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41.
Energy efficiency analysis of air cycle heat pump dryers 总被引:2,自引:0,他引:2
In this paper, the feasibility of an air heat pump (reversed Brayton) cycle for tumbler clothes dryers is investigated. The goal is to increase the energy efficiency as compared to conventional electrically heated driers. Relatively simple models were used to compare the energy efficiency of the heat pump drier with that of a conventional air vented drier. The components were modeled using overall performance indices and thermodynamic relations. An air cycle heat pump dryer with practical components was found to be capable of significant efficiency improvements as compared with conventional dryers. 相似文献
42.
JuergenMueller 《纺织导报》2003,(6):104-106
全球范围内的纺纱厂一直面对着以下挑战和要求: ·为了保持竞争力,必须一直有稳定的纱线质量; ·国际性的竞争要求生产成本不断降低; 相似文献
43.
44.
Guntram Pausch Claus-Michael HerbachYong Kong Ralf LenteringCristina Plettner Katja RoemerFalko Scherwinski Juergen SteinPaul Schotanus Thomas Wilpert 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):374-380
The neutron capture detector (NCD) is introduced as a novel detection scheme for thermal and epithermal neutrons that could provide large-area neutron counters by using common detector materials and proven technologies. The NCD is based on the fact that neutron captures are usually followed by prompt gamma cascades, where the sum energy of the gammas equals to the total excitation energy of typically 6-9 MeV. This large sum energy is measured in a calorimetric approach and taken as the signature of a neutron capture event. An NCD consists of a neutron converter, comprising of constituents with large elemental neutron capture cross-section like cadmium or gadolinium, which is embedded in common scintillator material. The scintillator must be large and dense enough to absorb with reasonable probability a portion of the sum energy that exceeds the energy of gammas emitted by common (natural, medical, industrial) radiation sources. An energy window, advantageously complemented with a multiplicity filter, then discriminates neutron capture signals against background. The paper presents experimental results obtained at the cold-neutron beam of the BER II research reactor, Helmholtz-Zentrum Berlin, and at other neutron sources with a prototype NCD, consisting of four BGO crystals with embedded cadmium sheets, and with a benchmark configuration consisting of two separate NaI(Tl) detectors. The detector responses are in excellent agreement with predictions of a simulation model developed for optimizing NCD configurations. NCDs could be deployed as neutron detectors in radiation portal monitors (RPMs). Advanced modular scintillation detector systems could even combine neutron and gamma sensitivity with excellent background suppression at minimum overall expense. 相似文献
45.
We present a methodology for the calculation of highly accurate point clouds from an image stack obtained with a two-dimensional industrial X-ray computed tomography scanner. The basic idea is to apply a different threshold value to each computed tomography image, which is then used for the calculation of the point cloud. A dense and smooth cloud can be obtained by interpolating the grey values between pixles. Our method combines both. An easy to implement thresholding algorithm is used for the estimation of a slice-by-slice threshold and an interpolating algorithm to reconstruct highly accurate point clouds.It is shown that the point clouds approximate the true dimensions of a scanned part with sub-pixel accuracy. 相似文献
46.
Kurt Rentel Juergen Kuebnel 《电子产品世界》2005,(14):79-83
每当我们设计高速的混合信号系统时,我们最好先审视信号路径的每一环节,详细评估各区块的信号失真程度.本文主要介绍输入或接收器路径的设计.发送器或输出路径的设计将会留待以后再详细介绍.典型的接收器或仪表测量系统由信号传感器、模拟信号处理区块、数据转换器、接口及数字处理区块等多个不同环节组成(参看图1).但本文只集中讨论输入路径设计的模拟及混合信号部分.我们必须小心挑选信号路径的各个区块,才可取得预期的成效. 相似文献
47.
