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We performed a macroscopic and microscopic study of the tongues of common opossums, Didelphis marsupialis, from South America. We studied two males and two females. We collected morphometric data on the tongue with precision calipers. For the light microscopy and scanning electron microscopy analyses, we fixed tissue fragments in 10% formaldehyde and 2.5% glutaraldehyde, respectively. The opossum tongues averaged 5.87 ± 0.20 cm in length, 3.27 ± 0.15 cm in width at the lingual body, and 3.82 ± 0.15 cm in width at the root. The mean thickness of the lingual body was 1.8 ± 0.1 cm, and the thickness of the root was 3.82 ± 0.15 cm. Sharp filiform papillae were scattered across the entire tongue; conical filiform papillae occurred on the lingual body and tongue tip; fungiform papillae were scattered among the filiform papillae on the lingual body and tongue tip; and there were three vallate papillae at the root of the tongue. We found two strands of papillary projections in the tongue root. Despite the low variability observed in the lingual papillae, the morphological data obtained in this study may be related to the opossum's diverse food habits and the extensive geographic distribution of the species throughout America. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
3.
槐米色素对羊毛织物的染色工艺设计   总被引:2,自引:0,他引:2  
研究了槐米色素对羊毛织物的染色性能。以表面色深度(K/S)更深、染色牢度更好、颜色更黄(b*)为要求,探讨染液pH值、媒染剂、染色温度及染料用量对槐米染羊毛织物染色性能的影响。研究结果表明,在浴比1∶30条件下,槐米染料对羊毛织物的染色适宜的染液pH值为4~6,宜采用铝后媒染色,且媒染剂的用量为5%(o.w.f)左右,...  相似文献   
4.
Genetically modified (GM) canola is the most widely grown oilseed crop in Canada. At this time, commercially produced GM canola cultivars in Canada have the events GT73/RT73 and Ms8xRf3. Commercial seed sale of canola cultivars containing the GM events such as OXY235 and T45 has been discontinued. Adventitious presence of GM seeds and grains in non-GM grains is a concern for international grain trade, and development of effective detection methods is important. A multiplex qualitative PCR procedure was established for the detection of the GM canola events OXY235, Ms8xRf3, T45 and GT73. The presence of the GM canola events was also successfully detected in ground spiked wheat and barley grain samples prepared at 0.1%, 0.5% and 1.0% levels (w/w). The GT73 real-time PCR assay was successfully used to quantify DNA extracted from spiked ground canola samples consisting of 5%, 1%, 0.5% and 0.1% GT73 (w/w).  相似文献   
5.
Surface ultrastructure of the gills of the angler catfish Chaca chaca was investigated to unravel the adaptive modifications associated with the feeding ecology of the fish. The fish is often found in mud or in soft substrates where they remain buried both for protection and to feed. Gill rakers present on the gill arch in most fish species are absent in this fish. The absence of gill rakers are associated with the feeding habit of the fish and is considered to facilitate the swallowing of captured prey smoothly without any hindrance. Highly corrugated surface of the gill arch and gill filaments could be associated to retain water/mucus to prevent dessicassion of the fish. Papillae like epithelial protuberances each bearing a taste bud at its summit toward the pharyngeal side of the gill arch is associated with the sorting of the food. Large number of mucous goblet cells on the gill arch epithelium are considered to secret copious mucus to lubricate the prey for easy swallowing. In C. chaca the gill septa between gill filaments are reduced. This could enhance the flexibility and permit the free movement of the gill filaments. Extensive secondary lamellae and infrequent mucous goblet cells on secondary lamellae are associated to increase the surface area to enhance efficiency of gaseous exchange.  相似文献   
6.
