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61.
Tomasz Jagielski Katarzyna Roeske Zofia Bakuła Tomasz Piech Łukasz Wlazło Mariola Bochniarz Piotr Woch Henryk Krukowski 《Journal of dairy science》2019,102(1):619-628
Prototheca mastitis has recently become an emerging disease; although its incidence is increasing steadily, its epidemiology remains largely understudied. The aim of this work was to investigate the prevalence of Prototheca spp. in dairy cows and their environment in Lublin province, covering most of southeastern Poland. Between December 2015 and July 2016, a total of 172 milking cows from 10 dairy farms were inspected for mastitis using clinical examination and the California Mastitis Test (CMT). Quarter milk samples (QMS, n = 179) and body site swabs (n = 151) from CMT-positive cows were collected for microbiological culture. In addition, we evaluated QMS and body site swabs from 23 healthy cows, along with 91 environmental samples. Of 100 CMT-positive cows, 71 had at least one QMS positive for microbial growth. In 8 (11.3%) of these cows, originating from 7 dairy farms, Prototheca spp. were cultured. The average somatic cell count of the Prototheca-containing milk was 4.02 × 106 cells/mL compared with 0.13 × 106 cells/mL of the Prototheca-free milk (collected from control animals). No significant differences were observed between mastitis and control cows with respect to counts of total white blood cells, lymphocytes, neutrophils, and eosinophils. Half of the cows with Prototheca spp. in their milk did not yield the algae from other anatomical sites. Eight cows were negative for the presence of Prototheca spp. in their milk but positive for the algae in swabs from anatomical sites. Among the environmental sources that were positive for Prototheca growth were watering troughs, manure, feed, and mud. All (45) Prototheca isolates recovered in this study were subjected to species- and genotype-level molecular identification. All QMS and most of the animal swabs (90%) yielded Prototheca zopfii genotype (gen.) 2. Of the animal samples, P. zopfii gen. 1 and Prototheca blaschkeae were isolated only from feces and rectum. Environmental samples grew either P. zopfii gen. 2 (67%) or P. zopfii gen. 1 (33%). This study demonstrates that P. zopfii gen. 2 is the third most common pathogen of mastitis in cattle in southeast Poland, with an overall incidence of 4.6%. Finding Prototheca spp., including P. zopfii gen. 1 and 2 and P. blaschkeae, in stool and rectal swabs from healthy animals may suggest their role as nonpathogenic microflora of bovine gut. 相似文献
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64.
Paulina Cholewinska Marta Michalak Deta Łuczycka Katarzyna Czyż 《Journal of Natural Fibers》2020,17(3):382-388
ABSTRACTThe phenomenon of impedance finds an application in many areas of science; however, no studies relate to wool. Thus, the aim of the study was an examination of an effect of from the presence of suint layer on sheep wool fibers on impedance and heat resistance values. Electrical characteristics (impedance [Ω]) and heat resistance were compared in terms of wool washing effect. The impedance of wool samples was tested in the frequency range of 10 Hz to 1 MHz. In order to measure electrical characteristics and heat resistance values, five samples of greasy wool were collected from different sheep breeds, standardized by weight. After the analyses, the samples were washed and reexamined. The results showed significant differences in the impedance between the greasy and washed wool samples in each of the tested breed (p > 0.05). The suint layer reduces the impedance level, which was also confirmed by a heat resistance test results demonstrating that absence of suint layer on wool fibers significantly reduced this feature value (p > 0.05). This was also reflected in the weight differences between the examined wool samples before and after their washing. 相似文献
65.
Sławomir Wybraniec Karolina Starzak Anna Skopińska Maciej Szaleniec Jacek Słupski Katarzyna Mitka Piotr Kowalski Tadeusz Michałowski 《Food science and biotechnology》2013,22(2):353-363
An effect of metal cations on betanin stability was investigated in aqueous and organic-aqueous solutions. The presence of organic solvents (methanol, ethanol, and acetonitrile) affects substantially the pigments decomposition in acidic media induced by metal cations whose degrading action in such media is significantly higher than in aqueous solutions. The influence of Cu2+ on the stability was studied by spectrophotometry in more detailed manner, because of its ability to form complexes with betanin. The possibility of a complex formation between betanin and Ni2+ was also stated at pH 7–8; its relatively high stability in aqueous samples was observed. A presence of numerous products of betanin decomposition was detected in the wavelength range 380–500 nm in spectra obtained for most of metal cations investigated, especially for higher concentrations of the organic solvents. 相似文献
66.
Mi-Na Cha Hyun-Il Jun Won-Jae Lee Min-Ji Kim Myung-Kon Kim Young-Soo Kim 《Food science and biotechnology》2013,22(2):523-529
The chemical composition and antioxidant activities of the Korean cactus (Opuntia humifusa, OH) fruit were investigated in this study. Major minerals in the OH fruit were P, Ca, and Mg. Total dietary fiber content was 22.8% and the soluble dietary fiber/insoluble dietary fiber ratio was 1:1.3. An 80% ethanol extract was used to investigate antioxidant activities based on DPPH radical scavenging ability as well as total phenolic and flavonoid content. OH fruit extract from 80% ethanol was sequentially fractionated according to the polarity of solvents. Among various fractions, the ethyl acetate fraction showed the highest antioxidant activity as well as the highest total phenolic and total flavonoid contents compared to other fractions. The most abundant phenolic acid in the ethyl acetate fraction was ferulic acid, followed by protocatechuic acid. The most abundant flavonoid was taxifolin, followed by myricetin. The results suggested that OH fruit could be a good potential source of antioxidant. 相似文献
67.