D Poenaru N Roblin M Bird S Duce A Groll D Pietak K Spry J Thompson 《Canadian Metallurgical Quarterly》1997,32(6):843-848
The multifactorial nature of functional constipation in children suggests that a multidisciplinary management approach may be effective. The authors tested this hypothesis in a newly created pediatric Bowel Management Clinic (BMC). Detailed data were collected prospectively on all patients seen in the clinic over the first 16 months. Both quantitative and qualitative analyses were performed to describe the index population and to demonstrate the impact of the intervention. Satisfaction with care in the clinic was measured using the Measure of Processes of Care tool, then compared with a normative sample. One hundred fourteen patients, all previously treated unsuccessfully for constipation, were referred to a team comprised of a physician, nurse practitioner, nurse educator, dietitian, and psychosocial nurse specialist. The mean age was 5.4 years with equal gender distribution. Between the first and last visits recorded, several variables including stool consistency and frequency, soiling frequency, abdominal pain, rectal pain, and rectal bleeding all showed statistically significant (P < .05) improvement. Qualitative data analysis showed the significant psychosocial impact of constipation on patients and their families. In the Measures of Processes of Care questionnaire, scores for the BMC were higher than normal on all scales except in provision of information. A multidisciplinary approach to functional constipation leads to both patient and parent satisfaction and significant short-term improvement. Further studies will examine the long-term impact of the clinic. 相似文献
48.
BG Feagan JW McDonald J Rochon A Laupacis RN Fedorak D Kinnear F Saibil A Groll A Archambault R Gillies 《Canadian Metallurgical Quarterly》1994,330(26):1846-1851
BACKGROUND: Long-term corticosteroid therapy for Crohn's disease is associated with important types of morbidity, such as osteoporosis. Safe and effective alternative treatments are required. Although a short-term benefit of cyclosporine in active Crohn's disease has been suggested, the long-term safety and efficacy of this treatment have not been established. METHODS: We conducted a randomized, double-blind, placebo-controlled evaluation of the effect of 18 months of low-dose cyclosporine treatment on the course of Crohn's disease. Adult patients whose disease had been active within the previous two years were randomly assigned to receive cyclosporine (151 patients) or placebo (154 patients) in addition to their usual therapy. Randomization was stratified according to center and score on the Crohn's Disease Activity Index (193 patients had scores of 150 or less, and 112 had scores greater than 150). The primary outcome measure was clinically important worsening of Crohn's disease, defined as a 100-point increase in the Crohn's Disease Activity Index from the patient's base-line value. Secondary outcomes were the use of prednisone and 5-amino-salicylates, mean score on the Crohn's Disease Activity Index and mean quality-of-life score, and the need for surgery. RESULTS: The condition of more patients worsened with cyclosporine than with placebo (91 of 151, or 60.3 percent, vs. 80 of 154, or 51.9 percent; P = 0.10). The median time to worsening of disease in patients receiving cyclosporine was 338 days, as compared with 492 days in patients receiving placebo (P = 0.25; relative risk, 1.22; 95 percent confidence interval, 0.86 to 1.72). Analyses of the mean Crohn's Disease Activity Index and quality-of-life scores and of the use of prednisone and 5-aminosalicylates also failed to demonstrate benefit. CONCLUSIONS: In our patient population, the addition of low-dose cyclosporine to conventional treatment for Crohn's disease did not improve symptoms or reduce requirements for other forms of therapy. 相似文献
49.
F. Kiermeier und D. Groll 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1970,142(2):120-123
Zusammenfassung Nach einer Diskussion der Prinzipien bisher vorgeschlagener Methoden für die Erfassung des Aflatoxins wurde eine darauf aufbauende quantitative Arbeitsweise für Käse entwickelt. Bei ihr wird der Käse mit Chloroform unmittelbar in der Soxhlet-Apparatur extrahiert; das Aflatoxnn auf einer Kieselgel-Dünnschichtplatte zweidimensional isoliert [Fließmittel Diäthyläther; Chloroform/Aceton (3 + 1)]. Nach Markierung im UV Wird das Aflatoxin mechanisch von der Platte isoliert, in Methanol gelöst und im Spektrometer bei 363 nm die Extinktion gemessen.
Determination of Aflatoxin B1 in Cheese
Summary Based on the principles of methods so far known, a quantitative method for determination of aflatoxin in cheese was developed. Cheese is directly extracted by chloroform in the Soxhlet apparatus; aflatoxin is isolated 2-dimensionally on a silicagel-thinlayer-plate (solvent diethylether; chloroform/aceton (3 + 1). After tracing the aflatoxin under the UV lamp, it is mechanically isolated, solved in methanol and the absorbante is measured spectrometrically at 363 nm.相似文献
50.