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61.
Sulphur dioxide (SO2) is an important atmospheric pollutant, and capture of SO2 is of great importance for the environment, human health and market. Carbon based materials, especially activated carbon, are mostly used for adsorption purposes. However, there is a notable lack on adsorption of SO2 on graphene oxide (GO) fibers and fiber web surface. In this study, the effect of addition of activated carbon, pH of GO dispersions, hydrazine reduction and oxygen/argon plasma treatment on SO2 adsorption of GO fiber web surface were evaluated. It was seen that GO fiber web surface with activated carbon provides high SO2 adsorption (896 mg SO2/g) which is very higher than many of carbon based materials presented in the literatures. Single coagulation bath increases surface roughness of fiber and provides higher functional group than three coagulation baths leading to higher SO2 adsorption capacity.  相似文献   
62.
In this study, the aim was to characterize the physicochemical properties and some bioactive compounds of expeller-pressed oils of five registered poppy seed varieties (TMO–1, Ofis–8, Ofis–96, Ofis–95, Ofis–3) grown in Turkey. The amounts of total carotenoids, chlorophylls, phenols, and antioxidant activities of oils ranged between 0.08–0.24 mg 100 g−1, 0.03–9.04 mg pheophytin a kg−1, 3.41–8.57 mg gallic acid equivalent 100 g−1, and 5.60–7.33 mM Trolox equivalent 100 g−1, respectively. The most abundant fatty acid in poppy seed oils was linoleic acid (69.85–74.02%), followed by oleic acid (13.98–16.99%), and palmitic acid (8.51–9.75%). In addition, poppy seed oils were rich in β–sitosterol (133.47–153.42 mg 100 g−1), campesterol (45.36–58.60 mg 100 g−1), and δ–5–avenasterol (28.21–39.40 mg 100 g−1). High amounts of γ–tocopherol and α–tocopherol were detected. This research is the first study, which identified and quantified the polyphenol, β–carotene, and lutein compounds of expeller–pressed poppy seed oils by HPLC. Tyrosol, apigenin, syringic acid, 3–hydroxytyrosol, luteolin, p–coumaric acid, quercetin, ferulic acid, sinapic acid, and veratric acid were detected in expeller-pressed poppy seed oils.  相似文献   
63.
The compositions of fatty acids, tocopherols, polyphenols, sterols, and the total phenol contents of cold pressed oils obtained from five varieties of safflower seeds and ten varieties of camelina seeds cultivated in Turkey were determined. Total phenol contents of safflower oils were higher (272.20–525.30 mg GAE/kg) than camelina seed oils (25.90–63.70 mg GAE/kg). Apigenin, luteolin, tyrosol, syringic acid, 3-hydroxytyrosol, p-coumaric acid and sinapic acid were detected in seed oils. Camelina seed oils were rich in tocopherol (144.11–168.69 mg/100 g). γ-Tocopherol was the predominant tocopherol in camelina seed oils consisting of averagely 80% of total tocopherol, while α-tocopherol was the main compound of safflower seed oils, representing 97.85–98.53% of total tocopherols. β-Sitosterol was the major sterol in both type of seed oils. Its concentration ranged between 92.51–121.83 mg/100 g and 80.52–25.54 mg/100 g in safflower seed and camelina oils, respectively. Camelina seed oils contained 22.31–26.57% linolenic acid, 21.25–24.05% linoleic acid and 19.46–21.47% oleic acid, whereas safflower seed oils mainly consisted of linoleic (28.03–76.85%) and oleic (13.01–62.61%) acids.  相似文献   
64.
Breast cancer can be effectively detected and diagnosed using the technology of digital mammography. However, although this technology has been rapidly developing recently, suspicious regions cannot be detected in some cases by radiologists, because of the noise or inappropriate mammogram contrast. This study presents a classification of segmented region of interests (ROIs) as either benign or malignant to serve as a second eye of the radiologists. Our study consists of three steps. In the first step, spherical wavelet transform (SWT) is applied to the original ROIs. In the second step, shape, boundary and grey level based features of wavelet (detail) and scaling (approximation) coefficients are extracted. Finally, in the third step, malignant/benign classification of the masses is implemented by giving the feature matrices to a support vector machine system. The proposed system achieves 91.4% and 90.1% classification accuracy using the dataset acquired from the hospital of Istanbul University in Turkey and the free Mammographic Image Analysis Society, respectively. Furthermore, discrete wavelet transform, which produces 83.3% classification accuracy, is applied to the coefficients to make a comparison with the SWT method.  相似文献   
65.
The paper contributes to an emerging literature that critically questions the degree to which R&D, at the centre of national and transnational innovation policies, results in firm growth. The differences in how innovation affects firm growth is explored for small and large publicly quoted US pharmaceutical firms between 1950 and 2008. We observe that the positive impact of R&D on firm growth is highly conditional upon a combination of firm-specific characteristics such as firm size, patenting and persistence in patenting. For small firms, R&D boosts growth for only a subset of firms: namely, those that patent persistently for a minimum of five years. For large pharmaceutical firms, on the other hand, R&D may have a negative impact on growth; potentially resulting from the low R&D productivity these firms have suffered from since the mid-1990s. These results raise important issues around the R&D and firm growth relationship for small and large firms as well the role of persistence in innovation for boosting firm performance.  相似文献   
66.
