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1.
New cultured ornamental fish namely Lake Kurumoi rainbowfish Melanotaenia parva (Allen) run into reduced of colour performances when reared in the aquaria, consequently, fish feed must be added with carotenoids as a pigment source. The aim of this study was to evaluate the digestibility, growth and pigmentation of astaxanthin, canthaxanthin and lutein in diet. Apparent digestibility coefficients (ADC) of dry matter, lipid, protein, carotenoids, growth and pigmentation were studied in twenty fish after 14 and 56 days of observation. The single‐dose supplementation of 100 mg/kg of astaxanthin, canthaxanthin, or lutein diets on fish was fed by apparent satiation. The basal diet without carotenoids was used as control. The result showed that the ADC of carotenoids of test diets was higher compared to control. Fish fed astaxanthin diet had higher survival rate (96.67 ± 2.89%), colour measurements of lightness (57.60 ± 7.46%), a*‐values (4.66 ± 1.20), total carotenoids content in skin (33.75 ± 5.02 mg/kg) and muscle (2.16 ± 0.74 mg/kg). Astaxanthin also increased the growth after 14 days (2.00% ± 0.19%/days) but there was no significantly different at the end of experiment. The yellowish‐orange colour performance was more rapidly achieved by fish fed astaxanthin diet after 28 days experimentation. These values suggested that dietary carotenoids were required and astaxanthin diet was superior to other diets for skin pigmentation of Lake Kurumoi rainbowfish.  相似文献   
2.
AbstractThis study examined the performance of mechanically graded timber in bending when exposed to fire at various load ratios. The test specimens were 150 pieces, each with the dimensions of 60 × 120 × 3500mm. The modulus of elasticity (MOE) of 150 specimens was measured, and 60 among them were selected to formulate the prediction equation for MOE and modulus of rupture (MOR), which was used to predict the remaining 90 specimens. These were tested under fire exposure in bending using three-point loading at 11.1%, 16.7%, 33.3%, 66.7%, and 83.3% of the ultimate load. Using mechanically graded timber, which means acknowledging the actual strength of the bending member, permits fairly precise application to the targeted design load. This research confirmed that mechanically graded timber under fire exposure has the following tendencies: under the same load ratio, time to failure is independent of strength class, and, at any load ratio, the critical strength is dependent on the timber strength class. The obtained design bending strength under fire exposure using the reduced cross section method and the reduced strength method conformed to those calculated based on Eurocode 5. Following those findings, mechanically graded timber can be applied to obtain the design bending strength when taking into account the fire attack.  相似文献   
3.
Creep under fire of laminated veneer lumber (LVL) joined with metal connectors was studied. The fire-resistant performance of LVL butt joints connected with metal plates protected with graphite phenolic sphere (GPS) sheeting was discussed. The GPS sheeting was overlaid on the joint in different sizes and locations. The joint was exposed to a burner with a top flame temperature of 800°C and loaded with a load of 200 N to test for creep under fire. The results showed that the fire-resistant performance of the joint was markedly improved by the sheeting. The size and location of the GPS sheet significantly affected the time to rupture of the specimen, which was six times longer than that without GPS. Temperature measurements at the joint showed that the GPS sheeting distributed the heat along the surface and delayed failure. Thermographic images and analyses clarified the improvement in fire-resistant properties due to GPS.  相似文献   
4.
This study focused on the relationship between stress level and the fire resistance of structural lumber. The 210 samples were prepared from 15-year-old trees of Acacia mangium from the Forest Estate Plantation, Indonesia. Specimens were 20 ® × 20 (T) × 500mm (L) and were air-dried. Sixty samples were tested under four-point bending stress to obtain the modulus of elasticity (MOE) and the modulus of rupture (MOR) for classifying the stress grades of the remaining 150 samples. The tests were performed using a four-point load bending position at various stress level while the specimens were exposed to fire along the shear-free region. Time to failure was affected by the stress levels in an exponential trend. Despite changes in stress level, charring rate, and time to failure, the critical stress of a member from the same species was similar. The fire performance under applied load could be predicted by using simplified fire-testing methods. The developed testing apparatus is valid for evaluating the small-scale fire resistant behavior of structural lumber in bending.  相似文献   
5.
6.
This study aimed to investigate the effects of process extrusion on the characteristics of Sargassum cristaefolium sodium alginate (SCSA) extracted using twin-screw extruder. Box-Behnken Design (BBD) from response surface methodology (RSM) was established to understand the effects of temperature, screw speed, and pH on the multiple-responses of alginate characteristics including intrinsic viscosity, yield, and molecular weight. The results revealed that temperature, screw speed, and pH significantly affected (P < .05) all responses. The optimum extraction condition was found at temperature of 58.18°C, screw speed of 77.99 rpm, and pH 10.11. At this condition, the response of residence time distribution was 7.07 ± 0.029 min, yield of 34.01 ± 0.12%, intrinsic viscosity of 460.13 ± 14.75 mL/g, and molecular weight of 217.94 ± 7.14 × 103 g/mol. This alginate had mannuronic acid to guluronic acid (M/G) ratio of 0.28, and the L-guluronic acid block was 0.78, which was higher than the D-mannuronic acid block. Rheological characterization of SCSA in aqueous solution was shear-thinning pseudoplastic, and alginate gel in 1 M CaCl2 was more elastic than liquid.  相似文献   
7.
