p-on-n型10μm像元间距长波1280×1024红外探测器制备研究

采用p-on-n结构的碲镉汞红外探测器芯片的暗电流低、少子寿命长,是目前高性能红外探测器的主流发展方向。为了满足未来红外探测器小型化的发展需求,开展了p-on-n型10μm像元间距长波1280×1024探测器芯片研究。针对As离子注入激活、长波小间距芯片制备技术的难点,开展了As离子注入技术、As激活退火技术的研究分析。通过不同的表征方法验证了最佳条件,并通过器件工艺进行了探测器芯片的制备。测试其I-V特性曲线,获得了性能较好的探测器芯片。该研究对小像元间距p-on-n型长波碲镉汞焦平面器件的制备具有重要意义。

低能N^(+)注入诱变耐诺氟沙星的金黄色葡萄球菌及其机制分析

利用低能N^(+)注入诱变筛选耐诺氟沙星的金黄色葡萄球菌,通过基因组测序、耐药表型和生物被膜分析,探索低能N^(+)注入驱动金黄色葡萄球菌产生诺氟沙星耐药性的机制。结果表明,利用低能N^(+)注入诱变获得81株耐诺氟沙星的金黄色葡萄球菌,其中44株耐药菌16S rRNA或耐药基因出现片段缺失、插入、点突变和拷贝数变化;且基因变化高的耐药菌的药物外排蛋白、生物被膜的生物量和密度显著增加,对诺氟沙星的耐药性提高了8~16倍,并对5~8种抗菌药物产生了多重耐药。说明低能N^(+)注入可能通过介导金黄色葡萄球菌16S rRNA或相关耐药基因变异,调控细菌药物外排蛋白表达量增加和生物被膜形成能力增强,进而介导菌株产生耐药性。

低能N^(+)注入诱导大肠杆菌的16S rRNA遗传进化

为了探究低能N^(+)注入对大肠杆菌16S rRNA遗传进化与耐药表征的作用,本研究利用低能N^(+)注入诱变筛选耐药大肠杆菌,通过基因组de novo测序获得其16S rRNA基因序列,通过K-B法检测诱变菌株的耐药特征。结果共诱变获得了25株耐药菌株,其中5株诱变菌16S rRNA基因分别出现片段缺失,点突变(A257C),GC%含量增高,二级结构变异,并获得多药耐药特性。结果提示:低能N^(+)注入可以驱动大肠杆菌16S rRNA基因的随机突变和进化,进而调节耐药基因从头合成或变异,使大肠杆菌耐药性改变。

磁过滤电弧离子镀TiN与N离子注入性能研究

目的研究磁过滤电弧离子镀TiN与N离子注入对金属基体的保护效果。方法采用磁过滤电弧离子镀和离子注入在不锈钢表面分别制备了TiN薄膜与N注入改性层,以及二者的复合膜层。对薄膜的相结构、微观形貌进行了表征,对薄膜进行了极化曲线测试,同时在半球样品表面制备涂层并进行盐雾测试。结果所制备的TiN涂层为(111)晶面择优取向,离子注N预处理后沉积的TiN薄膜,仍保持(111)面的择优取向;电化学测试结果显示,TiN和N离子注入能够使不锈钢基体自腐蚀电位分别提高0.64、0.25 V,TiN薄膜具有最低的维钝电流密度4.9×10^(-6) A/cm^(2),N离子注入+TiN复合薄膜的维钝电流密度与N离子注入样品接近;盐雾试验结果表明,TiN以及N离子注入+TiN复合薄膜样品能够保证铜半球在12h的中性盐雾试验中无明显腐蚀痕迹。结论N离子注入预处理对MFAIPTiN涂层耐蚀性能的提升效果有限,单一的MFAIP TiN涂层便可应用于复杂形状的工程材料表面镀膜,可以增强其抗腐蚀能力,延长使用寿命。

