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1.
王俭 《陶瓷研究》2020,(1):108-110
婴戏纹饰即描绘儿童游戏时的画作,是中国人物画的一种,更是陶瓷装饰中常见的传统题材。其主要以儿童为主要绘画对象,表现儿童纯真,或借以其他物象,组成吉祥图案,在我国陶瓷绘画上广泛运用,有着深刻的社会形态特征和思想文化的背景。其始于唐代,兴盛于宋金,明清两朝日臻成熟,并延续至今。在西方艺术史当中,儿童形象大都通过神话人物或宗教相关的艺术品走进人们视野,用以表现某些宗教思想或精神诉求。本文主要探讨陶瓷婴戏纹饰在我国历史发展历程中的演变概况,以及笔者对我国陶瓷婴戏纹饰和西方艺术品中儿童形象横向对比下的一些思考。  相似文献   
2.
This work aimed to clarify the interaction between the fetus and pregnant patients with gestational diabetes mellitus (GDM), the lipid metabolomics analysis of the fetal umbilical cord blood of GDM patients and normal pregnant women were performed to screen out the specific lipid metabolites for pathogenesis of GDM. From 2019–2020, 21 patients with GDM and 22 normal pregnant women were enrolled in Hexian Memorial Hospital, Panyu District, Guangzhou. The general information such as weight, height, age, body mass index (BMI) before pregnancy were analyzed. Non-targeted metabonomic detection and analysis were performed in umbilical cord plasma using LC-MS method. The age, BMI, delivery methods, and infant weight were different between GDM and control. There were 167 lipid metabolites in umbilical cord blood associated with GDM. Among them, 158 upregulated and 9 downregulated in GDM. There were 13 dysregulated metabolites with C < 30, including Lyso-phosphatidyl-colines LPC 16:0, 18:2, 18:1, 18:0, 20:4 and 22:6, glycerophosphocholines PC O-16:1, oleoylcarnitine CAR 18:2 and 18:1, dihexosylceramides Hex2Cer 13:0;2O, phosphatidylethanolamine PE O-22:6_2:0 and PE O-22:6_3:0 and sphingomyelin SM 8:0; 2O/11:0. Those metabolites were associated with glycerophospholipid metabolism and sphingolipid metabolism. Therefore, Lyso-phosphatidyl-colines, glycerophosphocholines, oleoylcarnitine, dihexosylceramides, phosphatidylethanolamine, and sphingomyelin were main lipid metabolites of GDM, which might be used for diagnosis and treatment of GDM.  相似文献   
3.
Docosahexaenoic acid (DHA)-rich diacylglycerol (DAG)-rich oil was prepared by lipase-catalyzed glycerolysis of microbial oil from Schizochytrium sp. in a solvent-free system. The reaction parameters including lipase type, substrate molar ratio, temperature, lipase concentration, and reaction time were screened. The selected conditions were determined as follows: Novozym® 435 (Novozymes A/S, Bagsvaerd, Denmark) as biocatalyst at 8 wt%, substrate ratio (DHA-rich microbial TAG/glycerol) of 1:1 mol/mol, temperature of 50 °C, and reaction time of 12 hours. Under these conditions, the triacylglycerol (TAG), DAG, and monoacylglycerol (MAG) contents in the product were 36.4%, 48.2%, and 15.4%, respectively. The lipase was reused successively for 18 cycles without significant loss of activity under the conditions given above. Fatty acid composition analysis of the final product showed that the contents of DHA in TAG, DAG, and MAG were 53.9%, 44.9%, and 34.8%, respectively. DHA-rich DAG has the potential to be used as an ingredient in infant formula to increase the bioavailability of DHA.  相似文献   
4.
The application of good hygiene practices for the reconstitution of infant formulae, preparation and consumption of feeding bottles, according to manufacturer’s instructions, is essential to ensure the microbiological safety and quality of feeding bottles. This study investigated the growth of Serratia marcescens, a bacterium widely present in home environments with the ability to cause pink coloration resulting from growth in intentionally contaminated reconstituted infant formulae, stored at 32 °C (as a simulation of inappropriate storage in tropical regions). In addition, poor hygiene practices such as lack of bottle wash after use, inadequate bottle washing and heat sanitisation, or use of contaminated kitchen cloths to wipe dry sterilised baby bottles were investigated as leading causes of microbial contamination and transfer during preparation of feeding bottles.Infant formulae powders represent a negligible risk of S. marcescens contamination, because finished product specifications require absence of Enterobacteriaceae (EB), and all lots are tested for absence of EB before release.The results of the simulation of inadequate hygiene practices during preparation of feeding bottles showed that bottles or reconstituted milk can be readily contaminated with S. marcescens by using a dirty cloth. The resulting contamination level in prepared milk was as high as 4 log CFU/mL. A similar contamination level was associated with inappropriate bottle washing and sanitation. Poor hygiene practices leading to such contamination levels are undesirable even if the feeding bottles are consumed immediately. S. marcescens was able to initiate grow in artificially inoculated infant formulae (3.2 log CFU/ml) within 4 h (lag-phase) and reach levels of 6 and 8 log CFU/ml after 8 h and 12 h at 32 °C respectively. A maximum growth rate of 0.42 h−1 was determined. The first sign of a distinctly pink discoloration was noticed at 32 °C within 24 h when cell concentration was above 9 log CFU/mL.To reduce microbial contamination during reconstitution of infant formulae it is strongly recommended to adhere to the 2007 FAO/WHO Guidelines on the Safe Preparation, Storage and Handling of Powdered Infant Formula and the instructions on the labels. In addition it is recommended to:
  • -Immediately discard milk of unfinished bottles, wash feeding bottles after use and let them dry out,
  • -Do not wipe bottles with kitchen cloths to dry after sanitisation.