This study assesses the level of background radiation for Kayseri province of Turkey. Natural radionuclide activity concentrations in soil samples were determined using high-resolution gamma spectroscopy. Outdoor gamma dose measurements in air at 1 m above ground level were determined using a portable gamma scintillation detector. The obtained results of uranium and thorium series as well as potassium ((40)K) are discussed. The present data were compared with the data obtained from different areas in Turkey. From the measured gamma-ray spectra, the average activity concentrations were determined for (238)U (range from 3.91 to 794.25 Bq kg(-1)), (232)Th (range from 0.68 to 245.55 Bq kg(-1)) and (40)K (range from 23.68 to 2718.71 Bq kg(-1)). The average activity concentrations of (238)U, (232)Th and (40)K were found to be 35.51, 37.27 and 429.66 Bq kg(-1), respectively, and 11.53 Bq kg(-1) for the fission product (137)Cs. The highest values of (238)U, (232)Th and (40)K concentrations (794.25 Bq kg(-1), 245.55 Bq kg(-1), 2718.71 Bq kg(-1), respectively) were observed in abnormal samples at Hayriye village. The average outdoor gamma dose rate in air at 1 m above the ground was determined as 114.43 nGy h(-1). Using the data obtained in this study, the average annual effective dose for a person living in Kayseri was found to be about 140.34 μSv.  相似文献   
67.
The objective of the present study was to obtain data about cooking time and temperature of kiymali pide in the restaurants and to investigate thermal inactivation of E. coli O157:H7 during experimental kiymali pide making. A field study was conducted in randomly selected 23 of 87 pide restaurants. Processing parameters including oven temperature, cooking period and post-cooking temperature were determined. Kiymali pide samples were prepared using ground beef filling experimentally inoculated with E. coli O157:H7 (7.6 log10 CFU/g). Pide samples were cooked at a conventional oven at 180 °C for 180, 240, 270, 300 and 330 s. Results of the current study suggest that cooking kiymali pide at 180 °C for at least 330 s (5.5 min) may provide sufficient food safety assurance (≥ 6 log10 CFU/g) for E. coli O157:H7.  相似文献   
68.
Third party logistics service providers (3PLs) have an important role in supply chain management. Increasing cooperation with 3PLs is expanding in today’s business environment. Hence, 3PLs need to have an efficient distribution network to meet customer demands. Nevertheless, few researches have tried to propose a solution for distribution network problems of 3PLs. The optimization problem which is discussing in our study is solved in two stages. At the first stage, the assignment problem which includes assigning the order of the vehicles is solved with mixed integer programming by using GAMS 21.6/CPLEX. The output of the first stage is used as an input in the second stage. In this stage routes are determined for vehicles by developing a genetic algorithm by using C#.  相似文献   
69.
There is a group of animal fibers known as “luxury fibers.” These are mohair, cashmere, camel hair, lama, alpaca, vicuna, guanaco, angora, yak, and quivit. In this study, the effects of demographical variables such as gender, education, age, sector, and income on the recognition and usage of luxury fibers in Thrace Region of Turkey were investigated. In order to analyze the obtained data, crosstabulation and chi-square statistical methods are used. According to the experimental results it can be said that the most commonly known and used luxury fibers are cashmere, mohair, and angora. The most important (37.6%) reason for participants to use luxury fibers is their warm feeling. On the other hand the most important (approx. 30%) reason for participants not to use them is that they do not have sufficient information about these fibers. It was determined that the most commonly (37.8%) used textile product made of luxury fibers is outerwear. Furthermore, it was found out that approximately 75% of participants accept paying more for garment containing luxury fibers because of their high quality.  相似文献   
70.
Fruit juices are generally concentrated in order to improve the stability during storage and to reduce handling, packaging, and transportation costs. Thermal evaporation is the most widely used technique in industrial fruit juice concentrate production. In addition to high energy consumption, a large part of the characteristics determining the quality of the fresh juice including aroma, color, vitamins, and antioxidants undergoes remarkable alterations through the use of high operation temperatures. Increasing consumer demand for minimally or naturally processed stable products able to retain as much possible the uniqueness of the fresh fruit has engendered a growing interest for development of nonthermal approaches for fruit juice concentration. Among them, membrane distillation (MD) and its variants have attracted much attention for allowing very high concentrations to be reached under atmospheric pressure and temperatures near ambient temperature. This review will provide an overview of the current status and recent developments in the use of MD for concentration of fruit juices. In addition to the most basic concepts of MD variants, crucial suggestions for membrane selection and operating parameters will be presented. Challenges and future trends for industrial adaptation taking into account the possibility of integrating MD with other existing processes will be discussed.  相似文献   
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