EBAPS(Electron Bombardment Active Pixel Sensor)是一种真空与固体器件结合的混合型光电成像器件,其真空封接需要经过高温烘烤和排气工艺,在研制过程中需要解决CMOS(Complementary Metal Oxide Semiconductor)图像传感器中硅基芯片与...EBAPS(Electron Bombardment Active Pixel Sensor)是一种真空与固体器件结合的混合型光电成像器件,其真空封接需要经过高温烘烤和排气工艺,在研制过程中需要解决CMOS(Complementary Metal Oxide Semiconductor)图像传感器中硅基芯片与陶瓷基座之间粘接用的环氧树脂胶高温分解导致CMOS芯片脱落无法成像的问题。为了解决上述问题,项目组采用三种熔点相近的Au_(88)Ge_(12)、Pb_(92.5)In_(5)Ag_(2.5)以及Zn-Al-Ag-Cu合金焊料焊接经过金属化后的CMOS硅基芯片和陶瓷基座。对上述3种焊料焊接的CMOS图像传感器剖面进行了SEM(Scanning Electron Microscope)和EDS(Energy Dispersive Spectrometer)测试表征,以分析焊接处的性能。结果表明,使用Au_(88)Ge_(12)焊接的CMOS图像传感器可以实现稳定可靠的连接性能。展开更多
以细菌和古菌基因组5′UTR序列作为研究对象,分析在5′UTR的3个不同阅读框架中三联体AUG的分布,发现无论是细菌还是古菌基因组都在阅读框1中有非常明显的AUG缺失(depletion)。AUG的缺失表明在起始密码子上游的AUG很可能会对基因的翻译...以细菌和古菌基因组5′UTR序列作为研究对象,分析在5′UTR的3个不同阅读框架中三联体AUG的分布,发现无论是细菌还是古菌基因组都在阅读框1中有非常明显的AUG缺失(depletion)。AUG的缺失表明在起始密码子上游的AUG很可能会对基因的翻译起始产生影响。分析得知:绝大部分的AUG都是以uORF(upstream open reading frame)的形式出现的,uAUG(upstream AUG)的数量很少,特别是在阅读框1中,而且在细菌基因组的阅读框1中uAUG较多地出现在了含有SD序列的基因上游。比较发现,uAUG引导的序列在同义密码子使用上的偏好性较真正的编码序列差,这可能表明细菌和古菌在同义密码子使用上的偏好性也是决定基因准确地翻译起始的重要因素之一。展开更多
This paper presents a new method of determining Ge in AuGe alloys by potassium iodate(KIO3)potentiometric titration when Ge(Ⅱ)and Au(0)are simultaneously reduced from Ge(Ⅳ)and Au(Ⅲ)by sodium hypophosphite rather th...This paper presents a new method of determining Ge in AuGe alloys by potassium iodate(KIO3)potentiometric titration when Ge(Ⅱ)and Au(0)are simultaneously reduced from Ge(Ⅳ)and Au(Ⅲ)by sodium hypophosphite rather than by distillation separation.The influences of such conditions as the reduction acidity,the dosage of sodium hypophosphite and the reduction time on the determination of Ge were studied.Ge in AuGe alloys such as AuGe_(12),AuGeNi_(12-2),AuAgGe_(18.8-12.5),and AuAgGeNi_(43.8-6-0.2)was measured with the relative standard deviation(RSD)of 0.10%-0.31%and the recoveries of added standard Ge in sample of 99.40%-100.40%under the conditions of 0.40-0.80 mol·L^(-1)HCl,3.3 mol·L^(-1)H^(3)PO^(4),15 g sodium hypophosphite,and reduction time of40 min.The new method presented is of high accuracy in results,good stability and sensibility in end-point,and easy operation and strong selectivity of determination.展开更多
A single mammalian transcript normally encodes one protein, but the transcript of GNAS （G-protein u-subunit） contains two reading frames and produces two structurally unrelated proteins, XLas and ALEX. No other conf...A single mammalian transcript normally encodes one protein, but the transcript of GNAS （G-protein u-subunit） contains two reading frames and produces two structurally unrelated proteins, XLas and ALEX. No other confirmed GNAS-Iike dual-coding transcripts have been reported to date, even though many such candidate genes have been predicted by bioinformatics analysis. In this study, we constructed a series of vectors to test how two protein products were translated from a single transcript in vitro. The length of the ORF （open reading frame）, position of the first AUG and the Kozak motif were found to be important factors. These factors, as well as 55-bp NMD （nonsense-mediated mRNA decay） rule, were used in a bioinformatics search for candidate dual-coding transcripts. A total of 1307, 750 and 474 two-ORF-containing transcripts were found in human, mouse and rat, respectively, of which 170, 89 and 70, respectively, were found to be potential dual-coding transcripts. Most transcripts showed low conservation among species. Interestingly, dual-coding transcripts were significantly enriched for transcripts from the zinc-finger protein family, which are usually DNA-binding proteins involved in regulation of the transcription process.展开更多