Maria Balcerek Katarzyna Pielech‐Przybylska Piotr Patelski Ewelina Sapińska Mirosława Księżopolska 《Journal of food science》2013,78(5):S770-S776
In this study, an evaluation of intermediate products of plum processing as potential raw materials for distillates production was performed. Effects of composition of mashes on ethanol yield, chemical composition and taste, and flavor of the obtained spirits were determined. The obtained results showed that spontaneous fermentations of the tested products of plum processing with native microflora of raisins resulted in lower ethanol yields, compared to the ones fermented with wine yeast Saccharomyces bayanus. The supplementation of mashes with 120 g/L of sucrose caused an increase in ethanol contents from 6.2 ± 0.2 ÷ 6.5 ± 0.2% v/v in reference mashes (without sucrose addition, fermented with S. bayanus) to ca. 10.3 ± 0.3% v/v, where its highest yields amounted to 94.7 ± 2.9 ÷ 95.6 ± 2.9% of theoretical capacity, without negative changes in raw material originality of distillates. The concentrations of volatile compounds in the obtained distillates exceeding 2000 mg/L alcohol 100% v/v and low content of methanol and hydrocyanic acid, as well as their good taste and aroma make the examined products of plum processing be very attractive raw materials for the plum distillates production. 相似文献
68.
El?bieta?Lipiec Olga?Warowicka Lena?RuzikEmail author Ying?Zhou Maciej?Jarosz Katarzyna?Po?e?-Pawlak 《European Food Research and Technology》2012,234(5):913-919
The goal of the presented studies was to investigate speciation and bioavailability of iodine from chicken eggs versus iodized kitchen salt with an in vitro method. Determination of iodine total content in chicken eggs and iodized kitchen salt
was carried out by inductively coupled plasma mass spectrometry (ICP MS). The majority of iodine was accumulated in the yolk—the
concentration was even 37 times higher than in white. Chicken eggs were treated with buffer (Tris HCl pH = 7.5) and enzymatic
extraction media and analyzed by size exclusion chromatography hyphenated with inductively coupled plasma mass spectrometry
(SEC ICP MS). The enzymatic extraction being an in vitro bioavailability assessment method was based on two-stage digestion
model simulating gastric (pepsin digestion) and intestinal (pancreatin digestion) juices. Speciation analyses along with bioavailability
studies presented iodide as the major form in chicken eggs. The bioavailability was established as 33% from white and 10%
from yolk and decreased with longer time of boiling. It allows to suggest that the majority of iodine remains in forms bound
to non-digestible coagulated and water-insoluble proteins. 相似文献
69.
Siet J. Sijtsema Katarzyna Jesionkowska Ronan Symoneaux Dorota Konopacka Harriëtte Snoek 《LWT》2012,49(2):275-281
Dried fruits consumption has not received much research attention, although these foods are associated with potential health benefits. Therefore, the aim of this study was to compare fresh fruits and dried fruits on measures of health, convenience and consumer feelings.An on-line questionnaire that measured consumers' perceptions of the health benefits and convenience characteristics and their feelings about the consumption of both fresh fruits (apples and plums) and dried fruits (e.g., raisins, dates, and apricots) was completed by 693 respondents (Polish, French, and Dutch).Generally, fresh fruits were perceived to be healthier and less convenient than dried fruits. Consumers also reported more positive feelings about the consumption of fresh fruits compared to dried fruits. The more that the respondents were willing to sacrifice for their health, the more positively they rated the health aspects of both fresh and dried fruits, as well as several perceptions of convenience of both fresh and dried fruits. Health preoccupation was unrelated to most of the convenience perceptions and was associated with lower scores on several perceptions of healthiness. Recommendations for the consumer-oriented development of dried fruits are also provided. 相似文献
70.
Joanna Milala Katarzyna Grzelak‐Błaszczyk Michał Sójka Monika Kosmala Agnieszka Dobrzyńska‐Inger Edward Rój 《Journal of Food Processing and Preservation》2018,42(1)
The objective of the work was to elucidate the chemical composition of fractions of oil extracts obtained during the supercritical extraction on a semi‐industrial scale from strawberry (Fragaria x ananassa Duch.), chokeberry [Aronia melanocarpa (Michx.)], and raspberry (Rubus idaeus L.) seeds from industrial press cake. The oil extracts differed in terms of their content of bioactive components: carotenoids, tocopherols, chlorophylls, and fatty acids. Raspberry seed oil was the richest source of tocopherols (620.1–2166.7 mg kg?1) and α‐linolenic acid (above 37%). Chokeberry seed oil had the highest content of linoleic acid (above 70%), and α‐tocopherol (166.0–1104.8 mg kg?1). Strawberry oil was characterized by the highest content of chlorophylls and α‐linolenic acid (above 30%). It was showed that the oil fraction collected at the beginning of extraction is characterized by a high acid value, which requires purification steps to be used for food purposes.