al2O3/InGaAs interfaces with (1 1 1)A and (1 0 0) orientations were investigated in an attempt to understand the origin of electron mobility enhancement in the (1 1 1)A-channel metal-insulator-semiconductor field-effect-transistor. The (1 1 1)A interface has less As atoms of high oxidation states as probed by X-ray photoelectron spectroscopy. The electrical measurements showed that energy distribution of the interface traps for the (1 1 1)A interface is shifted toward the conduction band as compared to that for the (1 0 0) interface. Laterally-compressed cross-section transmission electron microscopy images showed that the characteristic lengths of the interface roughness are different between the (1 1 1)A and (1 0 0) interfaces. The contributions of the Coulomb and roughness scattering mechanisms are discussed based on the experimental results. 相似文献
59.
Effects of photoirradiation in UV and VUV regions during plasma exposure to polymers 总被引:1,自引:0,他引:1
Ken Cho Yuichi Setsuhara Kosuke Takenaka Masaharu Shiratani Makoto Sekine Masaru Hori 《Thin solid films》2011,519(20):6810-6814
Interactions between photons irradiated from Ar-O2 mixture plasmas and polymer surfaces were investigated on the basis of depth analyses of chemical bonding states in the nano-surface layer of polyethylene terephthalate (PET) films via hard X-ray photoelectron spectroscopy (HXPES) and conventional X-ray photoelectron spectroscopy (XPS). The PET films were exposed to photons from the Ar-O2 mixture plasmas by covering the PET samples with MgF2 and quartz windows as optical filters for evaluation of photoirradiation effects in ultraviolet (UV) and vacuum ultraviolet (VUV) regions. The HXPES results indicated that the degradation of the chemical bonding states due to photoirradiation in regions was insignificant in deeper regions up to about 50 nm from the surface. Whereas, conventional XPS analysis showed that CO bond, OCO bond and CO bond increased after photoirradiation in UV and VUV regions. These results suggest that the increase in oxygen functionalities (CO bond, OCO bond and CO bond) may be attributed to chemical reactions and/or terminations of scissed bonds via photodecompositions of the polymer with oxygen and/or OH species (oxygen molecules and radicals during plasma exposure and/or oxygen molecules and moisture after taking the PET samples out of the plasma reactor to the ambient air) in the vicinity of the sample surface. 相似文献
60.
BACKGROUND: Venodilation is thought to be one of the mechanisms underlying propofol-induced hypotension. The purpose of this study is to test two hypotheses: (1) propofol increases systemic vascular capacitance, and (2) the capacitance change produced by propofol is a result of an inhibition of sympathetic vasoconstrictor activity. METHODS: In 33 Wistar rats previously anesthetized with urethane and ketamine, vascular capacitance was examined before and after propofol infusion by measuring mean circulatory filling pressure (Pmcf). The Pmcf was measured during a brief period of circulatory arrest produced by inflating an indwelling balloon in the right atrium. Rats were assigned into four groups: an intact group, a sympathetic nervous system (SNS)-block group produced by hexamethonium infusion, a SNS-block + noradrenaline (NA) group, and a hypovolemic group. The Pmcf was measured at a control state and 2 min after a bolus administration of 2, 10, and 20 mg/kg of propofol. RESULTS: The mean arterial pressure (MAP) was decreased by propofol dose-dependently in intact, hypovolemic, and SNS-block groups, but the decrease in MAP was less in the SNS-block group (-25%) than in the intact (-50%) and hypovolemic (-61%) groups. In the SNS-block + NA group, MAP decreased only at 20 mg/kg of propofol (-18%). The Pmcf decreased in intact and hypovolemic groups in a dose-dependent fashion but was unchanged in the SNS-block and SNS-block + NA groups. CONCLUSIONS: The results have provided two principal findings: (1) propofol decreases Pmcf dose-dependently, and (2) the decrease in Pmcf by propofol is elicited only when the sympathetic nervous system is intact, suggesting that propofol increases systemic vascular capacitance as a result of an inhibition of sympathetic nervous system. 相似文献