Synthesis of Poly[(3-octanoylpyrrole-2,5-diyl)-p-(N,N-dimethylamino)benzylidene] and Its Properties by Nitrogen Ion Implantation

A novel soluble π-conjugated polymer, poly[(3-octanoylpyrrole-2,5-diyl)-p-(N,N-dimethylamino)benzylidene](POPDMABE), was synthesized firstly by the condensation of 3-octanoylpyrrole with para-dimethylaminobenzaldehyde. The chemical structure of the polymer was characterized by FTIR and 1H NMR spectrometries. The polymer is a potential nonlinear optical(NLO) material. According to the function of optical forbidden band gap(E_g) and photon energy(hν), the optical forbidden band gaps of the polymer before and after ion implantation were calculated. The resonant third-order nonlinear optical properties of POPDMABE before and after ion implantation were also studied by using the degenerate four-wave mixing(DFWM) technique at 532 nm. When the energy is 25 keV and the dose is 2.2×10 17 ions/cm 2, the {polymer′s} optical forbidden band gap is about 1.63 eV which is smaller than that of the non-implanted sample(1.98 eV) and the resonant third-order NLO susceptibility of POPDMABE is about 4.3×10 -7 esu, 1 order of magnitude higher than that of the non-implanted sample(4.1×10 -8 esu). The results show that nitrogen ion implantation is an effective method to improve the resonant third-order NLO property of the polymer.

A Preliminary Study on DNA Mutation Induction of Maize Pollen Implanted by Low Energy N^+ Beam

The maize pollens were implanted with seven different doses of 30 keV N+ beam respectively, The genomic DNA polymorphism from treated pollens were analyzed with 104 primers by using RAPD respectively. The results showed that N^+ beam-induced mutation of maize pollens can result in the change of their DNA bases. The mutation is not properly random and its frequency increases with a rise in 30 keV N+ beam doses. It is conformed with A-G transformation, which is one of the most important factors in DNA bases induced by N+ beam.

RAPD analysis of alfalfa DNA mutation via N^+ implantation

Germination capacity of alfalfa seeds under low energy N+ implantation manifests oscillations goingdown with dose strength. From analyzing alfalfa genome DNA under low energy N+ implantation by RAPD (RandomAmplified Polymorphous DNA), it is recommended that 30 polymorphic DNA fragments be amplified with 8 primersin total 100 primers, and fluorescence intensity of the identical DNA fragments amplified by RAPD is different be-tween CK and treatments. Number of different polymorphic DNA fragments between treatment and CK via N+ im-plantation manifests going up with dose strength.

Influence of Target Temperature on Cemented Carbides for Dual Ion Implantation

A Cemented Carbide material was implanted with dual nitrogen plus tantalum ions at temperatures of 100℃ and 400℃ and a dose of 8× 10^17 ions cm^-2. The thickness of the implanted layers increased by about an order of magnitude when the temperature was elevated from 100℃ to 400℃. Higher surface hardness was also obtained in the high temperature implantation. X-ray diffraction showed the presence of nitrides of tantalum and tungsten in the implanted surface.

