187 research outputs found
Study on Flicker Automatic Adjustment for LCD Manufacture
液晶面板(LiquidCrystalDisplay简称LCD)的闪烁(Flicker)不仅会影响其品质,也会对人眼产生很大的危害。因此,每一台液晶显示器出厂前都需要严格的调校。随着技术的进步,闪烁的调校逐渐从模拟到数字化、从手动调校到视觉自动检测的转变。 Flicker调节是通过调整液晶分子偏转的参考电压(Vcom电压),消除正负周期电压差异造成的亮度不均,进而消除画面闪烁现象。自动Flicker调节是通过光电探测器(Sensor)检测LCD亮度值,利用逐级演算法找到最佳值,然后利用信号产生器的I2C通道写入到LCD的EEProm中,达到精确调整Vcom消除画面闪烁的目的。 本文设计并制备...Flicker means “shine unsteadily, moving back and forth very rapidly”. The Flicker of a LCD (Liquid Crystal Display) seriously impacts both the quality of itself and the health of one who watch it. industry, it indicates a defect of pattern blinking, when the pattern is actually invariant. The causation of this defect is the AC signal, which connects to liquid crystal to control the LCD’s brightne...学位:工程硕士院系专业:物理与机电工程学院_工程硕士(电子与通信工程)学号:X201018101
Influence of N, P additions on the transfer of nickel along the food-chain
【中文摘要】 采用放射性同位素示踪法,研究氮或磷添加对镍在东海原甲藻(Prorocentrum donghaienseLu)和中肋骨条藻(Skeletonema costatum)胞内累积的影响;并将其分别投喂中华哲水蚤(Calanus sinicus)后,探讨镍在桡足类体内的吸收和生理周转。结果表明,经过24h暴露后,氮或磷显著影响这两种藻类对镍的吸收,且高浓度氮或磷均能促进镍在这两种藻类细胞内的累积,因而促进镍在中华哲水蚤体内的吸收;而镍在中华哲水蚤体内的生理周转率却不受氮或磷浓度的影响,似乎更受动物个体的生理状态影响;中华哲水蚤对镍的吸收率与藻类细胞内镍含量呈极显著相关(p<0.001),证明了"桡足类只吸收饵料细胞内的水相金属库"的假说。由此可见,近海富营养化可促进浮游植物对镍的吸收,进而影响该金属在浮游生物食物链上的传递。
【英文摘要】 We examined the influence of macronutrient (nitrate or phosphate) additions on the bioaccumulation of Ni in two species of phytoplankton (Prorocentrum donghaiense Lu and Skeletonema costatum), and its subsequent assimilation and physiological turnover in marine copepod (Calanus sinicus) after ingestion, using a radioactive-tracer method. The results showed that N or P addition significantly influenced intracellular Ni accumulation in the algal cells after 24 h of exposure, with higher ambient N or P enhanci...国家自然科学基金委员会与香港研究资助局联合科研资助基金(40131160735);国家自然科学基金资助项目(40576065
Genetic diversity of two wild Penaeus monodon broodstock populations
采用rAPd和MTdnA16SrrnA基因序列分析方法对海南和马来西亚斑节对虾(PEnAEuS MOnOdOn)种群进行了遗传多样性和遗传分化研究。结果表明:15个rAPd随机引物共检测到82个位点,海南和马来西亚种群的多态位点比例分别为75.90%和76.83%,杂合度分别为0.199和0.218,遗传多样性指数分别为0.276和0.288,种群间的遗传距离为0.015;16SrrnA基因检测的种内遗传变异较低,马来西亚和海南种群的核苷酸多样性分别为0.011和0,种群之间的遗传距离为0.008;马来西亚种群比海南种群的遗传变异水平要高得多,且海南种群可能起源于马来西亚种群;进行遗传选育时可考虑引进马来西亚亲虾作为奠基群体。By using RAPD and mtDNA 16S rRNA gene sequence analysis,this paper studied the genetic diversity and differentiation of two Penaeus monodon wild broodstock populations collected from Hainan and Malaysia.Using 15 random primers,a total of 82 RAPD loci were detected.For the Hainan and Malaysia populations,the proportion of polymorphic loci was 75.90% and 76.83%,heterozygosity was 0.199 and 0.218,and genetic diversity index was 0.276 and 0.288,respectively,and the genetic distance between the two populations was 0.015.The genetic variation revealed by 16S rRNA gene sequence analysis was low.The nucleotide diversity of the Hainan and Malaysia populations was 0.011 and 0,respectively,and the genetic distance between the two populations was 0.008.Phylogeographic pattern analysis indicated that Malaysia population had a higher genetic diversity than Hainan population,and the Hainan population could be derived from Malaysia population.Therefore,the broodstock imported from Malaysia could be used as the founder in genetic breeding programs.国家自然科学基金项目(30471322);湖南省教育厅资助科研项目(08B024)资
