Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy resolution.The surface passivation of HPGe has become crucial for achieving an extremely low energy threshold.In this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface passivation.Theoretical calculations of the energy band structure of the -H,-OH,and -NH_(2) passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface state.Based on the theoretical calculation results,the surface passivation layers of the Ge_(2)ON_(2) film were prepared via magnetron sputtering in accordance with the optimum atomic ratio structure.The microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2)ON_(2)/Ge MOS were characterized to test the interface state density.The mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2) eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

负压封闭引流联合保留臀上动脉浅支的臀大肌肌皮瓣修复骶尾部IV期压疮的临床效果

目的:探讨负压封闭引流联合保留臀上动脉浅支的臀大肌旋转肌皮瓣修复骶尾部压疮的临床效果。方法:选取2019年6月—2023年10月温州医科大学附属第一医院收治的12例骶尾部压疮患者,其中男7例,女5例,年龄31~86岁。入院后I期予行负压封闭引流术,4~7 d后行保留臀上动脉浅支的臀大肌肌皮瓣修复创面。观察术后皮瓣成活情况、并发症发生情况,随访观察皮瓣外形、压疮复发情况。结果:本组12例患者,均因长期卧床致骶尾部受压出现IV期压疮,压疮病因:截瘫患者5例,各种原因所致的长期卧床患者7例,其中脑梗死后遗症患者2例,帕金森病患者3例,老年痴呆症患者1例,股骨颈骨折患者1例。病程2周至8年,清创后创面面积为5.0 cm×5.0 cm~10.0 cm×12.0 cm。12例患者术后皮瓣均完全成活,无皮瓣坏死、静脉淤血、创缘开裂等发生。术后随访2~6个月,皮瓣外形较佳、骶尾部软组织饱满、压疮无复发。结论:保留臀上动脉浅支的臀大肌旋转肌皮瓣血运可靠,设计、操作简单,皮瓣可修复面积大,切取不需要离断臀上动脉浅支,供瓣区一般能直接缝合,修复骶尾部压疮效果较佳。

75 GHz germanium waveguide photodetector with 64 Gbps data rates utilizing an inductive-gain-peaking technique

High-performance germanium(Ge)waveguide photodetectors are designed and fabricated utilizing the inductivegain-peaking technique.With the appropriate integrated inductors,the 3-dB bandwidth of photodetectors is significantly improved owing to the inductive-gain-peaking effect without any compromises to the dark current and optical responsivity.Measured 3-dB bandwidth up to 75 GHz is realized and clear open eye diagrams at 64 Gbps are observed.In this work,the relationship between the frequency response and large signal transmission characteristics on the integrated inductors of Ge waveguide photodetectors is investigated,which indicates the high-speed performance of photodetectors using the inductive-gainpeaking technique.

IV型车载储氢瓶聚合物内衬材料的氢气渗透性分析

详细总结论述了气体在高分子聚合物材料中的渗透机理,并简要介绍了有关IV型储氢瓶聚合物内衬氢气渗透性的测试方法以及国内外测试标准。基于此,进一步探讨了测试温度、测试压力以及聚合物材料性能对IV型储氢瓶内衬材料氢气渗透性的影响,并展望了未来的发展方向。

基于MIMIC-IV构建及评估脓毒症患者近期和远期死亡风险预测模型

目的:鉴于脓毒症的高发病率和高病死率,早期识别高风险患者并及时干预至关重要,而现有死亡风险预测模型在操作、适用性和预测长期预后等方面均存在不足。本研究旨在探讨脓毒症患者死亡的危险因素,构建近期和远期死亡风险预测模型。方法:从美国重症监护医学信息数据库IV(Medical Information Mart for Intensive Care-IV,MIMIC-IV)中选取符合脓毒症3.0诊断标准的人群,按7?3的比例随机分为建模组和验证组,分析患者的基线资料。采用单因素Cox回归分析和全子集回归确定脓毒症患者死亡的危险因素并筛选出构建预测模型的变量。分别用时间依赖性曲线下面积(area under the curve,AUC)、校准曲线和决策曲线评估模型的区分度、校准度和临床实用性。结果:共纳入14240例脓毒症患者,28 d和1年病死率分别为21.45%(3054例)和36.50%(5198例)。高龄、女性、高感染相关器官衰竭评分(sepsis-related organ failure assessment,SOFA)、高简明急性生理学评分(simplified acute physiology score II,SAPS II)、心率快、呼吸频率快、脓毒症休克、充血性心力衰竭、慢性阻塞性肺疾病、肝脏疾病、肾脏疾病、糖尿病、恶性肿瘤、高白细胞计数(white blood cell count,WBC)、长凝血酶原时间(prothrombin time,PT)、高血肌酐(serum creatinine,SCr)水平均为脓毒症死亡的危险因素(均P<0.05)。由PT、呼吸频率、体温、合并恶性肿瘤、合并肝脏疾病、脓毒症休克、SAPS II及年龄8个变量构建的模型,其28 d和1年生存的AUC分别为0.717(95%CI 0.710~0.724)和0.716(95%CI 0.707~0.725)。校准曲线和决策曲线表明该模型具有良好的校准度及较好的临床应用价值。结论:基于MIMIC-IV建立的脓毒症患者近期和远期死亡风险预测模型有较好的识别能力,对患者预后风险评估及干预治疗具有一定的临床参考意义。

