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1.
Akiyoshi Wakatani 《Parallel Computing》2004,30(12):1345-1359
It is hard to implement the ADI method in an efficient way on distributed-memory parallel computers. We propose “P-scheme” which parallelizes a tridiagonal linear system of equations for the ADI method, but its effectiveness is limited to the cases where the problem size is large enough mainly because of the communication cost of the propagation phase of the scheme.
In order to overcome this difficulty, we propose an improved version of the P-scheme with “message vectorization” which aggregates several communication messages into one and alleviates the communication cost. Also we evaluate the effectiveness of message vectorization for the ADI method and show that the improved version of the P-scheme works well even for smaller problems and linear and super-linear speedups can be achieved for 8194 × 8194 and 16,386 × 16,386 problems, respectively. 相似文献
2.
氧浓度对近临界水中纤维素分解的影响 总被引:3,自引:0,他引:3
研究了不同初始氧浓度对纤维素在近临界水中分解的影响,实验结果表明,氧浓度显著地影响产物总碳收支平衡,液相不同组分的收率、气体的产量以及气相产物的组成,微量氧对产物总碳收支平衡影响不大,而对液相不同组分的收率有一定的影响。从实验结果可以看出,离子型反应机理在纤维素水解的第一步中起主导作用。而单糖的进一步分解是一个以自由基反应机理为主的过程。 相似文献
3.
Solving regularized least squares with qualitatively controlled adaptive cross‐approximated matrices
The adaptive cross‐approximation (ACA) technique is applied to accelerating an inverse‐problem solver that estimates charge distribution on a dielectric spacer. The ACA generates an approximated system‐matrix that enables us to carry out high‐speed inverse calculation. We designed an approximation procedure based on ACA with some additional concepts, that is, (a) partitioning of matrix based on algebraic information, (b) approximation quality control based on matrix norms, and so on. The tested solver (LSQR for regularized least squares) with ACA demonstrates about 10 times faster performance than that without ACA. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(3): 10–18, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20326 相似文献
4.
Hideaki Yamada Akiyoshi Chayahara Yoshiaki Mokuno Shin-ichi Shikata 《Diamond and Related Materials》2008,17(4-5):494-497
A new structure of microwave plasma for chemical vapor deposition of diamond crystal is proposed. The structure is designed numerically, for which an improved model given in our previous work [H. Yamada et al., J. Appl. Phys. 101 (2007), art. no. 063302.] is utilized. The experimental observations and numerical predictions agree well with each other. It is demonstrated experimentally that the proposed structure can achieve a growth rate larger than 50 μm/h over an area 1 in. in diameter. 相似文献
5.
Motility related protein 1 (MRP1/CD9) expression in colon cancer 总被引:1,自引:0,他引:1
M Mori K Mimori T Shiraishi M Haraguchi H Ueo GF Barnard T Akiyoshi 《Canadian Metallurgical Quarterly》1998,4(6):1507-1510
STUDY OBJECTIVES: To examine the incidence and clinical significance of prolonged air leak (PAL) in patients undergoing radical upper lobectomy and to determine potential risk factors for PAL in this group of patients. DESIGN: Retrospective review of a prospective database. SETTING: Experience of one thoracic surgeon at a tertiary care cancer center. PATIENTS: One hundred consecutive patients undergoing right upper lobectomy and mediastinal lymph node dissection for non-small cell lung cancer over an 11-year period. MEASUREMENTS: PAL was defined as an air leak lasting >7 days. Preoperative, intraoperative, and postoperative clinical data were collected and analyzed to determine the factors associated with PAL. RESULTS: PAL was the most prevalent postoperative complication, comprising 25.5% of all complications seen, and lasting an average of 12.1+/-5.3 days. In 21 of the 26 patients with PAL, this complication was the only morbidity identified. There was no statistically significant difference in patient age, gender, preoperative FEV1 and diffusion of carbon monoxide, exposure to neoadjuvant chemotherapy, status of pulmonary fissures, or pathologic stage between the PAL group vs the remaining 74 patients without this complication. A significantly greater proportion of patients with PAL had FEV1/FVC ratio < or =50% (6/26 vs 5/74; p=0.02). Patients with PAL had significantly longer median length of hospital stay (11 vs 7 days; p=0.0001). Moreover, PAL was the single most common reason for an extended length of hospitalization (21/58, 36% of all causes). CONCLUSION: PAL is an alarmingly common postoperative complication and is the most frequent cause of an extended length of hospital stay in patients undergoing radical upper lobectomy. Severe obstructive pulmonary disease predisposes patients to the development of this complication. 相似文献
6.
