涡轮机械转子在二氧化碳工质中风摩损耗的数值分析

在超临界二氧化碳布雷顿循环系统设计中，为提高系统能量转换效率，需要准确预测风摩损耗。风摩损耗大小与转子转速，转子几何结构，工质状态密切相关。本文针对2 MPa二氧化碳工质中，高转速（23 000 r/min）转子的风摩损耗特性进行数值计算分析。研究结果表明：转子粗糙高度对超临界二氧化碳布雷顿循环系统中高转速以及可能出现的较高压力工况下的风摩损耗具有显著影响。已有风摩损耗经验关系式未考虑粗糙度的影响，直接使用可能带来较大误差。风摩损耗随着转子粗糙高度的增加而增加，随转子转速的增加而增加，气腔间距的变化对风摩损耗不会造成明显影响。厦门大学能源学院发展基金(2018NYFZ01

基于倾向评分匹配的机器人辅助与胸腹腔镜微创三切口食管癌根治术近期疗效比较

目的探讨机器人辅助微创食管癌切除术（RAMIE）和胸腹腔镜联合微创食管癌切除术（MIE）的安全性与有效性。方法回顾性分析中国科学技术大学第一附属医院胸外科 2021年 4月至 2022年 12月收治的188例接受微创Mckeown食管癌切除术的患者资料。其中RAMIE组69例，男性49例，女性20例，年龄（67.2±7.2）岁；MIE组119例，男性89例，女性30例，年龄（69.1±7.0）岁。采用倾向性评分匹配法（PSM）对两组患者进行1∶1匹配，匹配后 RAMIE组58例，MIE组58例。采用 t检验、Pearson χ2 检验、Fisher’s精确检验等比较两组患者术中情况和术后并发症发生率。结果经过PSM处理后，两组患者基线资料无明显差异。RAMIE组和MIE组在手术时间、术后带管天数、淋巴结清扫总数方面无明显差异（P＜0.05）；在术中出血、左喉返淋巴结清扫数目方面RAMIE组优于MIE组，差异有统计学意义（P＜0.05）；MIE组在淋巴结清扫总站数方面更优（P＜0.05）。在术后并发症方面RAMIE组和MIE组两组数据差异无统计学意义（P＞0.05）结论RAMIE近期疗效与MIE食管癌切除术相当；机器人辅助微创食管癌切除术可以减少术中出血同时在淋巴结清扫中尤其是在喉返神经旁淋巴结清扫中更具优势

闽南地区TT病毒的变异及经输血传播的初步证据

TT virus(TTV)DNA was tested by nested-PCR from sera of hepatitis patients and volunteer blood donors in Minnan area. The amplified segment was a 189 base pair region in TTV ORF2. A total of six sequences were obtained from three non-A to G hepatits patients and two from volunteer blood donors. The sequences were found to be with 82.9% to 99.3% homology to TTV Japanese strain and Chinese strain. The divergence of sequence in these six segments varied from 0.7% to 17.1%, which indicated that the TTV had been existing for a long time in this area. In the serum of a non-A to G hepatitis patient who was negative for TTV DNA in the 14th day of disease course turned to be positive in the 30th day, two TTV sequences were obtained which showed 92.1% nucleotide homology. It indicated that different TTV strains can co exist in the same person. This patient's blood had been transfused ten times between the collection of his TTV negative sample and his positive serum sample. Seven of the blood donors were traced an..

TT病毒在非甲～庚型和重型肝炎中感染的研究

我们根据日本报道的ＴＴ病毒（ＴＴＶ）ＤＮＡ序列［１］，设计合成两对特异性聚合酶链反应（ＰＣＲ）引物，用巢式ＰＣＲ（ｎｅｓｔｅｄＰＣＲ）对非甲～庚型和重型肝炎患者感染ＴＴＶ情况进行研究。对其中１份ＴＴＶＤＮＡ阳性的ＰＣＲ产物进行纯化、克隆、测序，..