基于STM32F373的光伏组件IV特性测试系统

为准确方便测量光伏组件的IV特性曲线,设计一款基于STM32F373的光伏组件IV特性测试系统,可测量开路电压、短路电流、IV曲线、PV曲线等。该系统由电流控制单元、信号采集单元、软件处理单元、通信单元、上位机显示单元等组成,采用电子负载电路,以STM32F373单片机DAC输出来调节恒流的电流,同时采集光伏电池的输出电压,对采集到的数据进行卡尔曼滤波和曲线拟合,将电压、电流、功率生成IV、PV曲线显示在TFT彩屏上。该系统还可将数据远程传输到PC端进行数据分析与曲线观察。结果表明,该系统采集曲线准确且速度快,性能良好,采集一次IV曲线的时间仅需1 s,测量的电压电流误差小于1%。该系统体积小便于携带且内部带有锂电池,可充电,可在室外使用。

参苓白术散联合桂枝茯苓丸、达格列净治疗2型糖尿病肾病IV期的蛋白尿的随机对照研究

目的:观察参苓白术散联合桂枝茯苓丸、达格列净治疗2型糖尿病肾病IV期患者蛋白尿的临床疗效。方法:收集于2021年9月~2022年9月潍坊市益都中心医院就诊的诊断为2型糖尿病肾病IV期患者60例。采用随机、对照的临床研究设计分为治疗组和对照组,观察患者症状评分、实验室指标、疾病疗效等指标变化。结果:本研究最终纳入统计分析的治疗组29例、对照组28例。治疗后,治疗组的中医证候、蛋白尿、肾小球滤过率(eGFR)、糖化血红蛋白(HbA1c)、D-二聚体、尿NGAL、低密度脂蛋白疗效优于对照组(P 0.05)。对照组经治后,尿NGAL较治疗前明显下降(P < 0.05),其余指标与治疗前均无差异(P < 0.05)。两组均未见不良反应。结论:参苓白术散联合桂枝茯苓丸、达格列净治疗可减轻DKD IV期患者临床症状,降低蛋白尿、NGAL、糖化血红蛋白、D-二聚体、低密度脂蛋白,保护肾小管及肾小球、改善机体高凝状态及血糖,延缓肾功能下降,提高临床疗效。

18例不可切除IV期胸腺鳞癌的临床特征及预后分析

目的:探讨不可切除IV期胸腺鳞癌的临床特征、治疗方式和预后。方法:收集2018年1月1日至2022年12月31日期间就诊于青岛大学附属医院的18例不可切除IV期胸腺鳞癌患者的临床资料和治疗资料,并随访至2024年2月29日。结果:18例患者中男性12例,女性6例,中位发病年龄60岁;TNM分期IVA期9例,IVB期9例;单纯化疗8例,单纯放疗1例,序贯放化疗4例,同步放化疗2例,化疗联合免疫疗法3例。18例患者总进展率66.7%,中位PFS 27 (19~36)个月。IVA期和IVB期进展率分别为33.3%和100.0% (p = 0.009),中位PFS分别为50 (21~79)和21 (5~37)个月(p = 0.008)。单纯化疗,放化疗和化疗联合免疫疗法进展率分别为75.0%,66.7%,和33.3% (p = 0.793),中位PFS分别为24 (16~32),50 (27~73),和10 (4~16)个月(p = 0.057)。结论:不可切除IV期胸腺鳞癌主要采用以化疗为主的综合治疗,总体预后差,IVA期较IVB期好,化疗联合放疗或免疫疗法较单纯化疗好,建议对非广泛转移阶段的患者行精准治疗。

Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement accuracy.However,the complex and expensive hardware required does not facilitate the application or promotion of this method.Thus,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and device.The electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition events.This relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature identification.To accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the detector.Machine learning is used to input the four shape parameters into the detector.Subsequently,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition events.Some partial-energy deposition events are removed to suppress Compton scattering.The proposed method effectively decreases the MDA of an HPGeγ-energy dispersive spectrometer.Test results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.3%,and 21.6%lower,respectively.