益肾通癃汤对前列腺癌模型裸鼠N-cadherin、Vimentin蛋白表达的影响

目的:探究益肾通癃汤对前列腺癌(PCa)皮下种植瘤模型裸鼠N-钙黏蛋白(N-cadherin)、波形蛋白(Vimentin)表达的影响。方法:用前列腺癌PC-3细胞悬液建立PCa皮下种植瘤模型裸鼠,造模成功后将其随机分为模型组、益肾通癃汤低剂量组、益肾通癃汤中剂量组、益肾通癃汤高剂量组,每组10只。各给药组灌胃给予相应药物,模型组灌胃给予等体积生理盐水,2次/d,连续3周。给药结束后,观察裸鼠一般状态,测量体质量及瘤体大小,称重并计算抑瘤率;运用HE染色观察各组裸鼠种植瘤病理学改变;ELISA法检测各组裸鼠血清中N-cadherin、Vimentin的水平;Western blotting检测各组裸鼠种植瘤组织中N-cadherin、Vimentin蛋白表达情况;PCR检测各组裸鼠种植瘤组织中N-cadherin m RNA、Vimentin m RNA表达情况。结果:与模型组比较,益肾通癃汤低、中、高剂量组裸鼠状态均可,瘤体质量,血清中N-cadherin、Vimentin水平,种植瘤组织中N-cadherin、Vimentin的蛋白及m RNA相对表达量均降低(P<0.05),瘤体细胞少量坏死;与益肾通癃汤低剂量组比较,益肾通癃汤中、高剂量组裸鼠一般状态可,瘤体质量,血清中N-cadherin、Vimentin水平、种植瘤组织中N-cadherin、Vimentin蛋白及mRNA相对表达量均降低(P<0.05),瘤体细胞部分坏死;与益肾通癃汤中剂量组比较,益肾通癃汤高剂量组裸鼠一般状态良好,瘤体质量,血清中N-cadherin水平,种植瘤组织中N-cadherin、Vimentin蛋白相对表达量,种植瘤组织中Vimentin mRNA相对表达量均降低(P<0.05),瘤体细胞坏死多;益肾通癃汤高剂量组裸鼠血清中Vimentin水平、种植瘤组织中N-cadherin mRNA相对表达量与益肾通癃汤中剂量组比较,差异无统计学意义(P>0.05);益肾通癃汤低、中、高剂量组裸鼠抑瘤率分别为26.67%、42.45%、66.26%。结论:益肾通癃汤对人前列腺癌PC-3细胞皮下种植瘤模型裸鼠N-cadherin、Vimentin蛋白的表达具有一定的抑制作用,其机制可能与抑制肿瘤上皮间质转化(EMT)过程相关。

低能N^(+)注入诱导金黄色葡萄球菌的耐药与16S rRNA遗传进化研究

为了研究低能N^(+)注入诱导金黄色葡萄球菌对其进化的影响,通过低能N^(+)注入诱变获得耐药突变株,利用基因组De novo测序分析其16S rRNA基因的突变与耐药性变化,探索低能N^(+)注入驱动金黄色葡萄球菌16S rRNA遗传进化与耐药进化的机制。结果共获得158株耐药的金黄色葡萄球菌,其中11株诱变耐药菌的16SrRNA基因序列分别出现片段缺失,GC%从51.23%改变为50.91%~53.12%,V 1,V 2,V 3和V 6区发生多个点突变,并出现对诺氟沙星、万古霉素、庆大霉素的不同耐药特征。研究证明低能N^(+)注入可以引发金黄色葡萄球菌16S rRNA基因的随机突变及其耐药进化,为分析低能N^(+)离子注入加速16S rRNA变异和耐药基因从头起源提供新的遗传证据。

Fluid simulation of the pulsed bias effect on inductively coupled nitrogen discharges for low-voltage plasma immersion ion implantation

Planar radio frequency inductively coupled plasmas（ICP） are employed for low-voltage ion implantation processes,with capacitive pulse biasing of the substrate for modulation of the ion energy. In this work, a two-dimensional（2D） selfconsistent fluid model has been employed to investigate the influence of the pulsed bias power on the nitrogen plasmas for various bias voltages and pulse frequencies. The results indicate that the plasma density as well as the inductive power density increase significantly when the bias voltage varies from 0 V to-4000 V, due to the heating of the capacitive field caused by the bias power. The N＋fraction increases rapidly to a maximum at the beginning of the power-on time, and then it decreases and reaches the steady state at the end of the glow period. Moreover, it increases with the bias voltage during the power-on time, whereas the N2-＋ fraction exhibits a reverse behavior. When the pulse frequency increases to 25 kHz and40 kHz, the plasma steady state cannot be obtained, and a rapid decrease of the ion density at the substrate surface at the beginning of the glow period is observed.

