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1.
Transportable equipment for on-site thermal nondestructive testing is described. The equipment is constructed from two separate units: a hand-held infrared line scanner and a remote unit containing all the necessary control devices. The sample surface is heated by manually scanning a line source over the surface and the resulting surface temperature rise is simultaneously measured with the line scanner. The heating line is generated either by a line-focused laser beam or by a radio frequency induction coil. The obtained surface temperature distribution of the monitored area is presented as a pseudo-color image. The feasibility of the method is demonstrated with a carbon-glass fiber composite sample.  相似文献   
2.
A new method was developed which enabled us to obtain high-resolution images of the distribution of an oil-borne stain in a saw-textured plywood surface. The method involved treating 90 μm thick plywood sections, which had been cut transversely through the wood-coating interface using a sliding microtome, with osmium tetroxide (OsO4) prior to examination with a field-emission scanning electron microscope (FE-SEM) operating in backscattered electron imaging (BEI) mode. The combination of OsO4 staining and use of FE-SEM-BEI afforded excellent contrast differentiation between the coating and wood cell walls, revealing coating penetration into even nano-size cell wall cracks and delaminations formed during band-sawing of the plywood. The novel technique described adds a new dimension to probing wood–coating interface.  相似文献   
3.
In this study, we explored how stereoscopic depth affects performance and user experience in a mobile device with an autostereoscopic touch display. Participants conducted a visual search task with an image gallery application on three layouts with different depth ranges. The task completion times were recorded, and the participants were asked to rate their experiences. The results revealed that the image search times were facilitated by a mild depth effect and that too great a depth slowed search times and decreased user-experience ratings.  相似文献   
4.
随着网络技术的发展,Internet已成为最具市场潜力的技术领域,使用Web技术设计的数据库应用软件,是目前Inter-net市场的技术中坚。在设计与实现"网络图书销售管理系统"的过程中,综合使用了HTML、Access、ODBC等多种网络编程技术。并大量使用ASP的内置数据库组件,通过ODBC数据源和ADO组件对象技术访问、更新和修改数据库的表中的内容。  相似文献   
5.
The pH dependence of iron(II)/iron(III) product distribution, following reduction of the hypervalent iron in equine ferrylmyoglobin by the protein moiety of the pigment (so-called autoreduction) and by NADH (nicotinamide adenine dinucleotide, reduced) and the rate of reduction was found to depend different on pH. Autoreduction is specific acid catalysed and has a more modest temperature dependence than autoxidation of oxymyoglobin, with the activation parameters H #=58.5±0.4 kJ·mol–1 and S #=2.7±0.1 J·mol–1·K–1 in 0.16 mol·1–1 NaCl. The product of autoreduction is the iron(III) pigment metmyoglobin, which is slightly modified in the protein moiety. The reaction has a positive kinetic salt effect from which it is deduced that the reactive centre of ferrylmyoglobin has a charge of +1 in agreement with the structure Fe(IV)=O. Reduction by NADH involves parallel reactions of two pigment forms in acid/base equilibrium with each other with a pK a equal to 4.9, both forms yielding metmyoglobin as well as the iron(II) pigment, oxymyoglobin, as products. The protonated form reacts faster than the deprotonated form, and two-electron transfer has greater importance for the protonated form with a limiting Fe(II)/Fe(III) product ratio of 0.6 in acidic solution compared to 0.12 in alkaline solution. A square root dependence of rate on NADH concentration suggests involvement of NAD·radicals with a disproportionation as the termination reaction.
