平滑支持向量机聚类研究

支持向量聚类(Support Vector Clustering,SVC)的运算有较高的计算复杂性,本文在优化过程中引入惩罚函数,以此作为目标函数的惩罚项,并用一个平滑函数来近似正号函数,并将优化问题的不等式约束消去,得到一个无约束问题。再利用BFGS-Armijo算法来求解该无约束问题。理论和仿真结果表明该方法提高优化问题的求解效率

The Cloning and Analysis of trapd Full-length cDNA Derived from Oncorhynchus mykiss

易位子相关蛋白δ(TrAnSlOCOn ASSOCIATEd PrOTEIn dElTA,TrAPd)是作为内质网膜蛋白参与细胞内信号序列识别、新生肽链的修饰、转运通道的形成等过程。以虹鳟鱼(OnCOrHynCHuS MykISS)为研究材料,采用rT-PCr和rACE法分离和克隆虹鳟鱼TrAPd基因CdnA的全长序列(gEnbAnk登录号:fJ591154),序列全长949 bP,其中5’端非翻译区(uTr)长109 bP,3’端非翻译区(uTr)长336 bP,开放性阅读框(Orf)长504 bP,编码167个氨基酸,存在1个跨膜区。虹鳟TrAPd蛋白序列与斑马鱼、黑青斑河豚、大西洋鲑、斑点叉尾鮰、热带爪蟾、人和小鼠等脊椎动物的同源性均在80%左右,表明TrAPd基因在进化过程中是高度保守的。Translocon-associated-protein delta(TRAPD) plays a crucial role in physiological processes such as the recognition of signal sequence,the modification of nascent peptide and the formaction of translocation channels.RT-PCR and RACE(Rapid Amplification of cDNA Ends) methods were used for the isolation of the whole cDNA of trapd gene(GenBank accession number: FJ591154) from rainbow trout.Sequence analysis revealed a 949 bp cDNA containing the 109 bp 5'-UTR,336bp 3'-UTR and 504 bp ORF encoding 167 amino acids with a transmembrane region.The sequence alignment between rainbow trout and zebrafish,fugu,salmon,catfish,frog,human and mouse exhibited about 80% identity rate of amino acid.The result indicated the trapd gene is highly conservative in the progress of evolution.河北省科技厅资助项目(0624240011

The Cloning and Analysis of NDK-1 cDNA Derived from Rainbow Trout(Oncorhynchus mykiss)

以虹鳟鱼(OnCOrHynCHuS MykISS)为研究材料,使用rT-PCr和rACE法分离和克隆了虹鳟鱼ndk-1基因CdnA的全长序列(gEnbAnk登录号:(fJ607868)。序列全长953 bP,其中5′端非翻译区(5-′uTr)长45 bP,3′端非翻译区(3′-uTr)长284 bP,开放性阅读框(Orf)长624 bP,编码207个氨基酸。虹鳟鱼ndPk蛋白序列与几种脊椎动物台湾樱花钩吻鲑、斑马鱼、西方爪蟾、非洲爪蟾、人和黑青斑河的同源性分别为95%,72%,68%,68%,65%和64%,表明ndk-1基因在进化过程中是高度保守的。RT-PCR and RACE(Rapid Amplification of cDNA Ends)methods were used for the isolation of the full-length cDNA of NDK-1 gene(GenBank accession number:FJ591154)from rainbow trout.Sequence analysis revealed a 953 bp cDNA containing the 45 bp 5′-UTR,284 bp 3′-UTR and 624 bp ORF encoding 207 amino acids.Sequence alignment of NDPK amino acid between rainbow trout and salmon,zebrafish,western frog,africa frog,human and fugu exhibited 95%,72%,68%,68%,65% and 64% identity rate,respectively.The result indicated the NDK-1 gene was highly conservative in the progress of evolution.河北省科技厅科技计划项目资助(0624240011