Electrical and structural properties of diamond films implanted by various doses of oxygen ions

Oxygen-doped diamond films are prepared by implanting various dose oxygen ions into the diamond films synthesized by hot filament chemical vapour deposition, and their electrical and structural properties are investigated. Hall effect measurements show that lower dose oxygen ion implantation is beneficial to preparing n-type diamonds. The carrier concentration increases with the dose increasing, indicating that oxygen ions supply electrons to the diamonds. The results of AES spectrum indicate that oxygen ions are doped into the diamond films, and the O-implanted depth is around 0.1μm. Raman spectrum measurements indicate that the lower dose oxygen ion implantation at 10^14 cm^-2 or 10^15 cm^-2 is favourable for producing less damaged O-doDed diamond films.

Multi-effects and Mechanism of Broad Beau M_1 Root-tip Cells Implanted by Low Energy N^+ Beam

Broad beans were divided into six groups and implanted with N+ beam of 30 KeV, 8 × 1016/cm2 per time for various radiating times respectively. Besides the statistics of its vigor of germination, the M1 root-tip cells of these broad beans were systematically analyzed on their changes in mitotic percentage, morphology and behavior of chromosomes, along with the structure o f cytoskeletons, including microtubule and intermediate filament. Based on all results of these studies, our opinions have been expressed in the report on the mechanism of low-energy N+ beams effecting on higher dicotyledons such as broad beau.

OPTICAL EFFECTS AND MICROSTRUCTURE OF BURIED INSULATOR LAYER FORMED BY O^+ AND N^+ CO-IMPLANTATION

The microstructure and optical properties of a buried layer formed by O+(200keV,1.8×1018/cm2)and N+(180 keV,4×1017/cm2)co-implantation and annealed at 1200℃for 2 h have been investigated by Auger electron,IR absorption and reflection spectroscopicmeasurements.The results show that the buried layer consists of silicon dioxide and SiOx（x【 2）and the nitrogen segregates to the wings of the buried layer where it forms an oxynitride.Bydetail theoretical analysis and computer simulation of the IR reflection interference spectrum,therefractive index profiles of the buried layer were obtained.

Boron implanted emitter for n-type silicon solar cell

The effects of ion doses on the properties of boron implanted Si for n-type solar cell application were investigated with doses ranging from 5×10^14cm^-2 to 2×10^15cm^-2 and a subsequent two-step annealing process in a tube furnace.With the help of the TCAD process simulation tool, knowledge on diffusion kinetics of dopants and damage evolution was obtained by fitting SIMS measured boron profiles. Due to insufficient elimination of the residual damage, the implanted emitter was found to have a higher saturation current density（J0e） and a poorer crystallographic quality. Consistent with this observation, V oc, J sc, and the efficiency of the all-implanted p^＋–n–n^＋solar cells followed a decreasing trend with an increase of the implantation dose. The obtained maximum efficiency was 19.59% at a low dose of 5×10^14cm^-2. The main efficiency loss under high doses came not only from increased recombination of carriers in the space charge region revealed by double-diode parameters of dark I–V curves, but also from the degraded minority carrier diffusion length in the emitter and base evidenced by IQE data. These experimental results indicated that clusters and dislocation loops had appeared at high implantation doses, which acted as effective recombination centers for photogenerated carriers.

Differential Expression of Retrotransposon WIS 2-1A Response to Vacuum, Low-Energy N^+ Implantation and ^(60)Coγ-ray Irradiation in Wheat

Mutagenesis and retrotransposons have a close relationship, but little attention has been paid yet to the activity of retrotransposons produced by physical mutagens. The variation of retrotransposon WIS 2-1A activity in wheat （Triticum aestivum L.） embryos at three different growth times （30 h, 45 h and 60 h） was investigated after they had been treated with N^＋ implantation in a vacuum of 5× 10^-2 Pa and irradiation by ^60Coγ-ray respectively. For each of the three growth times the expression of WIS 2-1A showed almost entirely a same trend of downregulation, upregulation, then downregulation, and upregulation again with the increase in dose of N^＋ implantation, but the expression appeared irregular with the increase in irradiation of ^60Coγ-ray. In conclusion, the acutely activating effect of WIS 2-1A stimulated by vacuum and high dose N^＋ implantation within a shorter incubation time may provide a convenient tool to advance the research on mutagenic breeding and function genes.