Säure-katalysierte Reduktion von Ferrylmyoglobin. Produktdistribution und Kinetik der Autoreduktion und Reduktion von NADH
Zusammenfassung Die Reaktionsgeschwindigkeit und das Eisen(II)/Eisen(III)-Verhältnis des Produkts nach Reduktion von hypervalentem Eisen in Ferrylmyoglobin aus Pferden zeigt eine unterschiedliche pH-Abhängigkeit der sogenannten Autoreduktion (Reduktion am Proteinteil des Pigments) sowie der Reduktion durch NADH. Die Autoreduktion weist eine spezifische Säure-Katalyse auf sowie eine moderate Temperaturabhängigkeit im Vergleich zur Autooxidation von Oxymyoglobin mit den Aktivierungsparametern H #=58.5±0.4 kJ·mol–1 und S #=2.7±0.1 J·mol–1·K–1 in 0.16 mol·1–1 NaCl. Das Produkt der Autoreduktion ist das Eisen(III)-Pigment Metmyoglobin mit leicht modifiziertem Proteinanteil. Die Reaktion hat einen positiv kinetischen Salzeffekt, woraus zu erschließen ist, daß das reaktive Zentrum im Ferrylmyoglobin die Ladung +1 übereinstimmend mit der Struktur Fe(IV)=O besitzt. Die Reduktion durch NADH weist auf parallele Reaktionen von zwei Pigmentformen in einem Säure/Base-Gleichgewicht mit pk a=4.9 hin, beide Formen ergeben Metmyoglobin sowie das Eisen(II)-Pigment Oxymyoglobin als Produkt. Die protonisierte Form reagiert schneller als die deprotonisierte Form, und eine zwei-Elektronenübertragung hat größere Bedeutung für die protonisierte Form mit einem Fe(II)/Fe(III) Produktverbrauch von 0.6 in der Säurelösung und 0.12 in der Baselösung. Die Quadratwurzel Abhängigkeit der Geschwindigkeit von NADH deutet auf eine Teilnahme von NAD-Radikalen mit Disproportionierung als Schlußreaktion.
  相似文献   
6.
During the production and recycling of asphalt concrete, bitumen in contact with inorganic particles is exposed to air at high temperatures. As a result an oxidation of bitumen, also known as aging, occurs. The reaction between bitumen and air at 163 °C was studied insitu with and without the presence of inorganic impurities by means of fourier transform infrared spectroscopy in the attenuated reflectance mode. This oxidation was discovered to be a step-wise reaction facilitated by the oxidation of thiols and creation of peroxides within the system. The rate of reaction was demonstrated to depend on the type of impurity present, of which iron (III) chloride was the strongest catalyst. It was further demonstrated that the oxidation reaction is inhibited by the adsorption of thiol species present in the system on copper particles. Combining copper with the iron (III) chloride-containing system also resulted in the inhibition of signal increase in the sulfoxide region of the spectra. The results of this preliminary research on the bitumen oxidation reaction presented are proposed for further research regarding control of aging of asphalt concrete, especially during the recycling works.  相似文献   
7.
Lung cancer is one of the deadliest diseases in the world. Non‐small cell lung cancer (NSCLC) is the most common and dangerous type of lung cancer. Despite the fact that NSCLC is preventable and curable for some cases if diagnosed at early stages, the vast majority of patients are diagnosed very late. Furthermore, NSCLC usually recurs sometime after treatment. Therefore, it is of paramount importance to predict NSCLC recurrence, so that specific and suitable treatments can be sought. Nonetheless, conventional methods of predicting cancer recurrence rely solely on histopathology data and predictions are not reliable in many cases. The microarray gene expression (GE) technology provides a promising and reliable way to predict NSCLC recurrence by analysing the GE of sample cells. This study proposes a new model from GE programming to use microarray datasets for NSCLC recurrence prediction. To this end, the authors also propose a hybrid method to rank and select relevant prognostic genes that are related to NSCLC recurrence prediction. The proposed model was evaluated on real NSCLC microarray datasets and compared with other representational models. The results demonstrated the effectiveness of the proposed model.Inspec keywords: lung, cancer, lab‐on‐a‐chip, genetics, patient diagnosisOther keywords: NSCLC recurrence prediction, microarray data, GE programming, nonsmall cell lung cancer, cancer recurrence, histopathology data, microarray gene expression, prognostic genes  相似文献   
8.
指纹图像质量分析   总被引:8,自引:0,他引:8  
提出一种将局部分析和全局分析相结合,综合评价图像质量的方法.首先将指纹图像划分成32×32的子块,对每一块做快速傅里叶变换(fastFouriertransform,FFT),计算块频谱分布图的最小转动惯量和偏心率,从这些参数得到块质量的局部分析结果;然后考察每块图像的频域特征参数(方向、频率等)与其8邻域块相应参数的关系,从纹线流势的全局观点聚类形成图像的清晰区和模糊区;最后综合局部分析和全局分析的结果,给出指纹图像的质量评价.实验结果表明这是一种合理的、有效的方法.  相似文献   
9.
对C/S和B/S结构体系进行了分析比较,然后提出了一种新的基于C/S和B/S的混合系统结构的管理信息系统运行模式。  相似文献   
10.
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