全文获取类型
收费全文 | 180篇 |
免费 | 11篇 |
专业分类
电工技术 | 2篇 |
综合类 | 1篇 |
化学工业 | 73篇 |
金属工艺 | 12篇 |
机械仪表 | 1篇 |
建筑科学 | 6篇 |
矿业工程 | 1篇 |
能源动力 | 3篇 |
轻工业 | 3篇 |
无线电 | 12篇 |
一般工业技术 | 31篇 |
冶金工业 | 7篇 |
原子能技术 | 2篇 |
自动化技术 | 37篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 11篇 |
2021年 | 20篇 |
2020年 | 3篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 12篇 |
2015年 | 8篇 |
2014年 | 14篇 |
2013年 | 11篇 |
2012年 | 13篇 |
2011年 | 22篇 |
2010年 | 10篇 |
2009年 | 9篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
排序方式: 共有191条查询结果,搜索用时 15 毫秒
161.
162.
Marcin Wierzchowski Daniel Ziental Dawid aewski Artur Korzanski Agnieszka Gielara-Korzanska Ewa Tykarska Jolanta Dlugaszewska Lukasz Sobotta 《International journal of molecular sciences》2022,23(11)
Newly developed tetra- and octasubstituted methimazole-phthalocyanine conjugates as potential photosensitizers have been obtained. Synthesized intermediates and final products were characterized by the MALD-TOF technique and various NMR techniques, including 2D methods. Single-crystal X-ray diffraction was used to determine the crystal structures of dinitriles. The studied phthalocyanines revealed two typical absorption bands—the Soret band and the Q band. The most intense fluorescence was observed for octasubstituted magnesium(II) phthalocyanine in DMF (ΦFL = 0.022). The best singlet oxygen generators were octasubstituted magnesium(II) and zinc(II) phthalocyanines (Φ∆ 0.56 and 0.81, respectively). The studied compounds presented quantum yields of photodegradation at the level between 10−5 and 10−6. Due to their low solubility in a water environment, the liposomal formulations were prepared. Within the studied group, octasubstituted zinc(II) phthalocyanine at the concentration of 100 µM activated with red light showed the highest antibacterial activity against S. aureus equal to a 5.68 log reduction of bacterial growth. 相似文献
163.
Nicolas Mireault Gilles Abel Lukasz Andrzejewski Guy Ross 《Microgravity science and technology》2005,16(1-4):219-223
The main purpose of this work is to clarify the controversy that has been widely discussed after the publication of Ward et al. [1, 2, 3] about whether varying g-levels should have an influence on contact angles of liquids on solid surfaces. Surface modification using PBII has been used to vary the contact angles of water on PMMA and CR-39 samples by implantation of O2 and Ar ions. Advancing and receding contact angles (θa and θr) have been measured using the injection and the withdrawn of a 3 μL water drop at a 2 μL/min rate on these PMMA and CR-39 samples, implanted or not. Analysis of the recorded frames of the whole parabola yielded the θa and θr vs g plots that are shown and discussed, while g-level vary from g~0.03 up to g~2.5. Comparison of the variable g hystereses with those measured in constant 1 g using the same samples is also made. Angle variations being lower than the measurement precision, the results indicate that the contact angles do not vary with g-level. 相似文献
164.
The two-spiral task is a well-known benchmark for binary classification. The data consist of points on two intertwined spirals which cannot be linearly separated. This article reviews how this task and some of its variations have significantly inspired the development of several important methods in the history of artificial neural networks. The two-spiral task became popular for several different reasons: (1) it was regarded as extremely challenging; (2) it belonged to a suite of standard benchmark tasks; and (3) it had visual appeal and was convenient to use in pilot studies. The article also presents an example which demonstrates how small variations of the two-spiral task such as relative rotations of the two spirals can lead to qualitatively different generalisation results. 相似文献
165.
Rafal Rak Lukasz A Kurgan Marek Reformat 《IEEE engineering in medicine and biology magazine》2007,26(2):47-55
The specific characteristic of classification of medical documents from the MEDLINE database is that each document is assigned to more than one category, which requires a system for multilabel classification. Another major challenge was to develop a scalable method capable of dealing with hundreds of thousand of documents. We proposed a novel system for automated classification of MEDLINE documents to MeSH keywords based on the recently developed data mining algorithm called ACRI, which was modified to accommodate multilabel classification. Five different classification configurations in conjunction with different methods of measuring classification quality were proposed and tested. The extensive experimental comparison showed superiority of methods based on reoccurrence of words in an article over nonrecurrent-based associative classification. The achieved relatively high value of macro F1 (46%) demonstrates the high quality of the proposed system for this challenging dataset. Accuracy of the proposed classifier, defined as the ratio of the sum of TP and TN examples to the total number of examples, reached 90%. Three scenarios were proposed based on the performed tests and different possible objectives. If a goal is to classify the largest number of documents, a configuration that maximizes micro F1 should be chosen. On the other hand, if a system is to work well for categories with a small number of documents, a configuration that maximizes macro F1 is more suitable. A tradeoff can be obtained by using a configuration that optimizes the average between macro and micro F1. 相似文献
166.
