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排序方式: 共有74条查询结果,搜索用时 15 毫秒
1.
文章介绍了以STC12C5201AD为核心的可燃气体检测与报警装置设计.该装置用催化型可燃气体传感器将气体浓度转换为对应的电压值,然后采用A/D进行采集和标度变换,最后由单片机进行信息处理,判断浓度是否超标,并控制报警动作.  相似文献   
2.
The aim of this study was to develop a novel oil-in-water (O/W) emulsion as adjuvant diluents (AD) for live vaccine against classical swine fever (CSF) that could effectively enhance the immune effect of vaccine.The AD was prepared by high-pressure homogenization technique.Formulations and preparation parameters were optimized with response surface design.Its stability, particle size, polydispersity (PDI) and Zeta potential were characterized.The humoral immune response and cellular immune response of the AD were evaluated with BALB/c mice by intramuscular injection.The particle size of the AD prepared by optimized formulation and parameters was 100.4 nm, PDI was 0.147, and Zeta potential was —28.7 mV.The experiment results showed that the AD had good stability.The AD was inoculated combined with live vaccine against CSF into BALB/c mice by intramuscular injection.The results showed that the live vaccine against CSF specific immune responses could be evoked in mice by co-inoculation with AD and vaccine.The cellular immune response levels in co-inoculated groups were significantly higher than control group (P<0.05), with obvious phenomena of higher levels of IFN-γ, IL-6 and IL-4 in serum.The result revealed that cellular immune capability significantly improved with the AD.The results strongly revealed that cellular immune capability significantly improved by introducing AD for effective immune-adjuvant for live vaccine against CSF.  相似文献   
3.
We isolated two pseudorabies virus (PRV) isolates (designated OT-1 and OT-2) from two hunting dogs exhibiting neurological manifestations after eating the flesh of wild boar hunted in Oita prefecture, Kyushu Island, Japan. The isolates corresponded to a previously reported PRV (MY-1 strain) isolated from a hunting dog in neighboring Miyazaki prefecture, and it clustered into genotype II based on the glycoprotein C sequence. Our results suggest that this common PRV strain may have been maintained in wild boars on Kyushu Island even though domestic pigs in this area have attained an Aujeszky’s disease-free status.  相似文献   
4.
文章阐述了一种自来水电子压力表的设计装置,具有压力系数大小实时现实、存储、查询、报警等功能。该系统采用高精度的传感器来检测压力,低温漂的仪表放大器AD620对数据进行放大,通过8位AD转换器件ADC0808进行AD采集和数据变换处理,并可将数值通过串口发送到电脑,实现压力系数的数字化测量。  相似文献   
5.
以10个热带、温带玉米群体为材料,采用混合线性(AD)模型和MINQUE(1)法,对7个产量相关性状的遗传力、遗传方差分量比率、群体加性和显性遗传效应进行分析。结果表明:试验群体对籽粒产量的贡献为加性效应>显性效应,产量相关性状狭义遗传力为穗粗>百粒重>穗粒重>穗长>籽行数>行粒数>秃尖;加性效应最好的2个群体是豫综5号和墨黄1号;显性效应最强的4个组合为墨白962×豫综5号、新墨1号×WBM-C4、墨黄1号×SUWAN-1和墨白962×EP7;综合来看,豫综5号和墨黄1号是最具利用潜势的群体种质。  相似文献   
6.
为了获得高效稳定的阿特拉津基因,分离出更多的阿特拉津降解菌,试验采用PCR基因扩增和氮源利用方法,对AD3菌株的阿特拉津降解基因进行了检测和测序,并与其他菌株阿特拉津降解基因的序列进行了比较。结果表明:Micrococcus luteus AD3菌株含有阿特拉津降解基因trzN,atzB,atzC和atzDEF。其中trzN基因中心区的序列与Arthrobacter sp.TC1的trzN完全相同,atzB和atzC基因中心区的序列与Pseudomonas sp.ADP的atzB和atzC完全相同。AD3菌株能以氰脲酸为唯一氮源生长,Micrococcus luteus AD3菌株能将阿特拉津彻底降解成CO2和NH3。  相似文献   
7.