文摘EBAPS(Electron Bombardment Active Pixel Sensor)是一种真空与固体器件结合的混合型光电成像器件,其真空封接需要经过高温烘烤和排气工艺,在研制过程中需要解决CMOS(Complementary Metal Oxide Semiconductor)图像传感器中硅基芯片与陶瓷基座之间粘接用的环氧树脂胶高温分解导致CMOS芯片脱落无法成像的问题。为了解决上述问题,项目组采用三种熔点相近的Au_(88)Ge_(12)、Pb_(92.5)In_(5)Ag_(2.5)以及Zn-Al-Ag-Cu合金焊料焊接经过金属化后的CMOS硅基芯片和陶瓷基座。对上述3种焊料焊接的CMOS图像传感器剖面进行了SEM(Scanning Electron Microscope)和EDS(Energy Dispersive Spectrometer)测试表征,以分析焊接处的性能。结果表明,使用Au_(88)Ge_(12)焊接的CMOS图像传感器可以实现稳定可靠的连接性能。
文摘以细菌和古菌基因组5′UTR序列作为研究对象,分析在5′UTR的3个不同阅读框架中三联体AUG的分布,发现无论是细菌还是古菌基因组都在阅读框1中有非常明显的AUG缺失(depletion)。AUG的缺失表明在起始密码子上游的AUG很可能会对基因的翻译起始产生影响。分析得知:绝大部分的AUG都是以uORF(upstream open reading frame)的形式出现的,uAUG(upstream AUG)的数量很少,特别是在阅读框1中,而且在细菌基因组的阅读框1中uAUG较多地出现在了含有SD序列的基因上游。比较发现,uAUG引导的序列在同义密码子使用上的偏好性较真正的编码序列差,这可能表明细菌和古菌在同义密码子使用上的偏好性也是决定基因准确地翻译起始的重要因素之一。
基金the National High Technology Research and Development Program of China (Nos.2012AA063203 and 2012AA063207)。
文摘This paper presents a new method of determining Ge in AuGe alloys by potassium iodate(KIO3)potentiometric titration when Ge(Ⅱ)and Au(0)are simultaneously reduced from Ge(Ⅳ)and Au(Ⅲ)by sodium hypophosphite rather than by distillation separation.The influences of such conditions as the reduction acidity,the dosage of sodium hypophosphite and the reduction time on the determination of Ge were studied.Ge in AuGe alloys such as AuGe_(12),AuGeNi_(12-2),AuAgGe_(18.8-12.5),and AuAgGeNi_(43.8-6-0.2)was measured with the relative standard deviation(RSD)of 0.10%-0.31%and the recoveries of added standard Ge in sample of 99.40%-100.40%under the conditions of 0.40-0.80 mol·L^(-1)HCl,3.3 mol·L^(-1)H^(3)PO^(4),15 g sodium hypophosphite,and reduction time of40 min.The new method presented is of high accuracy in results,good stability and sensibility in end-point,and easy operation and strong selectivity of determination.
文摘A single mammalian transcript normally encodes one protein, but the transcript of GNAS （G-protein u-subunit） contains two reading frames and produces two structurally unrelated proteins, XLas and ALEX. No other confirmed GNAS-Iike dual-coding transcripts have been reported to date, even though many such candidate genes have been predicted by bioinformatics analysis. In this study, we constructed a series of vectors to test how two protein products were translated from a single transcript in vitro. The length of the ORF （open reading frame）, position of the first AUG and the Kozak motif were found to be important factors. These factors, as well as 55-bp NMD （nonsense-mediated mRNA decay） rule, were used in a bioinformatics search for candidate dual-coding transcripts. A total of 1307, 750 and 474 two-ORF-containing transcripts were found in human, mouse and rat, respectively, of which 170, 89 and 70, respectively, were found to be potential dual-coding transcripts. Most transcripts showed low conservation among species. Interestingly, dual-coding transcripts were significantly enriched for transcripts from the zinc-finger protein family, which are usually DNA-binding proteins involved in regulation of the transcription process.