Expression of N-acetyl-glucosamine-6-O-sulfotransferase in the endometrium of implantation window stage from infertile patients

Objective:To observe the expression of N-acetyl-glucosamine-6-O-sulfotransferase(GN-6-ST)in the endometrium during the window stage of implantation from infertile women before IVF-ET treatment,we compared the GN-6-ST gene expression level between the women with succeeded and failed implantation,and investigated the roles of selectin and its ligands in the embryo implantation.Methods:The hysteroscopy and endometrial biopsies were performed in patients prior to undergoing IVF-ET treatment in the IVF Center of the First Affiliated Hospital of Nanjing Medical University from July 2004 to March 2005.Fourteen patients who succeeded in implantation were taken as study group,while the 28 infertile patients with failed implantation served as control group.The RT-PCR method was used to detect the mRNA levels of N-acetyl-glucosamine-6-O-sulfotransferase in the endometrium during the window stage of imp-lantation of the women from both groups.Results:For these infertile patients with succeeded implantation,the average mRNA expression level of acetyl-glucosamine-6-O-sulfotransferase in the endometrium during the window stage of implantation was(0.65±0.33),while for those with failed implantation cycle,the average mRNA expression level was(0.41±0.36),which was significantly lower than that of study group,P<0.05.Conclusions:The combination of the selectin and ligands may play a role in the embryo implantation capacibility.

低能N^+辐照提高小麦反转录转座子Wis2-1A的转录并影响其邻近基因表达

为研究小麦反转录转座子Wis2-1A在低能离子束辐照小麦生物效应中的作用,用实时定量PCR的方法测定不同注量下Wis2-1A的转录水平及在基因组中的拷贝,并用转座子显示技术研究了Wis2-1A在注量为5×1017N+/cm2的低能离子束处理后的转录对其邻近基因表达的影响,结果显示:不同注量的N+辐照都能提高Wis2-1A的转录水平,但在基因组水平上的拷贝没有大的提高,且在较高注量下,由于Wis2-1A的高水平转录导致其邻近的某些基因沉默,这说明Wis2-1A在低能离子注入生物效应中起主要作用。

低能N^+注入选育凝结芽孢杆菌高效生防菌株

为了进一步提高凝结芽孢杆菌NJYHHWG 877005菌株的拮抗性能,获得生防效果更好的菌株,利用低能N^+注入菌株进行诱变,并通过平板对峙培养对诱变处理后的菌株进行筛选。结果表明,菌株存活率曲线遵循N^+注入生物效应的马鞍型曲线,根据其存活率及突变率确定N^+最佳注入能量为15 ke V,最佳注入剂量为140×10^(13)个/cm^2。通过筛选获得1株具有良好性状的突变株L1,芽孢形成率达77.42%,对灰葡萄孢霉菌的抑制率高达87.81%,分别较原始出发菌株提高了23.79、11.71个百分点,且连续传代培养8次,遗传稳定性良好。

N^+离子束注入对玉米幼苗生长及POD同工酶的影响

以郑单 95 8和农大 1 0 8及其各自交系为试材 ,研究了离子束注入后对M1 苗期性状及过氧化物同工酶的影响 ,结果表明 :离子束注入后的各处理种子发芽指数、出苗率都低于对照 ,其中徐 1 78和黄C的发芽指数分别只有对照的 60 %和 5 0 % ;出苗率以昌 7- 2下降最多 ,只有对照的 43%。从POD同工酶酶谱看 ,胚、幼芽和苗期叶片 ,均检测出同工酶不同程度、不同形式的改变 。