AD7793芯片采用四线制、多通道切换设计,较好地满足了地温测量中高精度温度测量、多通道测量的要求。介绍了该芯片在地温测量中的应用,并分析了其在测量中容易产生的误差,通过硬件优化和软件设计等方法进行了改进,最终测试结果表明,系统具备较好的测量精度和可重复性。  相似文献   
8.
Peng F  Tao Q  Wu X  Dou H  Spencer S  Mang C  Xu L  Sun L  Zhao Y  Li H  Zeng S  Liu G  Hao X 《Fitoterapia》2012,83(3):568-585
Twenty-nine phenolic compounds were isolated from the root bark of fresh (Yunnan) ginger and their structures fully characterized. Selected compounds were divided into structural categories and twelve compounds subjected to in-vitro assays including DPPH radical scavenging, xanthine-oxidase inhibition, monoamine oxidase inhibition, rat-brain homogenate lipid peroxidation, and rat pheochromocytoma PC12 cell and primary liver cell viability to determine their antioxidant and cytoprotective properties. Isolated compounds were also tested against nine human tumor cell lines to characterize anticancer potency. Several diarylheptanoids and epoxidic diarylheptanoids were effective DPPH radical scavengers and moderately effective at inhibiting xanthine oxidase. An enone–dione analog of 6-shogaol (compound 2) was isolated and identified to be most effective at protecting PC12 cells from H2O2-induced damage. Almost all tested compounds inhibited lipid peroxidation. Three compounds, 6-shogaol, 10-gingerol and an enone-diarylheptanoid analog of curcumin (compound 6) were identified to be cytotoxic in cell lines tested, with KB and HL60 cells most susceptible to 6-shogaol and the curcumin analog with IC50 < 10 μM. QSAR analysis revealed cytotoxicity was related to compound lipophilicity and chemical reactivity. In conclusion, we observed distinct compounds in fresh ginger to have biological activities relevant in diseases associated with reactive oxygen species.  相似文献   
9.
存储时间对玉米秸秆理化性状及产甲烷潜力的影响   总被引:1,自引:1,他引:0  
收割后的秸秆需要经过时间不等的存储后进入到厌氧系统生产沼气,而秸秆的存储时间不同对产甲烷潜力有一定的影响。该文对收割后的玉米秸秆分别经过0、2、5、10、20、30和45 d自然堆放存储,分析不同存储时间秸秆的理化性质变化以及对产甲烷潜力的影响。通过分析不同存储时间秸秆的感官性状、总固体(totalsolid,TS)、挥发性固体(volatile solid,VS)、pH值、木质纤维素、叶绿素、挥发性脂肪酸(volatile fat acid,VFA)等理化性质,发现秸秆存储20 d后各个性状趋于稳定。对不同存储时间处理的秸秆进行产甲烷潜力(biochemical methane potential,BMP)测试,结果显示,存储0、2、5、10、20、30、45 d的BMP分别为325.49、315.35、297.85、296.71、295.25、287.83、291.01 mL/g(以VS计)),随着存储时间的增加,BMP总体上呈下降趋势,且存储0~5 d的下降较快,存储大于5 d的秸秆BMP结果相近。试验得出,秸秆存储时间不同对产甲烷潜力有明显影响,主要由于受到多种原料性质的影响,尤其是木质纤维素、可溶性化学需氧量、还原糖、挥发性脂肪酸。研究结果可为工程化秸秆沼气项目和生物天然气项目的运行提供参考。  相似文献   
10.
介绍了高精度16位模,数转换器AD7705在一种溶解氧检测仪中的应用,AD7705同单片机的接口、内部寄存器结构及其配置和使用方法,并给出了在C51语言基础上的设计与编程,并附C源程序,有较强的参考性。  相似文献   
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