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Since three decades ago it has been established by numerous investigators4,7,9) that the general Process of formation of clay minerals is different between the marine and terrestrial conditions, and that the clays of the marine origin are, in general, of illitic type, whereas those of the terrestrial are of kaolin group. In previous communications,1,2) it was reported that clay fractions of the soil and mud from the Ariake Sea are characterized by the abundance of minerals of illite-montmorin series (montmorin refers to montmorillonite group after Jackson and Sherman8), being different from most terrestrial soils in Kyushu. The matter seems to be of some importance because the Presence of montmorin, even in a relatively small quantity, is likely to exercise a considerable, influence on the behaviour and properties of the clay and the fertility of the soil. The soils of the reclaimed land of the Sea are not only productive, Whether they are clayey or sandy, but also they have been approved to be powerful improving materials for the degraded paddy soils, so-called “Akiochi” soils by several field experiments.  相似文献   
13.
It was reported in a preceding paper7) that the Ando soils from Uemura, Choyo, and Kawanishi contained an unknown mineral colloid which was distinctly different in some respects from coexisting allophane. In the Uemura soil, this clay fraction made up more than 20 per cent of the total clay and more than 6 per cent of the soil7).  相似文献   
14.
The presence of so-valled chlorite-like minerals has been reported in many soils of not only acid but also of alkaline reaction (1). The minerals have been designated by, many terms, for example, dioctahedral vermiculite (2), dioctahedral analogue of vermiculite (3), 14A mineral (4), chlorite-like mineral (5), interstratified chlorite-vermiculite (6), intergradient chlorite-expansible 2:1 layer silicate, intergradient chlorite-vermiculite, intergradient chlorite-vermiculite-montmorillonite, intergrade, or interlayered vermiculite (7), and 2: 1-2: 2 intergrade (1). The minerals designated by these terms are evidently of the same category, and some of them are synonymous. Although they are of intermediate properties, between true chlorite and true vermiculite or montomorillonite, they could be regarded as an independent group of minerals in the course of pedochemical weathering. Jackson (1), for instance, has given the minerals the position of “weathering index 9”, placing them between vermiculite and kaolin as equivalent to montmorillonite, or secondary chlorite and kaolin in his weathering sequence. An explanation of the diagenesis of the minerals has been recently attempted by synthesis of the chlorite-like structures from montmorillonite (8), (9) and vermiculite (10) and mineralogical analyses of soil clay fractions (7).  相似文献   
15.
The study focused on kapok [Ceiba pentandra (L.) Gaertn.] fruit as a biomass for effective utilization. Kapok fruits were harvested just before full maturation at the campus of University of the Philippines Los Banos and in southern Vietnam. The kapok fibers are utilized locally as fiberfill in pillows, quilts, and some soft toys. Kapok fiber was isolated and analyzed microscopically, and the physicochemical properties were determined by spectroscopic methods. Some tests were done to determine the effective utilization of kapok fiber. Microscopic analysis of the higher structure of kapok fiber gave quite different results from cotton fiber, which has a significantly homogeneous hollow tube shape and is composed of cellulose (35 % dry fiber), xylan (22%), and lignin (21.5%). Kapok fiber is characterized by having a high level of acetyl groups (13.0%). Usually cell walls of plants contain about 1%–2% of acetyl groups attached to noncellulosic polysaccharides. Kapok fiber is significantly hydrophobic and does not get wet with water. Thus, the absorptivity of oil was tested. The fiber selectively absorbed significant amounts of oil (40 g/g of fiber) from an oil suspension in freshwater and seawater. It is suggested that this fiber could be used to recover oil spilled in seawater.  相似文献   
16.
六月龄去势公猪表现昏睡、食欲不振、站立困难。尸检发现脾脏边缘呈多重出血灶。从脾脏、肾脏、肌肉和肝脏中分离出革兰氏阳性杆菌,对分离株(TO16177)的16S rDNA基因序列比较分析发现,其可能与未发表过的隐秘杆菌属HJ57-14E菌株(登记号:gi18873551)(比较675bp个碱基,相似性达99.7%)为同一个属。脾脏组织切片的组织学检查发现呈广泛性坏死和炎症,其中革兰氏阳性杆菌显而易见。肝脏中可见多病灶的坏死斑。免疫组织化学检测发现,分离株与抗化脓性隐秘杆菌属(Arcanobacterium pyogenes)和内氏放线菌(Actinomyces naeslundii)的多克隆抗体具有交叉反应,且与后者的交叉反应更强烈。相似的反应也见于扁桃体的化脓灶中分离株,偶尔也见于脾脏和淋巴结中的分离株。本研究结果表明,这种未公开发布的隐秘杆菌属的细菌会引起生长肥育猪多器官功能衰竭,而后继发急性出血性坏死性脾炎。  相似文献   
17.