Concentration Protile of Etchant Measured by Microelectrode Technique in the Process of Chemical Micromachining

利用微圆盘电极技术,测定了KBr、L-胱氨酸和硫酸组成的刻蚀溶液体系中Pt电极表面电化学氧化产生的刻蚀剂Br2浓度分布,为约束刻蚀剂层技术(CELT)中刻蚀体系的选择和优化提供更直观的依据.GaAs表面CELT微加工实验证明了用微圆盘电极测得的表面刻蚀剂的浓度分布趋势与微加工实验所得到的结果一致.A carbon-disk microelectrode was used to investigate the surface concentration profile of etchant Br2, which was electrogenerated on the Pt working electrode. The steady state reducing currents of Br2 at different distances away from the Pt electode was measured. The concentration profile was estimated from the current-distance variation curves as a function of different sampling times. Experimentally determined concentration profiles are in good agreement with those estimated from the microetching results. The microelectrode technique has offered a good method to choose suitable etching solution for chemical micromachining.国家高新技术发展规划(863项目)(2002AA404170);; 福建省自然科学基金计划资助项目(E0520001

TT病毒与肝炎关系的临床流行病学研究

目的　对闽南地区各种肝炎患者、健康体检者、义务献血员和肝癌患者共480例从临床流行病学角度探讨TT病毒(TTV)的致病性及其与各种肝炎的关系。方法　采用巢式PCR检测血清TTVDNA、ELISA检测血清抗HAVIgM、HBsAg、抗HBcIgM、抗HCVIgG、抗HEVIgG,用EPIINFO60软件进行统计分析。结果　480名研究对象中TTVDNA的总检出率为23.96%。各种肝炎患者的TTV总阳性率为2394%,肝癌患者的TTV阳性率为2069%,而健康者的TTV阳性率为2484%,义务献血员的阳性率为3000%,均未见明显差别。从临床类型看,急性肝炎、慢性肝炎和重症肝炎的TTV阳性率都在25%左右;从病原类型看,非甲～戊型肝炎的TTV阳性率为2619%,并未见与相应健康者的2523%阳性率的差别;除HCV由于感染率太低而无法分析外,HAV、HBV、HEV阳性肝炎患者间TTV的阳性率分别为2000%、2314%、2179%,未见TTV与这些已知肝炎病毒的明显相关。对一个时期内的全部135例住院肝炎患者及153名健康者进行肝炎病原分析,HAV、HBV、HEV在肝炎患者中的阳性率都要明显高于健康人(P=00142),而TTV在肝炎患者中的阳性率与健康人没有明显差别(P=06021);对病毒的单独致病性进行分析,HAV、HBV、HEV在非重叠感染的肝炎患者中的阳性率都要明显高于健康人(P=00037),而TTV在非甲～戊型肝炎患者中的

金属Cu表面三维齿状微图形的复制加工——约束刻蚀剂层技术 (CELT)的应用

主要介绍了一种Cu的CELT加工的化学刻蚀体系和捕捉体系 ,并通过控制刻蚀时间、刻蚀电流、刻蚀剂浓度、捕捉剂浓度等实验参数和优化电化学模板的制作工艺 ,以规整的齿状结构为模板 ,在Cu的表面实现了三维微结构的复制加工 ,得到了与齿状结构模板互补的三维微结构 ,用SEM和AFM对实验结果进行了表征 ,表征结果证明约束刻蚀剂层技术在金属三维加工方面的可行性和潜在优势。金属Cu由于具有优良的导热导电性能以及很好的延展性 ,在微系统 (也称微机电系统 )中应用广泛 ,因此对Cu的刻蚀加工对微系统技术的发展具有重要的意义。约束刻蚀剂层技术 (ConfinedEtch antLayerTechnique简称CELT)作为一种新型的微加工技术[1] ,能够加工复制出复杂三维结构 ,到目前为止 ,该技术已成功应用于Si、GaAs等材料微结构的复制加工[2 ,3]

Concentration protile of etchant measured by microelectrode technique in the process of chemical micromachining

A carbon-disk microelectrode was used to investigate the surface concentration profile of etchant Br-2, which was electrogenerated on the Pt working electrode. The steady state reducing currents of Br-2 at different distances away from the Pt electode was measured. The concentration profile was estimated from the current-distance variation curves as a function of different sampling times. Experimentally determined concentration profiles are in good agreement with those estimated from the microetching results. The microelectrode technique has offered a good method to choose suitable etching solution for chemical micromachining