Sensitivity investigation of 100-MeV proton irradiation to SiGe HBT single event effect

The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive position of the Si Ge HBT device is the emitter center, where the protons pass through the larger collector-substrate(CS) junction. Furthermore, in this work the experimental studies are also carried out by using 100-Me V proton. In order to consider the influence of temperature on SEE, both simulation and experiment are conducted at a temperature of 93 K. At a cryogenic temperature, the carrier mobility increases, which leads to higher transient current peaks, but the duration of the current decreases significantly.Notably, at the same proton flux, there is only one single event transient(SET) that occurs at 93 K. Thus, the radiation hard ability of the device increases at cryogenic temperatures. The simulation results are found to be qualitatively consistent with the experimental results of 100-Me V protons. To further evaluate the tolerance of the device, the influence of proton on Si Ge HBT after gamma-ray(^(60)Coγ) irradiation is investigated. As a result, as the cumulative dose increases, the introduction of traps results in a significant reduction in both the peak value and duration of the transient currents.

基于IOE-IV耦合模型的地质灾害易发性评价——以陕西省城固县为例

地质灾害易发性评价是地质灾害排查、风险性调查评价及预警预报工作的基础,其成果可以作为建设工程是否进行地质灾害危险性评估工作的依据。因此,进行区域地质灾害易发性评价研究显得尤为重要。本文以城固县为研究区,以气象水文类、地形地貌类、基础地质类、植被覆盖类共4类12种诱发因素为评价指标。分别采用K-means算法、FCM算法、层次聚类算法、DBSCAN密度算法对区内126处地质灾害样本数据进行分析提纯,剔除13处样本噪声点。利用提纯后的113处样本点建立IOE-IV耦合模型,并对城固县地质灾害易发性进行分区评价,评价结果表明:(1)地质灾害极高—高易发区、中易发区、极低—低易发区的占比分别为92.04%、4.42%与3.54%,预测结果较合理准确;(2)地质灾害发育主要受高程、水系的控制,在高程412~500 m、距水系小于500 m范围内主要为极高—高易发区,地质灾害呈线状发育。研究成果可以为地质灾害易发性评价样本优化、模型选择提供一定的理论依据。

智能IV诊断在分析光伏低效子阵中的应用

由于光伏子阵的非线性行为和其对运行环境的依赖性,传统的保护装置可能无法诊断光伏系统低效子阵问题。为此,业内进行了大量研究来克服这一问题的出现。然而,大多数方法不仅耗时较久,还存在较大的电量损失。同时,由于需要大量数据集,还存在数据过度拟合问题,导致准确率有所欠缺。在本研究中,通过应用华为AI BOOST智能IV诊断3.0,无论是实验评估还是实际应用,相比传统的诊断方法,均取得了较为明显的效果。

基于MIMIC-IV数据库中发生血流感染的危重疾病患者相关数据构建革兰阴性菌血流感染风险预测模型

目的 基于重症医学信息数据库(MIMIC-IV)中发生血流感染的危重疾病患者相关数据构建预测危重疾病患者革兰阴性菌血流感染发生风险预测模型,以期为预测危重疾病患者发生革兰阴性菌血流感染风险提供新的方法。方法 收集MIMIC-IV中2 503例发生血流感染的危重疾病患者的临床资料及实验室检查指标[血常规(红细胞、白细胞、血小板等)、血生化(钾离子、钙离子、氯离子、碳酸氢根、阴离子间隙和尿素氮等)、凝血功能指标(INR、PT、PTT)]数据。将所有危重疾病患者以7∶3的比例分为训练集(1 752例)和验证集(751例)。在训练集中使用LASSO回归初步筛选出危重疾病患者发生革兰阴性菌血流感染的影响因素,并将筛选出来的影响因素行多因素Logistic回归分析,建立危重疾病患者革兰阴性菌血流感染风险预测模型(列线图模型)。在训练集和验证集中通过受试者工作特征曲线(ROC)、校准曲线和决策曲线(DCA)分别对列线图模型的区分度、一致性、临床适用性进行评价。结果 年龄、患有肿瘤、肝胆系统疾病、嗜酒史、钾离子、钙离子、碳酸氢根、阴离子间隙和尿素氮为危重疾病患者发生革兰阴性菌血流感染风险的影响因素,基于以上影响因素采用Logistic回归分析,构建列线图模型。训练集和验证集中,列线图模型预测危重疾病患者发生革兰阴性菌血流感染的ROC下面积分别为0.711(95%CI 0.667~0.756)、0.705(95%CI 0.678~0.733);校准曲线表明列线图模型预测革兰阴性菌血流感染发生的结果与实际结果之间具有良好的一致性(P=0.764);DCA显示列线图模型具有良好的临床适用性。结论 成功构建了预测危重疾病患者发生革兰阴性菌血流感染风险的列线图模型,该模型预测性能较好,能有效识别血流感染高风险危重疾病患者。