Preliminary research to understand the flammability of 14 species of shrubs and 8 species of trees based on silica-free ash content was done in order to recognize which shrubs or trees are more flammable. The results show that the silica-free ash content of shrubs and trees leaves was greater than the stems ranging between 1.7% and 11.4% for leaf and 0.4% and 7.8% for the stems. The shrubsDicranopteris linearis, Imperata cylindrica, Eupatorium pubescens, Lantana camara, Eugenia sp.,Cliforia laurifolia, Pterospermum sp.,Hibiscus similis, Clidemia hirta andTrema orientalis must be considered when fire invades the plantation as well as the treeParaserianthes falcataria, Eucalyptus urophylla, Calliandra callothyrsus, andPeronema canescens.  相似文献   
8.
该研究旨在设计一种基于互联网的温室控制系统,以便实现远程监测和控制。所设计的系统包括硬件(传感器、单片机、交换机、电脑、网络摄像头和执行器)和软件(采集和控制)。通过将执行器(风机、泵、喷雾器、机械遮光装置和可旋转摄像头)安装在试验温室并且连接到计算机互联网上对系统性能进行测试。在水培生菜等整个生长期内对其微气候参数进行监测,在3种操作模式(手动、自动和定时)下,对温度、湿度、光照和含水率进行控制。利用开关对风机、泵和喷雾器进行控制以确保微气候参数能保持在所需范围内。机械遮阴和摄头旋转采用伺服电机驱动,由PWM信号驱动进行控制。对3种模式下系统的性能进行评价和比较。结果表明,对温度、湿度、光照和含水率4个参数可以通过互联网Remote Desktop完成远程控制。监控单元提供的植物生长图片可作为制定控制决策的附加信息。  相似文献   
9.
This study determined the indirect selection index of doubled haploid(DH) rice using a multivariate analysis approach to select lines adaptive to salinity stress, comprising three experiments. The first experiment involved the selection of good agronomic characters in a field experiment conducted at an experimental station in Bogor, Indonesia. The second experiment involved salinity tolerance screening through hydroponic cultures using 0 and 120 mmol/L NaCl, conducted at a greenhouse in Bogor. The third experiment involved the validation of the indirect adaptability selection index(IASI) through a field experiment in Sukra(saline area). Field experiments followed a randomized complete block design(RCBD), whereas an RCBD nested factorial design was used for the greenhouse experiment. The first and second experiments used 56 DH lines and four check varieties with three replications. In the second experiment, Pokkali and IR29 varieties were also added as tolerant and sensitive checks of salinity, respectively. The third experiment used 28 selected DH lines, Inpari 29 and one sensitive DH line. The good agronomic index(GAI) was 0.465 yield + 0.433 number of productive tillers + 0.31 number of filled grains. This generated 24 DH rice lines with good agronomic traits. The salinity tolerance index(SaTI) was developed through the average of standardized salinity tolerance score and salinity selection index based on discriminant analysis. This generated 34 DH rice lines with good salinity stress tolerance. The IASI(IASI = GAI – Sa TI) selected 28 DH rice lines adaptive to salinity stress and it was considered effective by Sukra validation.  相似文献   
10.
Peanut is a potent plant to be induced to synthesize bioactive stilbenoids. Bioactivities of those stilbenoids except resveratrol have been meagerly investigated. When peanut kernels (Tainan 14, a Spanish cultivar) were imbibed, incubated 3 days for germination, sliced, incubated with artificial aeration, periodically sampled, lyophilized, extracted with methanol, and subjected to reverse-phase HPLC analysis, four major fractionations were detected and identified as trans-resveratrol (Res), trans-arachidin-1 (Ara-1), trans-arachidin-3 (Ara-3), and trans-isopentadienylresveratrol (IPD). During incubation of the peanut slices, contents of Res, Ara-1, and Ara-3 increased tremendously from initially trace or not detectable amounts up to 147.3, 495.7, and 2414.8 microg/g, corresponding to 20, 16, and 24 h of incubation, while IPD contents continued to increase up to 28 h (4474.4 microg/g). When the four stilbenoids and butylated hydroxytoluene (BHT) were subjected to antioxidant characterization by various measures, all have exhibited varied potencies of antioxidant activity. In particular, retardation of absorbance increase at 234 nm as formation of the conjugated diene hydroperoxides in a real pork oil system stored at 60 degrees C, supplement of Ara-1 at 100 microM has shown equivalent or even greater activity than did BHT. When the media were supplemented with Res, Ara-1, Ara-3, and IPD at 15 microM for cultivation of mouse macrophage RAW 264.7 cells activated by lipopolysaccharide (LPS), the LPS-induced extracellular production of prostaglandin E2 (PGE2) and nitric oxide (NO) was significantly inhibited by Ara-1 (p < 0.001), Res (p < 0.001), Ara-3 (p < 0.01), and IPD (p < 0.01). It is noteworthy and of merit that all test stilbenoids have exhibited potent antioxidant and anti-inflammatory activities and varied as affected by number of hydroxyl groups and isopentenyl or isopentadienyl moiety. Keywords: Arachis hypogaea L.; peanut; groundnut; resveratrol; stilbenoids; arachidin; antioxidant; anti-inflammation.  相似文献   
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