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排序方式: 共有298条查询结果,搜索用时 31 毫秒
101.
RF收发器设计 RF收发器的框图示于图2。系统的要求如下: 1.频带902~928MHz,低功率(<0dBm)传输,直接变换FM。 2.数据率 57.6kbits/S,全双工。 3.数据译码/编码-AMI。 4峰值频偏-80kHz。 5.RF带宽-330kHz。 6.信道数-5。 7.信道间隔-500kHz。 8.接收器第-IF频率-73.7MHz。 9.接收器第二 IF频率-10.7MHz。 10.基准频率一11.2MHz, ± 10ppm,100kHz内部频率。 11.收发信道δ-21.9MHz。 12.系… 相似文献
102.
Henock W. Michael Geremew Bultosa Lalit M. Pant 《International Journal of Food Science & Technology》2011,46(4):732-738
The effects of wheat and bean straw growing substrates on nutrient contents of three edible oyster mushrooms and sensory properties of two mushroom foods were investigated. Moisture (fresh weight basis), crude protein, fat, fibre, ash, total carbohydrate, Fe, P and Zn (db) were ranged: 85.18–88.86%, 30.04–37.63%, 1.61–2.55%, 9.33–13.29%, 6.83–9.38%, 29.68–32.53%, 4.86–5.66 mg per 100 g, 12.39–15.36 g kg?1 and 54.61–65.98 mg kg?1, respectively. Moisture, fat and fibre were significantly (P < 0.01) affected by substrates, species and their interactions. Substrates showed no differences on ash, Fe and P (P > 0.05). Protein content was high for mushrooms grown on bean straw. Pleurotus sajor‐caju grown on bean straw had high protein, ash, Fe and P contents. No significant (P > 0.05) sensory acceptability differences were observed for boiled mushroom and mushroom sauce except colour of boiled mushrooms. In Ethiopia, if mushroom consumption is popularised, the support for food nutrition security is substantial. 相似文献
103.
104.
Dual gas diffusion cathode design for microbial fuel cell (MFC): optimizing the suitable mode of operation in terms of bioelectrochemical and bioelectro‐kinetic evaluation
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106.
Microsystem Technologies - Plants provide a defense mechanism against various pathogens or biotic stress through various strategies. Plants respond to fungal invasion by activating defense... 相似文献
107.
Pant D Reynolds LP Luther JS Borowicz PP Stenbak TM Bilski JJ Weigl RM Lopes F Petry K Johnson ML Redmer DA Grazul-Bilska AT 《Reproduction (Cambridge, England)》2005,129(2):191-200
To evaluate the effects of FSH, LH and/or cAMP on expression of connexin 43 (Cx43) in the ovine cumulus-oocyte complex (COC) and gap junctional intercellular communication (GJIC) of cumulus cells, two experiments were carried out. In experiment 1, Cx43 was immunodetected in the COC, before or after maturation, obtained from non-treated or FSH-treated ewes. The expression of Cx43 in the COC was greater (P < 0.01) on day 16 than on day 15 of the estrous cycle. In vivo FSH treatment decreased (P < 0.02) Cx43 expression on day 16 but not on day 15 of the estrous cycle. In experiment 2, intact COCs or isolated cumulus cells obtained from small and large follicles from FSH-treated ewes were cultured with or without FSH, LH or cAMP agonist and evaluated for GJIC by laser cytometry. For large follicles, the basal rate of GJIC was greater (P < 0.01) for cumulus cells in intact COCs than for isolated cumulus cells. FSH increased (P < 0.04) GJIC in cumulus cells in intact COCs and tended to increase (P < 0.1) GJIC in isolated cumulus cells from small follicles but decreased (P < 0.01) GJIC in cumulus cells in intact COCs from large follicles. LH also increased (P < 0.01) GJIC in isolated cumulus cells from small follicles but decreased GJIC in intact COCs (P < 0.01) and isolated cumulus cells (P < 0.02) from large follicles. cAMP increased (P < 0.01) the GJIC in both intact COCs and cumulus cells from small and large follicles. These results indicate that day of estrous cycle, stage of maturation and duration of FSH treatment affect expression of Cx43 in ovine COCs. In intact COCs, GJIC in cumulus cells was enhanced, probably due to the presence of the oocyte. In addition, the effects of FSH and LH, but not cAMP, on GJIC of cumulus cells depended on the stage of follicular development and on the presence of the oocyte. 相似文献
108.
B. S. Mann Vivek Arya B. K. Pant 《Journal of Materials Engineering and Performance》2011,20(6):932-940
The material commonly used in low-pressure high-rating super critical/ultra super critical steam turbines as well as guide
and moving blades of high speed aero compressors is Ti6Al4V alloy. These blades are severely affected owing to erosion which
leads to drop in efficiency and increase in maintenance cost. This article deals with SHS 7170 coating on Ti6Al4V alloy using
twin wire arc spraying (TWAS), enhancing its bonding by providing a thin bond coat and then treating with high-power diode
laser (HPDL). Significant improvement in erosion resistance of this multilayer coating has been achieved because of the formation
of fine-grained micro structure due to rapid heating and cooling rates associated with the laser surface treatment. After
laser surface treatment, the fracture toughness of this multilayer has improved manifold. The water droplet and particulate
erosion test results along with the damage mechanism are reported and discussed in this article. 相似文献
109.
This paper presents a method for analyzing field-replaceable unit (FRU) field-data to obtain accurate field-reliability estimates. The estimates are used to improve reliability prediction and to prioritize the FRU that potentially need design improvement. Application of the method to a large telecommunication project reveals important differences in the age-dependent reliability estimates and the predicted constant estimate. The observed difference is used to measure the statistical bias due to special causes, and a correction term is added to obtain the improved reliability prediction model. The results of applying the priority scheme to FRU data are encouraging and show the importance of including quality-of-information in decision-making 相似文献
110.
Potential internal loading of phosphorus in a wetland constructed in agricultural land 总被引:14,自引:0,他引:14
Wetland construction on agricultural or dairy lands could result in solubilization of phosphorus (P) stored in soils and release to the water column. To study the extent of P flux during the start-up period of a constructed wetland, intact soil-cores from areas used for dairy operations, in Okeechobee, Florida, USA were obtained and flooded with adjacent creek water. In the first 28-day hydraulic-retention period, P concentration in the water column increased several fold due to rapid P flux from impacted soils. A continuous decrease in P flux to the water column until the third hydraulic retention cycle (initial influent P concentration 0.2 mgL(-1)), and constant thereafter suggest that the effect of initial influent P upon long-term P flux from soils could be limited. The initial release maybe due to high concentration of labile P in impacted soils; however, slow dissolution of relatively stable P pools could maintain a steady flux, well above of that observed from non-impacted soils. Water soluble P along with double acid-extractable magnesium explained 76% of the variability in cumulative P flux to the water column. Apparently, co-occurrence of active adsorption-desorption phenomena due to independent maintenance of equilibrium by individual P compounds regulates P dynamics of the water column. The results indicated that equilibrium P concentration of the water column of the wetland would be above 1.3 mgL(-1), which is well above the targeted P level in the water column of the Lake Okeechobee, one of the main water bodies in the area (0.04 mg PL(-1)). This suggests construction of wetlands in agricultural lands could result to substantial internal P loading. However, preventative measures including chemical amendments, establishment of vegetative communities or flushing the initially released P may potentially stabilize the system, and maintain P removal efficiency. 相似文献