基于UPLC-Q-Exactive MS技术的宣白承气汤加味治疗流感病毒与肺炎链球菌共感染小鼠肺炎代谢组学研究

目的基于超高效液相-四级杆-轨道阱高分辨质谱联用(Ultrahigh-performance liquid chromatography-quadrupole exactive mass spectrometry, UPLC-Q-Exactive MS)技术探究宣白承气汤加味对流感病毒/肺炎链球菌(Influenza virus/Streptococcus pneumoniae,Ⅳ/Spn)共感染小鼠肺脏组织中内源性代谢产物的影响,旨在阐明宣白承气汤加味治疗共感染小鼠肺炎的作用机制。方法将36只小鼠随机分为3组,即正常组、模型组和宣白承气汤加味组,每组12只。除正常组外,其余两组小鼠在造模成功6 h后开始灌胃给药,1次/d,连续1周。给药结束后,取小鼠肺脏组织,利用UPLC-Q-Exactive MS技术进行非靶向代谢组学研究,结合主成分分析(Principal component analysis, PCA)和正交偏最小二乘判别分析法(Orthogonal partial least-squares discrimination analysis, OPLS-DA)分析并筛选潜在的代谢产物,并基于R语言对已鉴定的差异性代谢产物进行通路分析。结果在正负离子模式下,共筛选和鉴定出36个潜在的代谢产物,与正常组相比,模型组有27个代谢产物含量显著上升,有9个代谢产物含量显著下降。宣白承气汤加味干预后,36个代谢产物的含量均呈现明显的回调趋势,主要影响亚油酸代谢、烟酸和烟酰胺代谢、核黄素代谢等通路。结论宣白承气汤加味对Ⅳ/Spn共感染小鼠肺炎的治疗作用可能与其调节体内代谢产物失调,恢复体内正常生命活动有关。

司美格鲁肽对2型糖尿病合并多囊卵巢综合征患者血清超敏C反应蛋白及IV型胶原蛋白的影响

目的:探讨司美格鲁肽对2型糖尿病(T2DM)合并多囊卵巢综合征(PCOS)患者血清超敏C反应蛋白(hs-CRP)及IV型胶原蛋白(Col IV)的影响。方法:选取30例初诊T2DM合并PCOS患者为研究对象,给予司美格鲁肽治疗16周。分析比较患者治疗前后血糖、血脂、体重、性激素相关指标及hs-CRP和Col IV的变化,并探究司美格鲁肽治疗后hs-CRP与各指标的相关性。结果:治疗16周后,受试者空腹血糖(FBG)、餐后2 h血糖(2hBG)、糖化血红蛋白(HbA1C)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)、腰围(WC)、体质量指数(BMI)、甘油三酯(TG)、胆固醇(TC)、黄体生成素(LH)、LH/FSH、总睾酮(TT)、hs-CRP、Col IV均较治疗前降低,卵泡刺激素(FSH)较治疗前升高,差异均有统计学意义(P<0.05)。司美格鲁肽治疗后hs-CRP与BMI、WBC、HbA1c、FBG、2hBG、FINS、TG、Col IV正相关(P<0.05)。结论:司美格鲁肽既能改善T2DM合并PCOS患者的血糖、血脂、体重、胰岛素抵抗、性激素,也能改善机体的炎症状态及卵巢纤维化,其可能是T2DM合并PCOS患者的潜在治疗靶点。