  相似文献   
5.
The concentrations of major and trace elements in Argentinean commercial powdered milk samples were determined with inductively coupled plasma mass spectrometry. Also the daily intake (DI) was calculated for adults and infants. The concentrations of B, Mg, Na, K and Ca were significantly higher in skimmed milk. Cu, Mo, Fe, Mn and Zn were significantly higher in infant formula. All the DIs were below the tolerable upper intake levels. The mean As concentration (26.0 ± 8.6 ng/g) in the powdered skimmed milk samples was slightly higher than in the others. Mean Pb concentrations ranged from 4.1 ± 2.1 to 13.5 ± 8.2 ng/g. The highest mean U concentration was 7.8 ± 2.6 ng/g for whole milk. This study contributes to the knowledge of major and trace elements in powdered milk and its contribution to the diet in Argentina.  相似文献   
6.
Cadmium (Cd), lead (Pb) and arsenic (As) can enter the food chain through the environment and/or as a consequence of the manufacturing process making foodstuffs the main human exposure route to these chemical elements. The risk associated with this exposure is of such a big concern for human health that the European Food Safety Agency recommends to reduce the exposure to Cd and Pb so as to protect especially vulnerable subgroups of population (e.g., infants). Therefore, the setting of new maximum levels (MLs) for chemical elements in infant formulae (e.g., for Cd) or the reconsideration of the existing ML for Pb is under discussion. On this basis, the availability of analytical methods, precise, accurate and sensitive enough to quantify low concentration values, is a key point especially for official control laboratories that have to state the sample compliance using a fully validated method with an associated uncertainty compliant with the requirements specified in the pertinent regulations. This work describes the development and validation of an analytical method to quantify As, Cd and Pb in powdered infant formulae based on animal protein at values of concentration close to the MLs that are likely to be set. The results obtained make the method suitable for a precise and accurate determination of these chemical elements at these low concentration values. In particular, the results for limit of quantification (LoQ) were respectively (μg kg−1): As 6.2, Cd 1.2 and Pb 4.5. While for the recovery rates the following percentages were obtained: As 105%, Cd 98% and Pb 108%. The expanded uncertainties were found extremely satisfactory (Cd 13% and Pb 19%). The LoQ and the uncertainty for Pb meet the requirements set in Commission Regulation (EC) No. 333/2007 and following amendments being lower than the maximum values allowed. Even for Cd the expanded uncertainty resulted adequate in relation with the low concentration considered.  相似文献   
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9.
A peanut milk‐based infant formula was developed from peanuts. The effects of extraction pH and temperature on the yield and protein content of spray‐dried peanut milk were evaluated. Peanut‐based infant formulas (PBIF‐75) was developed using spray‐dried peanut milk and a premix of vitamins and minerals. Physical properties, approximate composition, minerals, vitamins and amino acid composition, and caloric value of PBIF‐75 were evaluated and compared to those of soya‐based infant formula (SBIF) and World Health Organization (WHO) F‐75. Spray‐dried peanut milk yield was 15–18% with a protein content of 30–45%, depending on the extraction pH and temperature. PBIF‐75 was nearly identical to WHO F‐75 in terms of amino acid profile, most vitamins and minerals, proximate composition, caloric value, and physicochemical characteristics such as water activity and colour. However, few of the vitamins and minerals in PBIF‐75 will require further adjustment to fully meet WHO’s requirements of a recovery formula for undernourished infants.  相似文献   
10.
As part of the programme on monitoring of environmental contaminants in food stuffs in Kuwait, 54 samples of fresh full cream and skimmed milk, powdered milk, yoghurt, and infant formula were analysed for aflatoxin M 1 (AFM 1 ) by HPLC following sample clean up using immuno-affinity columns. Of samples, 28% were contaminated with AFM 1 with 6% being above the maximum permissible limit of 0.2 μg l -1 . Three fresh cow milk samples collected from a private local producer showed the highest level of 0.21 μg l -1 AFM 1 . There was no contamination with AFM 1 in powdered milk and infant formulas. These results show the necessity of a survey involving a larger number of milk and its products and suggest that presently the contamination of milk and milk products with AFM 1 does not appear to be a serious health problem in Kuwait. Nevertheless, a continuous surveillance programme may be warranted to monitor regularly the occurrence of aflatoxins in the animal feeds responsible for current limited contamination and to note rapidly any worsening in the situation that may depend on market changes or on unfavourable climatic developments.  相似文献   
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