Masayuki Asada Yoshinari Miura Akiyoshi Osaka Katsutoshi Oukami Seishiro Nakamura 《Journal of Materials Science》1988,23(9):3202-3205
Calcium hydroxyapatite (Ca-HAP) ceramics containing tricalcium phosphate (TCP) were soaked in three solutions: phosphate buffer, tris buffer, and simulated body fluid (SBF). Petal-like crystals of Ca-HAP were deposited on the Ca-HAP ceramics when (i) Ca-HAP ceramics contained -TCP, (ii) the soaking solution contained phosphate ion and (iii) the pH of soaking solution was higher than 7.3. These conditions facilitate the presence of HPO
4
2–
and Ca2+ ions, the latter from dissolution of -TCP. A well-defined X-ray diffraction pattern for the deposited Ca-HAP crystals indicates preferred growth of {002} planes. Slower crystal growth of Ca-HAP was found for SBF (pH=7.5) than in the phosphate buffer, due possibly to the lower phosphate ion content in SBF. 相似文献
7.
Hideyuki Yoshimatsu Hitoshi Kawasaki Akiyoshi Osaka 《Journal of Materials Science》1988,23(1):332-336
Zr-Al organometallic compounds have been spray-dried and heated at temperatures 600 to 1400°C to prepare ZrO2-Al2O3 composite powders. The powders consist of balloon-like particles 0.5 to 2 m in diameter with homogeneously dispersed tetragonal ZrO2 grains 0.1 to 0.2 m in diameter. The tetragonal fraction of ZrO2 in the composite powders is higher than that in the powders prepared from sols of Zr(OBun)4 and Al[OCH(CH3)2]3. The fraction is affected by the organofunctional group in the Zr-Al compounds.Zr(OBun)4 = Zr(OC4Hgn)4; Al[OCH(CH3)2]3 = Al(OPri)3. 相似文献
8.
A thermodynamic property model with new mixing rules using the Helmholtz free energy is presented for the binary mixture of
methane and hydrogen sulfide based on experimental Pρ Tx data, vapor–liquid equilibrium data, and critical-point properties. The binary mixture of methane and hydrogen sulfide shows
vapor–liquid–liquid equilibria and a divergence of the critical curve. The model represents the existing experimental data
accurately and describes the complicated behavior of the phase equilibria and the critical curve. The uncertainty in density
calculations is estimated to be 2%. The uncertainty in vapor–liquid equilibrium calculations is 0.02 mole fraction in the
liquid phase and 0.03 mole fraction in the vapor phase. The model also represents the critical points with an uncertainty
of 2% in temperature and 3% in pressure. Graphical and statistical comparisons between experimental data and the available
thermodynamic models are discussed 相似文献
9.
Riku Kawasaki Kosuke Kondo Risako Miura Keita Yamana Hinata Isozaki Risako Shimada Shogo Kawamura Hidetoshi Hirano Tomoki Nishimura Naoki Tarutani Kiyofumi Katagiri Alexandra Stubelius Shin-ichi Sawada Yoshihiro Sasaki Kazunari Akiyoshi Atsushi Ikeda 《International journal of molecular sciences》2022,23(9)
Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy. 相似文献
10.
Optimal Digital Controller Design for a Servo Motor Taking Account of Intersample Behavior 下载免费PDF全文
A continuous‐time plant with a discretized continuous‐time controller does not yield stability if the sampling rate is lower than some certain level. Thus far, high‐performance electronic control has made use of expensive hardware needed to implement discretized continuous‐time controllers; low‐cost hardware generally does not have a sufficiently high sampling rate. This technical note presents results comparing performance indexes with and without intersample behavior, and provides some answers to the question of how a low‐specification device can control a plant effectively. We consider a machine simulating wafer handling robots, which is an electromechanical system driven by a direct drive motor, at a semiconductor factory. We illustrate the controller design for the robot with and without intersample behavior, and present simulations and experimental results using these controllers. Taking intersample behavior into account proves to be effective in improving control performance and makes it possible to choose a relatively long sampling period. Controller design in terms of the performance index with intersample behavior makes it possible to deal with situations in which a sufficiently short sampling period may not be employed, and freedom of controller design may be widened, especially regarding the choice of the sampling period. 相似文献