全文获取类型
收费全文 | 94篇 |
免费 | 9篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 31篇 |
金属工艺 | 1篇 |
建筑科学 | 2篇 |
矿业工程 | 1篇 |
能源动力 | 16篇 |
轻工业 | 33篇 |
无线电 | 2篇 |
一般工业技术 | 6篇 |
冶金工业 | 2篇 |
自动化技术 | 6篇 |
出版年
2022年 | 5篇 |
2021年 | 13篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 4篇 |
2013年 | 10篇 |
2012年 | 2篇 |
2011年 | 4篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 7篇 |
2007年 | 4篇 |
2006年 | 5篇 |
2005年 | 2篇 |
2003年 | 1篇 |
2002年 | 1篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1990年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有103条查询结果,搜索用时 0 毫秒
81.
Sezer Aysun Sezer Hasan Basri Albayrak Songul 《Neural computing & applications》2017,28(10):3021-3033
Neural Computing and Applications - The objective of this research is to develop a computer-based diagnosis system which is capable of recognizing normal and edematous humeral head images by using... 相似文献
82.
The concentrations of cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead and zinc were determined by ICP-AES in muscles and livers of 12 fish species sampled from the Marmara, Aegean and Mediterranean seas of Turkey. Iron showed the highest levels in examined tissues of all fish species. Following Fe, Zn generally showed the second highest levels. Metal concentrations in edible parts of fish species were 0.02–0.37 mg kg−1 for cadmium, 0.04–0.41 mg kg−1 for cobalt, 0.04–1.75 mg kg−1 for chromium, 0.32–6.48 mg kg−1 for copper, 7.46–40.1 mg kg−1 for iron, 0.10–0.99 mg kg−1 for manganese, 0.02–3.97 mg kg−1 for nickel, 0.33–0.86 mg kg−1 for lead, 4.49–11.2 mg kg−1 for zinc, respectively. All metal concentrations in livers were higher than those in muscles. In some stations, cadmium and chromium concentrations in both muscles and livers, and lead levels in livers of the examined species were higher than permissible safety levels for human uses. 相似文献
83.
The aim of this study was to investigate the microshear bond strength of five universal adhesives for use with demineralized enamel, with and without pre-etching. Using five universal adhesives (Single Bond Universal (SBU), Clearfil Universal (CU), Prime&Bond Elect Universal (PBU), Bisco All Bond Universal (ABU), Gluma Bond Universal (GU)), composite cylinders were bonded to the labial surfaces of extracted upper incisor teeth, with or without pre-etching. A micro-shear bond strength test was performed. The debonding surfaces were evaluated with the use of SEM. The data was analyzed using one-way ANOVA and Tukey’s Post-hoc tests. SBU, ABU, and PBU increased the bond strength statistically when used in etch&rinse mode (p?<?0.05). GU and CU did not change the bond strength statistically with the use of pre-etching (p?>?0.05). The bond strength of universal adhesives on demineralized enamel, with and without initial acid etching, depends on the type of adhesive system used. 相似文献
84.
Akko XIII is an important loquat variety grown in Turkey. As with many fruits and vegetables, enzymatic browning catalyzed by polyphenol oxidase (PPO) also occurs in loquats. PPO from Akko XIII loquat was extracted and purified through (NH4)2SO4 precipitation, dialysis and ion exchange chromatography. The enzyme showed several peaks with PPO activity on DEAE-Toyopearl 650 M column, of which only two (isoenzyme A and isoenzyme B) were characterized. Assay of activity of the isoenzymes between pH 3.04 and 7.80 using catechol as substrate showed two activity peaks, one at acidic pH and the other at neutral pH. pH optima of isoenzyme A and B were found to be at 7.4 and 4.98, respectively. The Km values of isoenzyme A and B using catechol as substrate were found to be 152.3 mM and 5.4 mM, respectively. They both displayed maximal activity at 30oC. The two isoenzymes displayed different heat resistance and sensitivity towards various inhibitors. 相似文献
85.
Lars Herrmann Dr. Ivan A. Yaremenko Dr. Aysun Çapcı Julia Struwe Dhanir Tailor Arpit Dheeraj Dr. Jan Hodek Yulia Yu. Belyakova Dr. Peter S. Radulov Dr. Jan Weber Prof. Dr. Sanjay V. Malhotra Prof. Dr. Alexander O. Terent'ev Prof. Dr. Lutz Ackermann Prof. Dr. Svetlana B. Tsogoeva 《ChemMedChem》2022,17(9):e202200005
The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause life-threatening diseases in millions of people worldwide, in particular, in patients with cancer, and there is an urgent need for antiviral agents against this infection. While in vitro activities of artemisinins against SARS-CoV-2 and cancer have recently been demonstrated, no study of artemisinin and/or synthetic peroxide-based hybrid compounds active against both cancer and SARS-CoV-2 has been reported yet. However, the hybrid drug's properties (e. g., activity and/or selectivity) can be improved compared to its parent compounds and effective new agents can be obtained by modification/hybridization of existing drugs or bioactive natural products. In this study, a series of new artesunic acid and synthetic peroxide based new hybrids were synthesized and analyzed in vitro for the first time for their inhibitory activity against SARS-CoV-2 and leukemia cell lines. Several artesunic acid-derived hybrids exerted a similar or stronger potency against K562 leukemia cells (81–83 % inhibition values) than the reference drug doxorubicin (78 % inhibition value) and they were also more efficient than their parent compounds artesunic acid (49.2 % inhibition value) and quinoline derivative (5.5 % inhibition value). Interestingly, the same artesunic acid-quinoline hybrids also show inhibitory activity against SARS-CoV-2 in vitro (EC50 13–19 μm ) and no cytotoxic effects on Vero E6 cells (CC50 up to 110 μM). These results provide a valuable basis for design of further artemisinin-derived hybrids to treat both cancer and SARS-CoV-2 infections. 相似文献
86.