研究双乙酸钠、乳酸双芽菌和脉冲强光杀菌处理在煎制鲤鱼4 ℃贮藏过程中的保鲜效果。通过用双乙酸钠(1.1 g/100 mL)、乳酸双芽菌(0.21 g/100 mL)结合脉冲强光杀菌(能量590 J,距离9 cm)对煎制鲤鱼鱼块进行处理,定期分析对照组和处理组样品的pH值、硫代巴比妥酸反应物(thiobarbituric acid reactive substance,TBARs)值、挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、质构和感官属性等指标。结果表明:与对照组样品比,双乙酸钠结合脉冲强光杀菌处理组样品具有较低的pH值以及较高的水分含量,而乳酸双芽菌结合脉冲强光杀菌处理组样品的菌落总数较低,其水分分布也优于对照组,处理组均能有效地保存煎制鲤鱼;然而,双乙酸钠、乳酸双芽菌结合脉冲强光杀菌处理在贮藏期间表现出更好的抗菌效果,其显示出更强的抑制TBARs值和TVB-N含量升高的能力,且样品的质构和感官属性最好。因此,为延缓冷藏期间煎制鲤鱼的变质,双乙酸钠、乳酸双芽菌结合脉冲强光杀菌处理更为有效。  相似文献   
7.
槐米染料的染色性能及对毛织物的染色工艺   总被引:5,自引:0,他引:5       下载免费PDF全文
为研究槐米染料的产业化应用,测试了天然槐米染料的化学成分以及耐热、耐酸碱稳定性,分析了染色温度、pH值、媒染剂用量、染料用量等染色工艺参数对毛织物染色效果的影响,并测试了槐米染色毛织物的抗菌性能。研究结果表明:采用简单的制备方法,就能得到纯度高、耐热稳定性较好的槐米粉末染料;采用优化的铝预媒染色工艺可染得色泽鲜艳、牢度较好的黄色毛织物,且染色毛织物对金黄色葡萄球菌具有杀菌功能,对大肠杆菌、白色念珠菌具有抑菌作用。  相似文献   
8.
“食无定味,适口者珍”是先贤对烹饪调味的经验总结,但现代人过分追求味的刺激反而对身体健康不利,文章通过对传统调味养生学说的研究,初步探求了调味与养生的关系。  相似文献   
9.
为了刻蚀出低损耗波导沟道,对光刻和反应离子束蚀刻(RIE)中影响展宽的工艺条件进行理论分析和实验实践,提出采用多次旋涂、消除芽孢、低温后烘和刻蚀、光学稳定等措施减小展宽,并对不能完全消除的展宽分析给出原因。实验结果表明展宽得到有效的改善。  相似文献   
10.
A step forward in the knowledge about the underlying physiological phenomena of thoracic sounds requires a reliable estimate of their time–frequency behavior that overcomes the disadvantages of the conventional spectrogram. A more detailed time–frequency representation could lead to a better feature extraction for diseases classification and stratification purposes, among others. In this respect, the aim of this study was to look for an omnibus technique to obtain the time–frequency representation (TFR) of thoracic sounds by comparing generic goodness-of-fit criteria in different simulated thoracic sounds scenarios. The performance of ten TFRs for heart, normal tracheal and adventitious lung sounds was assessed using time–frequency patterns obtained by mathematical functions of the thoracic sounds. To find the best TFR performance measures, such as the 2D local (ρmean) and global (ρ) central correlation, the normalized root-mean-square error (NRMSE), the cross-correlation coefficient (ρIF) and the time–frequency resolution (resTF) were used. Simulation results pointed out that the Hilbert–Huang spectrum (HHS) had a superior performance as compared with other techniques and then, it can be considered as a reliable TFR for thoracic sounds. Furthermore, the goodness of HHS was assessed using noisy simulated signals. Additionally, HHS was applied to first and second heart sounds taken from a young healthy male subject, to tracheal sound from a middle-age healthy male subject, and to abnormal lung sounds acquired from a male patient with diffuse interstitial pneumonia. It is expected that the results of this research could be used to obtain a better signature of thoracic sounds for pattern recognition purpose, among other tasks.  相似文献   
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