基于医院信息系统研究PIVAS自动输液批次决策系统

目的通过静脉输液批次决策的自动化、标准化以及个体化,实现静脉用药调配中心(PIVAS)工作同质化和高效化,进而促进临床安全合理用药。方法根据药物使用的时辰药理学,调查分析人工决策输液批次存在的问题,建立批次时间划分表和制定批次决策规则,基于医院信息系统构建自动输液批次决策系统。由药师维护自动输液批次决策系统,针对该系统的应用效果评价分析。结果应用自动批次决策软件后,PIVAS批次不合格率下降,输液时间合理性提高。审方药师用于决策输液批次的时间减少,大幅度提高PIVAS和病区护士工作效率,同时降低PIVAS输液配送出错频率。结论自动输液批次决策系统构建完成之后,用药时间更合理,提高药物治疗效果;PIVAS工作效率明显提高,工作质量显著提升,输液批次不合格率降低,患者输液批次真正做到编排一致性,提高用药时间合理性,进而使临床用药更合理、更安全,实现个体化治疗。

IV型LPG气瓶紫外线耐老化性能试验方法研究

T/CATSI 02005—2019《液化石油气高密度聚乙烯内胆玻璃纤维全缠绕气瓶》是目前国内唯一一项针对“液化石油气塑料内胆复合气瓶”的团体标准,其中“人工时效试验”是Ⅳ型瓶独有的试验项目,主要测试的是非金属材料的耐老化性能。介绍了紫外线老化试验的研究成果,最终形成了一套耐紫外线老化设备,并验证了设备的可行性。

Study on the Synthesis and in vitro Photodynamic Anti-cancer Activity of Tetra(trifluoroethoxy) Germanium Phthalocyanine

The synthesis and in vitro photodynamic anticancer activity of a new photosen- sitizer, tetra（trifluoroethoxy） germanium phthalocyanine （GePcF）, were studied. GePcF was characterized by UV-Vis, IR, MS and elemental analysis. The in vitro photodynamic activity of GePcF was studied by MTT. IC50 of GePcF for SW480 cells of human colonic adenocarcinoma and HeLa cells of cervical cancer were 36.53 and 45.78 μmol/L, respectively. GePcF as a photosensitizer may be used to treat cancers due to its photodyrmmic anticancer activity.

Study on cosmogenic radioactive production in germanium as a background for future rare event search experiments

Rare event search experiments are one of the most important topics in the field of fundamental physics,and high-purity germanium(HPGe)detectors with an ultralow radioactive background are frequently used for such experiments.However,cosmogenic activation contaminates germanium crystals during transport and storage.In this study,we investigated the movable shielding containers of HPGe crystals using Geant4 and CRY Monte Carlo simulations.The production rates of 68Ge,65Zn,60Co,55Fe,and 3H were obtained individually for different types of cosmic rays.The validity of the simulation was confirmed through a comparison with the available experimental data.Based on this simulation,we found that the interactions induced by neutrons contribute to approximately 90%of the production rate of cosmogenic activation.In addition,by adding an optimized shielding structure,the production rates of cosmogenic radionuclides are reduced by about one order of magnitude.Our results show that it is feasible to use a shielding container to reduce the cosmogenic radioactivity produced during the transport and storage of high-purity germanium on the ground.

Evaluation of the passivation effect and the first-principles calculation on surface termination of germanium detector

The point-contact high-purity germanium detector(HPGe)has the advantages of low background,low energy threshold,and high energy resolution and can be applied in the detection of rare-event physics.However,the performance of HPGe must be further improved to achieve superior energy resolution,low noise,and long-term reliability.In this study,we combine computational simulations and experimental comparisons to deeply understand the passivation mechanism of Ge.The surface passivation effect is calculated and inferred from the band structure and density of interface states,and further con-firmed by the minority carrier lifetime.The first-principles method based on the density functional theory was adopted to systematically study the lattice structure,band structure,and density of state(DOS)of four different systems:Ge–H,Ge–Ge-NH 2,Ge-OH,and Ge-SiO_(x).The electronic char-acteristics of the Ge(100)unit cell with different passi-vation groups and Si/O atomic ratios were compared.This shows that H,N,and O atoms can effectively reduce the surface DOS of the Ge atoms.The passivation effect of the SiO_(x) group varied with increasing O atoms and Si/O atomic ratios.Experimentally,SiO and SiO_(2) passivation films were fabricated by electron beam evaporation on a Ge substrate,and the valence state of Si and resistivity was measured to characterize the film.The minority carrier lifetime of Ge-SiO_(2) is 21.3 ls,which is approximately quadruple that of Ge-SiO.The passivation effect and mechanism are discussed in terms of hopping conduction and surface defect density.This study builds a relationship between the passivation effect and different termination groups,and provides technical support for the potential passivation layer,which can be applied in Ge detectors with ultralow energy thresholds and especially in HPGe for rare-event physics detection experiments in future.