Biochemical characteristics of polyphenol oxidase (PPO) from Narince grapes were studied in two consecutive years (2006 and 2007). The optimum pH and temperature of the two PPOs were found to be same (5.49 and 45 °C). The apparent substrate specificities were established from Vmax/Km as follows: caffeic acid > 4-methylcatechol > catechol > pyrogallol for two enzymes. There were marked differences between the two enzymes in terms of thermal stability. The effects of inhibitors varied in a dose-dependent manner. The degree of inhibition exerted by the inhibitors tested varied according to the harvest year. 相似文献
87.
Analysis and optimization of surface roughness in the ball burnishing process using response surface methodology and desirabilty function 总被引:1,自引:0,他引:1
Aysun Sagbas 《Advances in Engineering Software》2011,42(11):992-998
In the present study, an optimization strategy based on desirability function approach (DFA) together with response surface methodology (RSM) has been used to optimize ball burnishing process of 7178 aluminium alloy. A quadratic regression model was developed to predict surface roughness using RSM with rotatable central composite design (CCD). In the development of predictive models, burnishing force, number of passes, feed rate and burnishing speed were considered as model variables. The results indicated that burnishing force and number of passes were the significant factors on the surface roughness. The predicted surface roughness values and the subsequent verification experiments under the optimal conditions were confirmed the validity of the predicted model. The absolute average error between the experimental and predicted values at the optimal combination of parameter settings for surface roughness was calculated as 2.82%. 相似文献
88.
The presence of zinc oxide in rubber compounds is tried to be minimized due to environmental concerns. In this study; the effect of different zinc oxide types on ageing properties of SBR compounds was investigated. Active zinc oxide and zinc oxide coat on CaCO3 core were used in SBR compounds and their ageing characteristics were compared. The changes in tensile properties, hardness and rebound resilience were followed and evaluated. 相似文献
89.
Guner Ozay Ferda Seyhan Ceyda Pembeci Sena Saklar Aysun Yilmaz 《Food Additives & Contaminants》2008,25(2):209-218
The levels aflatoxins in Turkish hazelnuts have been monitored over a 3-years period (2002-2004). Periodical sampling was made in 72 different orchards at different locations representative of the hazelnut-growing areas and post-harvest applications. Various parameters (aflatoxins, water activity, moulds) were analysed and environmental conditions (temperature and relative humidity) recorded during growing and at different stages of harvest and post-harvest processing, involving three different harvesting methods (collection in nets, from the ground, etc.) and four drying techniques (traditional sun-drying, mechanical drying, etc.). Fungal and aflatoxin analyses (HPLC) showed no significant difference except between samples which had been in contact with the ground and those which had not (at 95% confidence level). Aflatoxins levels from the orchard recorded a maximum of 0.77 ± 0.08 ng g-1 from a total of 1624 samples. Regarding harvesting and post-harvest processes, the only application where aflatoxins were detected was in samples which had been in direct contact with the ground (max. 3.18 ± 0.03 ng g-1). Aflatoxin formation was low during storage (max. 0.34 ± 0.003 ng g-1). As a result of mycological studies, a total of 5546 Aspergillus flavus (89%) and A. parasiticus (11%) species were isolated and identified from samples. The results indicated that harvesting hazelnuts into a canvas by shaking the trees, manual harvesting of mature hazelnuts where possible, use of jute instead of nylon sacks and mechanical drying technique would minimize aflatoxin levels in hazelnuts. These recommendations have been implemented and about 4000 people in the hazelnut industry have been trained in these practices. 相似文献
90.
Textiles, with appropriate light absorbers and suitable finishing methods, can be used as ultraviolet (UV) protection materials. In this study, we investigated the effects of nano‐TiO2 particles on the UV‐protective and structural properties of polypropylene (PP) textile filaments. Master batches of PP/TiO2 nanoparticles were prepared by melt compounding before spinning, and filaments incorporating 0.3, 1, and 3% TiO2 nanoparticles were spun in a pilot melt‐spinning machine. The structural properties of the nanocomposite fibers were analyzed with scanning electron microscopy, X‐ray diffractometry, differential scanning calorimetry, and tensile tests. The UV‐protection factor was determined to evaluate the UV‐protective properties of the filaments. In conclusion, although the structure and mechanical properties of the nanocomposite filaments were slightly affected by the addition of nano‐TiO2, the UV‐protective properties of the PP filaments improved after treatment with nano‐TiO2, and the nanocomposite filaments exhibited excellent UV protection. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献