Trials over two years were conducted using 1389 sweetpotato (Ipomoea batatas L.) genotypes collected from all over the world to characterize the polyphenolic composition in sweetpotato leaves. Wide variation was observed in relation to their total and individual leaf polyphenolic constituents. In all genotypes studied, the total polyphenol contents of sweetpotato leaf ranged from 1.42 to 17.1 g/100 g dry weight. The six different polyphenolic compounds were identified and quantified by NMR, FABMS, and RPHPLC analysis procedures. This is the first report of polyphenolic compositions in sweetpotato leaves. The relative levels of polyphenolic acids in sweetpotato leaves were as follows: 3,5-di-O-caffeoylquinic acid > 4,5-di-O-caffeoylquinic acid > chlorogenic acid (3-O-caffeoylquinic acid) > 3,4-di-O-caffeoylquinic acid > 3,4,5-tri-O-caffeoylquinic acid > caffeic acid. The highest 3,4,5-tri-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid occurred at 221 and 1183.30 mg/100 g dry weight, respectively.  相似文献   
18.
The present study investigated the basal levels and GnRH-induced responses of peripheral testosterone and estrogen in Holstein bulls with poor semen quality. On the basis of semen parameters, bulls (n=5) having poor semen quality were selected as experimental bulls, and good semen quality bulls (n=4) were used as control bulls. Both groups were treated intramuscularly once with GnRH (250 μg of fertirelin acetate). Blood samples were collected at -1 day (d), -30 min and 0 h (treatment) followed by every 30 min for 5 h and 1, 3 and 5 d post-GnRH treatment (PGT), and LH, testosterone and estradiol-17β (E(2)) concentrations were measured. The pretreatment concentrations were used as basal levels. The percentage increments based on the 0-h levels were calculated per bull for each sampling time until 5 h PGT, and differences were compared between the experimental and control groups. The PGT concentrations of testosterone and basal and PGT concentrations of E(2) were significantly lower in the experimental group. The testosterone increment in the experimental group was delayed and significantly lower from 1 to 5 h PGT than those in the control group. It can be suggested that bulls with poor semen quality have delayed and lower GnRH-induced testosterone response and may also have lower estrogen levels.  相似文献   
19.
The anthocyanin composition and antioxidant activity of the crowberry ( Empetrum nigrum) were studied. High-performance liquid chromatography (HPLC) combined with a diode array detector and electrospray ionization mass spectrometry were used for identification and quantification of individual anthocyanins. Freeze-dried crowberry powder was extracted with 80% methanol containing 0.5% acetic acid and subjected to HPLC. Thirteen kinds of anthocyanins were identified. The major anthocyanins were cyanidin-3-galactoside and delphinidin-3-galactoside, at 8.04 and 8.62 mg/g extract, respectively. The HPLC profile of crowberry extract was similar to bilberry and blueberry. The total content of anthocyanins in crowberry was 41.8 mg/g extract, higher than the other nine major berry species (2.5-38.8 mg/g extract). The antioxidant activity was also evaluated using the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis(3-ethybenzothiazoline-6-sulfonic acid) radical quenching assays and the ferric reducing activity power assy. Crowberry extract exerted the strongest antioxidant activity. In conclusion, individual anthocyanins in crowberry were identified and then quantified in this study. Additionally, crowberry is suggested to be associated with a reduction in the risk of developing chronic diseases because of its strong antioxidant activity.  相似文献   
20.
In this study, it was verified whether silicon (Si) affected plant hydraulic resistance, which was one of the significant factors affecting water uptake. Sorghum bicolor (L.) Moench. was grown hydroponically under varying silicon levels and exposed to osmotic stresses. Under osmotic stress, reduction in growth, photosynthesis, and transpiration were alleviated as supplied silicon levels increased. These alleviative effects were ascribed to enhancement of water uptake. Although shoot/root ratio was not affected by silicon, estimated apparent hydraulic resistance was lower in silicon-supplied sorghum than silicon-deficient one under osmotic stress. Simultaneous measurement of transpiration and water uptake rates indicated that under osmotic stress silicon-deficient sorghums showed unbalanced water relation that transpiration rate exceeded water uptake rate, while they were balanced in silicon-supplied sorghums. The results indicated that silicon improved hydraulic resistance, allowing sorghum to avoid from decrease in water uptake rate that happens to silicon-deficient sorghum under water stress.  相似文献   
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