Surface diffraction beamline at the SSRF

BL02U2 of the Shanghai Synchrotron Radiation Facility is a surface diffraction beamline with a photon flux of 5.5×10^(12) photons/s at 10 keV and a beam size of 160µm×80µm at the sample site.It is dedicated to studying surfaces(solid-vacuum,solid-gas)and interfaces(solid-solid,solid-liquid,and liquid-liquid)in nanoscience,condensed matter,and soft matter systems using various surface scattering techniques over an energy range of 4.8-28 keV with transmission and reflection modes.Moreover,BL02U2 has a high energy resolution,high angular resolution,and low beam divergence,which can provide excellent properties for X-ray diffraction experiments,such as grazing incident X-ray diffraction,X-ray reflectivity,crystal truncation rods,and liquid X-ray scattering.Diversity of in situ environments can also be provided for the samples studied.This paper describes the setup of the new beamline and its applications in various fields.

Radiofrequency ablation for single hepatocellular carcinoma 3 cm or less as first-line treatment

AIM:To evaluate long-term outcomes of radiofrequency(RF) ablation as first-line therapy for single hepatocellular carcinoma(HCC) ≤ 3 cm and to determine survival and prognostic factors.METHODS:We included all 184 patients who underwent RF ablation as a first-line treatment for single HCC ≤ 3 cm between April 2005 and December 2013.According to the criteria of Livraghi,the 184 patients were divided into two groups:those suitable for surgical resection(84 cases) and those unsuitable for surgical resection(100 cases).The primary endpoints were the overall survival(OS) rate and safety;the secondary endpoints were primary technique effectiveness and recurrence rate.RESULTS:There were 19(10.3%) cases of ablation related minor complications.The complete tumor ablation rate after one RF session was 97.8%(180/184).The rate of local tumor progression,extrahepatic metastases and intrahepatic distant recurrence were 4.9%(9/184),9.8%(18/184) and 37.5%(69/184),respectively.In the 184 patients,the 1-,3-,and 5-year OS rates were 99.5%,81.0%,and 62.5%,respectively.The 1-,3-,and 5-year OS rates were 100%,86.9%,and 71.4%,respectively,in those suitable for surgical resection and 99.0%,76.0%,and 55.0%,respectively,in those unsuitable for surgical resection(P = 0.021).On univariate and multivariate analyses,poorer OS was associated with Child-Pugh B class and portal hypertension(P < 0.05).CONCLUSION:RF ablation is a safe and effective treatment for single HCC ≤ 3 cm.The OS rate of patients suitable for surgical resection was similar to those reported in surgical series.

Multi-slice spiral computed tomography in differential diagnosis of gastric stromal tumors and benign gastric polyps,and gastric stromal tumor risk stratification assessment

BACKGROUND The biological characteristics of gastric stromal tumors are complex,and their incidence has increased in recent years.Gastric stromal tumors(GST)have potential malignant tendencies,and the probability of transformation into malignant tumors is as high as 20%-30%.AIM To investigate the value of multi-slice spiral computed tomography(MSCT)in the differential diagnosis of GST and benign gastric polyps,and GST risk stratification assessment.METHODS We included 64 patients with GST(GST group)and 60 with benign gastric polyps(control group),confirmed by pathological examination after surgery in PLA General Hospital,from January 2016 to June 2021.The differences in the MSCT imaging characteristic parameters and enhanced CT values between the two groups before surgery were compared.According to the National Institutes of Health’s standard,GST is divided into low-and high-risk groups for MSCT imaging characteristic parameters and enhanced CT values.RESULTS The incidences of extraluminal growth,blurred boundaries,and ulceration in the GST group were significantly higher than those in the control group(P<0.05).The CT values and enhanced peak CT values in the arterial phase in the CST group were higher than those in the control group(P<0.05).The MSCT differential diagnosis of GST and gastric polyp sensitivity,specificity,misdiagnosis rate,missed diagnosis rate,and areas under the curve(AUCs)were 73.44%,83.33%,26.56%,16.67%,0.784,respectively.The receiver operating characteristic curves were plotted with the arterial CT value and enhanced peak CT value,with a statistical difference.The results showed that the sensitivity,specificity,misdiagnosis rate,missed diagnosis rate,and AUC value of arterial CT in the differential diagnosis of GST and gastric polyps were 80.18%,62.20%,19.82%,37.80%,and 0.710,respectively.The sensitivity,specificity,misdiagnosis rate,missed diagnosis rate,and AUC value of the enhanced peak CT value in the differential diagnosis of GST and gastric polyps were 67.63%,60.40%,32.37%,39.60%,and 0.710,respectively.The incidence of blurred lesion boundaries and ulceration in the high-risk group was significantly higher than that in the low-risk group(P<0.05).The arterial phase and enhanced peak CT values in the high-risk group were significantly higher than those in the low-risk group(P<0.05).CONCLUSION Presurgical MSCT examination has important value in the differential diagnosis of GST and gastric benign polyps and can effectively evaluate the risk grade of GST patients.

