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排序方式: 共有109条查询结果,搜索用时 15 毫秒
21.
This study was carried out in a natural pasture in Van province of Turkey between the years of 2004 and 2005 to determine the effects of nitrogen and phosphorus fertilization on herbage yield. The study was performed in randomized block with three replications. 0, 4, 8, 16 kg da(-1) nitrogen and 0, 6, 12 kg da(-1) phosphorus applications were examined. The effects of different nitrogen and phosphorus fertilizer applications on plant height, green herbage and crude protein yield were significant for both years. Depending on the increasing nitrogen and phosphorus applications, significant increases were in green herbage, hay and crude protein yields. According to results, differences between 8 and 16 kg da(-1) doses of nitrogen and 6 and 12 kg da(-1) doses of phosphorus applications were insignificant. In the first year, in terms of nitrogen applications, the highest green herbage, hay and crude protein yield (1423.1, 263.3 and 29.2 kg da(-1)) were obtained from 8 kg N da(-1), in the second year, the highest values (1426.1, 602.7 and 67.8 kg da(-1)) were obtained from 16 kg N da(-1) application. As for the phosphorus applications, in the first year, the highest green herbage yield was 1142.2 kg da(-1) at the 6 kg P2O5/da application, hay and crude protein yields (218.2, 23.1 kg da(-1)) were recorded from 12 kg P2O5/da application. In the second year, the highest green herbage, hay and crude protein yields were (1335.8, 549.6 and 66.1 kg da(-1)) determined at the 12 kg P2O5/da application. 相似文献
22.
This study examined possible feasibility of eggplant (Solanum melongena) stalks in the production of particleboard. Three-layer experimental particleboards with density of 0.53, 0.63, 0.73 and 0.78 g/cm3 were manufactured from eggplant stalks using certain ratios of urea formaldehyde (UF) and melamine urea formaldehyde (MUF) adhesives. Modulus of elasticity (MOE), modulus of rupture (MOR), internal bond strength (IB), thickness swelling (TS) properties of the boards were evaluated and a statistical analysis was performed in order to examine possible feasibility of these stalks in commercial particleboard manufacturing. The experimental results have shown that production of general purpose and furniture grade particleboard used in dry conditions using eggplant stalks is technically viable. The results of the study demonstrate that eggplant stalks can be an alternative raw material source for particleboard industry. 相似文献
23.
Muhammad Omer Aijaz Sajjad Haider Fahad S. Al-Mubaddel Rawaiz Khan Adnan Haider Abdulaziz Abdullah Alghyamah Waheed A. Almasry Mohammad Sherjeel Javed Khan Muhammad Javid Wajahat Ur Rehman 《Fibers and Polymers》2017,18(4):611-618
The present study is focused on studying the swelling kinetics, thermal and aqueous stabilities, and determination of various forms of water in the chitosan (CS) and polyacrylonitrile (PAN) blend and semi-interpenetrating polymer network (sIPN). CS/PAN blend hydrogel films were prepared by solution casting technique. The blend film with optimum swelling properties was selected for the synthesis of sIPN. CS in the blend was crosslinked with the vapors of Glutaraldehyde (GTA) to prepare sIPN. The fabricated CS/PAN blend and sIPN hydrogels films were characterized with Fourier transform infrared (FTIR), thermal gravimetric analysis (TGA) and field emission scanning electron microscope (FESEM). The kinetics of swelling, bound and unbound waters and aqueous stability were determined experimentally. FESEM showed good miscibility between CS and PAN, FTIR showed no chemical interaction between CS and PAN; however, it did show a doublet for the sIPN, TGA showed improved thermal stability and swelling kinetic followed second order kinetics. The degree of swelling of the sIPN hydrogels samples at room temperature varied from ~2200 % (with a fair degree of stability (~30 %)) to ~1000 % (with high degree of aqueous stability (43 %)) with increase in the crosslinking time. The calculated unbound water (WUB) max., for the blend was 52.3 % whereas for the bound (WB) the max., was 41.9 %. However, for sIPN hydrogel films, the WUB water decreased (max. 21.0 %) where as the WB increased (max. 52.0 %). The decrease in WUB and increase in the WB is attributed to the formation of a compact structure and increase in the contact area between the water and polymers in sIPN hydrogels due to the induction of new water contacting point in these hydrogel films, respectively. 相似文献
24.