Gamma-secretase is an integral membrane protease, which is a complex of four membrane proteins. Improper functioning of gamma-secretase was found to be critical in the pathogenesis of Alzheimer's disease. Despite numerous efforts, the structure of the protease as well as its proteolytic mechanism remains poorly understood. In this work we constructed a model of interactions between two proteins forming gamma-secretase: APH-1 and presenilin. This interface is based on a highly conserved GxxxGxxxG motif in the APH-1 protein. It can form a tight contact with a small-residue AxxxAxxxG motif in presenilin. Here, four binding modes based on similar structures involving GxxxG motifs in glycophorin and aquaporin were proposed and verified. The resulting best model employs antiparallel orientations of interacting helices and is in agreement with the currently accepted topology of both proteins. This model can be used for further structural characterization of gamma-secretase and its components. 相似文献
167.
Wolfram Volk Peter Groche Alexander Brosius Andrea Ghiotti Brad L. Kinsey Mathias Liewald Lukasz Madej Junying Min Jun Yanagimoto 《CIRP Annals》2019,68(2):775-798
Modelling of metal forming processes is an essential task of production engineering. Due to the latest technological developments, a huge variety of models is already available and extending continuously. Thus, it is important to find a suitable model. This paper gives an overview on the common classification and characterization of modelling and models in metal forming, as well as introduces a model selection procedure. Based on this classification, various relevant process limits for metal forming are investigated regarding existing models. The conclusion of the paper shows open topics as well as upcoming challenges in modelling process limits in metal forming. 相似文献
168.
Standards Conformity Framework (SCF) presented in this paper encompasses methods and tools which provide support for application of standards and other normative documents. The approach taken focuses on development, assessment and maintenance of an electronic document which demonstrates conformity. Such a document contains an argument structure developed in accordance with the Trust-IT methodology. The paper discusses details of the SCF approach, provides the definition of SCF application processes, presents a developed software tool, which supports the method, and reports on the experience collected in numerous projects of application of the framework. 相似文献
169.
Brian Gordon Natalia Sobczak Malgorzata Warmuzek Andrzej Gazda Lukasz Boro Robert M.Purgert Jerzy J.Sobczak 《中国铸造》2010,7(4)
In this work the process of manufacturing a continuously reinforced cast Al matrix composite and its properties are presented.The described technology permits obtaining a structural material of competitive properties compared to either heat treatable aluminum alloys or polymer composites for several types of applications.The examined thermophysical properties and structural characterization,including material anisotropy,coupled with the results of previous measurements of the mechanical properties of both Al2O3reinforcing filaments and metallic prepregs have proven the high quality of this material and the possibility of its operation under special loading modes and environmental conditions.Microscopic examinations(LM,SEM)were carried out to reveal the range of morphological homogeneity of the microstructure,the anisotropy of the filament band distribution,and simultaneously the adhesive behavior of the metal/fiber interface.The 3D morphology of the chosen microstructure components was revealed by computed tomography.The obtained results indicate that special properties of the examined prepreg materials have been strongly influenced,on the one hand,by the geometry of its internal microstructure,i.e.spatial distribution and volume fraction of the Al2O3 reinforcing filaments and,on the other hand,by a very good compatibility obtained between the individual metal prepreg components. 相似文献
170.
MohammadHossein Bateni Lukasz Golab MohammadTaghi Hajiaghayi Howard Karloff 《Theory of Computing Systems》2011,49(4):757-780
We study scheduling algorithms for loading data feeds into real time data warehouses, which are used in applications such
as IP network monitoring, online financial trading, and credit card fraud detection. In these applications, the warehouse
collects a large number of streaming data feeds that are generated by external sources and arrive asynchronously. Data for
each table in the warehouse are generated at a constant rate, different tables possibly at different rates. For each data
feed, the arrival of new data triggers an update that seeks to append the new data to the corresponding table; if multiple updates are pending for the same table, they are
batched together before being loaded. At time τ, if a table has been updated with information up to time r≤τ, its staleness is defined as τ−r. 相似文献