Do the existing staging systems for primary liver cancer apply to combined hepatocellular carcinoma-intrahepatic cholangiocarcinoma?

Background:The incidence of combined hepatocellular carcinoma-intrahepatic cholangiocarcinoma(cHCC-ICC)is relatively low,and the knowledge about the prognosis of cHCC-ICC remains obscure.In the study,we aimed to screen existing primary liver cancer staging systems and shed light on the prognosis and risk factors for cHCC-ICC.Methods:We retrospectively reviewed 206 cHCC-ICC patients who received curative surgical resection from April 1999 to March 2017.The correlation of survival measures with the histological types or with tumor staging systems was determined and predictive values of tumor staging systems with cHCC-ICC prognosis were compared.Results:The histological type was not associated with overall survival(OS)(P=0.338)or disease-free survival(DFS)(P=0.843)of patients after curative surgical resection.BCLC,TNM for HCC,and TNM for ICC stages correlated with both OS and DFS in cHCC-ICC(all P<0.05).The predictive values of TNM for HCC and TNM for ICC stages were similar in terms of predicting postoperative OS(P=0.798)and DFS(P=0.191)in cHCC-ICC.TNM for HCC was superior to BCLC for predicting postoperative OS(P=0.022)in cHCC-ICC.Conclusion:The TNM for HCC staging system should be prioritized for clinical applications in predicting cHCC-ICC prognosis.

Validating the accuracy of a multifunctional smartwatch sphygmomanometer to monitor blood pressure

BACKGROUND Hypertension is the most modifiable factor associated with cardiovascular events and complications.The conventional blood pressure(BP) meter method is simple but is limited in terms of real-time monitoring abnormal BP.Therefore,the development of a multifunction smartwatch(HUAWEI WATCH D) sphygmomanometer could significantly improve integrated BP monitoring.METHODS We enrolled 361 subjects from Chinese PL A General Hospital,Beijing,China to validate the accuracy of the smartwatch versatile sphygmomanometer using ISO 81060-2:2018.Resting and ambulatory BP accuracy of the smartwatch were compared with gold standard clinical sphygmomanometers using ISO 81060-2:2018 guidelines,the accuracy of 24 h systolic blood pressure(SBP) circadian rhythm monitoring,and diurnal high SBP alert for this smartwatch were assessed using a confusion matrix approach.Additionally,we analyzed online users of different ages for compliance.RESULTS Eighty-five subjects underwent resting BP measurements;the mean resting BP differences between two devices were-0.683±6.203 mmHg(SBP)(P=0.723) and 1.628±5.028 mmHg(diastolic blood pressure,DBP)(P=0.183).In 35 subjects’ ambulatory BP measurements,the mean differences of ambulatory BP were-1.943±5.475 mmHg(SBP)(P=0.923) and 3.195±5.862 mmHg(DBP)(P=0.065).All data complied with ISO 81060-2:2018 guidelines(mean ≤±5 mmHg and standard deviation ≤±8 mmHg) with no significant differences.Positive predictive values(PPV) of resting SBP and DBP were 0.635 and 0.671,respectively.The PPV of ambulatory SBP and DBP were 0.686.Also,24 h SBP circadian rhythm monitoring was performed in 107 subjects:accuracy=0.850,specificity=0.864,precision/PPV=0.833,sensitivity=0.833,and F1-measure(F1)=0.833.The accuracy,specificity,precision,sensitivity,and F1 values in 85 subjects undergoing diurnal high SBP alerting were 0.858,0.876,0.706,0.809,and 0.754,respectively.CONCLUSIONS When compared with the gold standard clinical sphygmomanometer,smartwatch results were consistent and accurate.Online user feedback showed that elderly individuals cared more about BP monitoring accuracy,with better compliance.