Nagmeldin A.Omer Yun Hu Yan Hu Abdulrahman A.Idriss Halima Abobaker Zhen Hou Haibo Dong Ruqian Zhao 《畜牧与生物技术杂志(英文版)》2018,(2)
Background: Vitellogenin(VTG) is a precursor of egg yolk proteins synthesized within the liver of oviparous vertebrates. Betaine is an important methyl donor that is reported to improve egg production of laying hens with an unclear mechanism. In the present study, we fed betaine-supplemented diet(0.5%) to laying hens for 4 wk and investigated its effect on VTGII expression in the liver.Results: Betaine did not affect chicken weight, but significantly(P 0.05) increased egg laying rate accompanied with a significant(P 0.05) increase in hepatic concentration and plasma level of VTGI. Plasma estrogen level did not change,but the hepatic expression of estrogen receptor α(ERα) mR NA was significantly(P 0.05) up-regulated. Betaine did not affect the protein content of ERα, but significantly(P 0.05) increased hepatic expression of glucocorticoid receptor(GR)at both mR NA and protein levels. Also, ERα/GR interaction tended to be enhanced in the liver nuclear lysates of betainesupplemented hens as determined by co-immunoprecipitation. Furthermore, dietary betaine supplementation significantly increased(P 0.05) the hepatic expression of methyl-transfer enzymes, such as BHMT, GNMT, and DNMT1,which was associated with higher SAM/SAH ratio and hypomethylation of GR promoter regions.Conclusions: Betaine activates hepatic VTGII expression in association with modified DNA methylation of GR gene promoter, GR expression and ERα/GR interaction. Activation of hepatic VTGII expression may contribute, at least partly, to improved egg production in betaine-supplemented hens. 相似文献
25.
Antimicrobial activity of Psidium guajava L 总被引:1,自引:0,他引:1
Psidium guajava aqueous bark and methanolic extracts were found to possess anti-bacterial activity. 相似文献
26.
The fringed tapeworm Thysanosoma actinioides was recovered from the liver of a Najdi camel (Camelus dromedarius) slaughtered in central Saudi Arabia. T. actinioides is recorded for the first time as a parasite of old world camels. 相似文献
27.
28.
An outbreak of cerebrospinal microfilariosis in 23 kids, representing a whole kid crop, occurred on a farm in Qassim, Central Saudi Arabia. The morbidity and mortality rates were 100%. Clinical signs, in kids from the fourth to sixth week of age, manifested as weakness in the hind legs followed by incoordination of movement and feet dragging. Seven to ten days later, the hind legs were completely paralyzed, and within a week the front legs were also paralyzed. The animals continued to feed, drink and suckle normally, and were in good health. Paralyzed kids were helped to suckle by the farm attendants. With time, loss of control of motor functions occurred and the ability to hold the head in upright position was lost, ability to eat or drink was lost. The infected kids health deteriorated and they eventually died. Two dead kids were postmortemed. With the exception of a meningeal haemorrhage seen in one kid, no obvious macroscopic lesions were seen in any of the autopsied animals. Histopathological examination of the spinal cord and brain showed different microfilaria of different sizes between the meninges and the nervous tissue. This indicated that development of the parasite occurred in the nervous tissue. The larger microfilaria contained black deposits, most likely to be digested blood, in their guts. It is likely that the parasites are haematophagus. The main lesions caused by the microfilaria were migratory traumatic haemorrhagic tracts in the spinal cord and the brain. These sometimes contained parts of the microfilariae. In the brain malacic lesions and sporadic aggregates of lymphocytes were also noted. 相似文献
29.
Muhammad Altaf Arain William James Shuttleworth Blake Farnsworth John Adams Omer Lutfi Sen 《Agricultural and Forest Meteorology》2000,100(4)
Micrometeorological variables measured in the BIOSPHERE-2 Center (B2C) enclosed rain forest biome for 1 year were compared with similar measurements made in the Amazon rain forest. In the B2C rain forest, the overlying glass and supporting structure significantly reduces (by approximately a factor of two) the incoming solar radiation. Monthly mean values of above-canopy and within-canopy air temperature, vapor pressure, and vapor pressure deficit are reasonably similar to those of the Amazon rain forest, but there are marked differences in the above-canopy values of these variables in the Arizona summer. Monthly mean diurnal trends also show significant differences. Measurements of vertical air temperature gradient clearly showed two very distinct environments in the 27.4 m high rain forest dome during daylight hours. There is a comparatively cool and fairly well-mixed environment (which is reasonably similar to that found in a natural rain forest) below about 10 m and a hot, thermally stable environment above about 15 m. The nature of the atmospheric turbulence within the B2C rain forest also is significantly different from that normally found in natural rain forests. There is little turbulent mixing above the forest canopy in this enclosed environment. These findings are important for guiding the operation and use of this experimental rain forest facility in future research and for understanding how the rain forest biome functions in an enclosed environment. 相似文献
30.