激光增进的半导体异质结外延生长

文章阐述了光辅助外延生长的基本原理，光辐射增强生长速率主要

Synthesis of CeO_2 and Co_3O_4 Nanoparticles

[中文文摘]用甲酸代替水作反应介质,以六水合硝酸亚铈为原料,采用非水溶剂水热法制备纳米CeO2;以六水合硝酸亚钴为原料,碳酸铵为沉淀剂,采用均相沉淀法在不同反应条件下,合成纳米Co3O4.用XRD,TEM,BET等手段测定产品的形貌和纳米尺度.实验表明,所合成的CeO2,Co3O4,粒径大小分别在10～20nm和20～30nm范围.该材料作为镍氢电池负极添加剂,大大改良电池的低温放电性能,增加可充电次数.[英文文摘]Nano-scale CeO_2 and Co_3O_4 particles were synthesized by using hydrothermal technique and homogeneous precipitation method. The microstructure and morphology of the nano-scale CeO_2 and Co_3O_4 were investigated by means of XRD, TEM and BET. The results show that their particles are about 10～20 nm and 20～30 nm, respectively, in diameter.国家自然科学基金(20273053,20023001,29933040); 福建省自然科学基金(E0310001)资助

Ge_xSi_(1-x)材料生长的改善

利用超高真空化学气相淀积(UHV/CVD)系统在650℃生长出表面光亮的GeSi单晶。在1200L/min分子泵与前级机械泵间串接450L/min分子泵，改善了生长环境。串接分子泵后生长的样品的X射线双晶衍射分析表明，外延层衍射峰半宽仅为198arcsec，且出现了Pendellosung干涉条纹，说明外延层结晶质量很好

弛豫SiGe衬底上SiGe/Si Ⅱ型量子阱

采用UHV/CVD系统，在Si衬底上生长了具有渐变Si_(1-x)Ge_x缓冲层结构的弛豫Si_(0.76)Ge_(0.24)虚衬底和5个周期的Si_(0.76)Ge_(0.24)/Si多量子阱。在渐变Si_(1-x)Ge_x缓冲层生长过程中引入原位退火，消除了残余应力，抑制了后续生长的SiGe中的位错成核。透射电子显微照片显示，位错被有效地限制在组份渐变缓冲层内，而SiGe上层和SiGe/Si量子阱是无位错的。在样品的PL谱中，观察到跃迁能量为0.961eV的Ⅱ型量子阱的无声子参与(NP)发光峰。由于Ⅱ型量子阱中电子和空穴不在空间同一位置，较高光功率激发下引起的高浓度载流子导致能带弯曲严重。NP峰随激发功率增加向高能方向移动，在一定激发条件下，电子跃迁或隧穿至弛豫SiGe层弯曲的导带底后与处于同一位置的空穴复合发光，所以NP峰积分强度随光激发功率先增加后减小

Cloning and Analysis of ant2 Full-Length cDNA Derived from Rainbow Trout(Oncorhynchus mykiss)

腺苷酸转移酶(AnT)是位于线粒体内膜上参与能量分子传导的转运蛋白,在细胞凋亡调控网络中发挥重要作用.以虹鳟鱼(OnCOrHynCHuS MykISS)为研究材料,使用rT-PCr和rACE法分离和克隆了虹鳟鱼AnT2基因CdnA的全长序列(gEnbAnk登录号:fJ591153).该序列全长1 276 bP,其中5′端非翻译区长66 bP,3′端非翻译区长316 bP,开放性阅读框长894 bP,编码297个氨基酸.该蛋白具有3个保守的线粒体穿膜功能结构域和3个转膜区.通过与其他脊椎动物腺苷酸转移酶蛋白序列的比较,发现该基因具有高度保守性,氨基酸序列的同源性均在90%左右.同源模建显示其与牛的线粒体AdP/ATP载体,CHAIn A蛋白有相同的孔洞(CAVITy)结构.The adenine nucleotide translocase(ANT) family of proteins are the most abundant inner membrane proteins of the mitochondrion.They are responsible for the transport of adenine nucleotides across the inner mitochondrial membrane,importing ADP for oxidative phosphorylation and exporting ATP to the cytosol.In this paper,RT-PCR and rapid amplification of cDNA ends(RACE) methods were used for the isolation of the whole cDNA of ant2 gene(GenBank accession number: FJ591153) from rainbow trout Oncorhynchus mykiss.Sequence analysis reveals a 1 276 bp cDNA containing 66 bp 5′-UTR,316 bp 3′-UTR and 894 bp ORF encoding 297 amino acids.It also has three conserved domains of mitochondrial carrier proteins and three transmembrane helixes.ANT2 shows extensive similarities to the known ADP/ATP translocase polypeptides,and the similarity is about 90% between vertebrates.Homology modeling shows that rainbow trout ANT2 protein has the same cavity structure with the ADP/ATP carrier,chain A of cattle.河北省科技厅科技计划项目(0624240011