斑节对虾的遗传育种研究
斑节对虾(Penaeus monodon)俗称草虾,是世界三大养殖虾类之一。广泛分布于印度洋和西太平洋,也是我国本土优质对虾资源之一,但尚未形成遗传稳定的养殖品系,养殖种苗除少数来自海捕外,绝大多数通过人工繁殖获得。供人工繁殖的亲虾主要来自两方面:一是捕捞野生怀卵虾,二是通过摘除眼柄和人工诱导野生雌虾性成熟和产卵,但二者均依赖野生资源。斑节对虾养殖的迅速发展对野生资源造成了极大的压力,过度开发势必引起种质的退化;同时,长期依赖野生亲体培育苗种产生了一些弊端,如亲体携带病毒,养殖对象生长减慢,抗病力下降等。因此,为保护野生资源和阻止野生虾类遗传多样性的丧失,尽快形成遗传稳定的养殖品系显得尤为迫切
考虑谐波谐振和电压稳定的海上风电场无功优化配置方法
海上风电经长距离高压交流海底电缆接入电网,海底电缆容升效应显著,容易引起工频过电压,同时电力电子器件和线路电容引起的谐波谐振问题也严重影响着电网电能质量,因此进行海上风电场无功配置时应充分考虑过电压和谐波谐振问题。针对上述问题,建立了海上风电场谐波模型,对海上风电场的谐波模态阻抗进行扫描,继而分析海上风电场的谐振特性;然后研究了海上风电场无功特性,计算各种发电出力水平和并网点电压下的风电场无功缺额;接着以降低综合成本为目标,以静态电压稳定裕度、最小补偿容量、谐波谐振及过电压为约束,进行海上风电场无功优化配置;最后通过Matlab/Simulink仿真验证所提方法的有效性
Genetic diversity of two wild populations of Penaeus semisulcatus revealed by RAPD technique
【中文摘要】 利用RAPD标记技术检测了厦门和汕头沿海2个短沟对虾群体基因组DNA的多态性,并对其遗传多样性进行了分析。从40条随机引物中筛选出13个10bp引物,共扩增出65条清晰可重复的DNA片段,片断长度为100~2200 bp,在2个群体间没有检测到特异的片段。厦门和汕头群体的多态片段比例分别为87.69%和89.23%,杂合度分别为0.212和0.218,遗传多样性指数分别为0.2847和0.2913,两群体间的遗传距离为0.018,FST值为0.004。可见两野生群体种质资源仍然维持在良好水平,遗传分化程度很低,可能是同一种群,具有进一步开发的潜力。
【英文摘要】 The green tiger prawn,Penaeus semisulcatus is one of the biggest penaeid prawns and widely distributed in tropical and subtropical regions of the Indian Ocean and the West Pacific Ocean.The important economic shrimp species in the north of the South China Sea are Penaeus semisulcatus,Penaeus monodon,Marsupenaeus japonicus and Fenneropenaeus penicillatus.Although the disease-resistance of Penaeus semisulcatus is more effective than that of Penaeus monodon,Litopenaeus vannamei and Fenneropenaeus chinensis,the...国家自然科学基金资助项目(30471322
绢丝昆虫线粒体DNA多态性研究
采用差速离心法和碱变性法制备家蚕、野桑蚕、蓖麻蚕、柞蚕和天蚕蛹线粒体dnA(MTdnA),并进行了限制性酶切片段多态性(rflP)检测。结果表明,绢丝昆虫在种间MTdnA酶切类型差异明显,而在种内不同品种之间则没有差异或差异甚少。在HAEⅢ酶解作用下,家蚕的15个一化和二化性品种的酶切类型相同,5个多化性品种的酶切类型也相同,但它们彼此间则有差异,前者与野桑蚕属同一个类型。由此提示,在家蚕品种演化过程中,一化和二化品种可能与野桑蚕有更密切的亲缘关系
外商直接投资、财政政策波动与地区金融生态环境
本文研究中国外商直接投资、财政政策波动对地区金融生态环境的影响。实证研究表明:外商直接投资与地区金融生态环境的改善存在非线性关系,外商直接投资一方面通过引进先进金融资源推动竞争促进金融生态环境改善,另一方面外商直接投资的不合理使用又会挤占内资企业金融资源,造成内资外逃和资产价格波动;财政政策波动会抑制外商直接投资对改善金融生态环境的溢出效应。国家社科基金青年项目“金融生态环境与技术创新空间集聚效应的机制研究与对策建议”的阶段性成果(15CJL052);;教育部哲学社会科学研究重大课题攻关项目(13JZD010);教育部人文社会科学重点研究基地重大项目(16JJD790036)的资助;;国家留学基金(201706315059)的资
Gene Expression and Activities Analysis of a New Fusion Protein (RGD)3/tTF
为了发展一种新型的融合蛋白(RGD)3/tTF用于肿瘤血管的选择性栓塞治疗,利用PCR技术重组(RGD)3/tTF融合基因,克隆于pET22b(+)载体,表达于E.coliBL21(DE3)。用镍柱纯化融合蛋白。凝血实验与FⅩ活化实验检测融合蛋白tTF组分的活性。间接ELISA分析(RGD)3/tTF与αvβ3的特异结合能力。pET22b(+)/(RGD)3/tTF重组质粒成功获得并表达于E.coliBL21(DE3)。纯化蛋白(RGD)3/tTF能有效诱发血液凝固,活化FⅩ。(RGD)3/tTF与αvβ3的特异结合能力比RGD/tTF提高了32%。新型融合蛋白(RGD)3/tTF已在E.coli系统成功表达,表达蛋白保持tTF的活性并显示比RGD/tTF更高的与αvβ3的结合能力。
【英文摘要】 To develop a new fusion protein (RGD)3/tTF for the therapy of the selective thrombosis of tumor blood vessels. The fused gene (RGD)3/tTF was reconstructed by PCR, was cloned into vector pET22 b(+),and expressed in E.coli BL21(DE_3). The fusion protein was purified through Nickel-affinity chromatography column. The tTF activity of the fusion protein was detected by clotting assay and FⅩ activation assay. The specific binding of (RGD)3/tTF to α_vβ_3 was analyzed by indirect ELISA. The recombinant plasmid pET2...福建省自然科学基金(No.C0410004);; 厦门大学科技创新基金资助(No.XDKJCX20053026)。~
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