Effects of Total-Ionizing-Dose Irradiation on Single-Event Burnout for Commercial Enhancement-Mode AlGaN/GaN High-Electron Mobility Transistors

We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight degradation of devices caused by gamma rays can affect the stability of the devices during the impact of high energy particles.During heavy ion irradiation,the safe working values of drain voltage are significantly reduced for devices which have already been irradiated by 60Co gamma rays before.This could be attributed to more charges trapped caused by 60Co gamma rays,which make GaN devices more vulnerable to SEB.Moreover,the electrical parameters of GaN devices after 60Co gamma and heavy-ion irradiations are presented,such as the output characteristic curve,effective threshold voltages,and leakage current of drain.These results demonstrate that the synergistic effect of TID on SEB for GaN power devices does in fact exist.

Progressive liver injury and increased mortality risk in COVID-19 patients:A retrospective cohort study in China

BACKGROUND Liver injury is common and also can be fatal,particularly in severe or critical patients with coronavirus disease 2019(COVID-19).AIM To conduct an in-depth investigation into the risk factors for liver injury and into the effective measures to prevent subsequent mortality risk.METHODS A retrospective cohort study was performed on 440 consecutive patients with relatively severe COVID-19 between January 28 and March 9,2020 at Tongji Hospital,Wuhan,China.Data on clinical features,laboratory parameters,medications,and prognosis were collected.RESULTS COVID-19-associated liver injury more frequently occurred in patients aged≥65 years,female patients,or those with other comorbidities,decreased lymphocyte count,or elevated D-dimer or serum ferritin(P<0.05).The disease severity of COVID-19 was an independent risk factor for liver injury(severe patients:Odds ratio[OR]=2.86,95%confidence interval[CI]:1.78-4.59;critical patients:OR=13.44,95%CI:7.21-25.97).The elevated levels of on-admission aspartate aminotransferase and total bilirubin indicated an increased mortality risk(P<0.001).Using intravenous nutrition or antibiotics increased the risk of COVID-19-associated liver injury.Hepatoprotective drugs tended to be of assistance to treat the liver injury and improve the prognosis of patients with COVID-19-associated liver injury.CONCLUSION More intensive monitoring of aspartate aminotransferase or total bilirubin is recommended for COVID-19 patients,especially patients aged≥65 years,female patients,or those with other comorbidities.Drug hepatotoxicity of antibiotics and intravenous nutrition should be alert for COVID-19 patients.

Magnetic resonance imaging features of minimal-fat angiomyolipoma and causes of preoperative misdiagnosis

BACKGROUND Minimal-fat angiomyolipoma(mf-AML)is often misdiagnosed as renal cell carcinoma before surgery.AIM To analyze the magnetic resonance imaging(MRI)features of mf-AML and the causes of misdiagnosis by MRI before operation.METHODS A retrospective analysis was performed on ten patients with mf-AML confirmed by surgical pathology,all of whom underwent preoperative MRI examination to analyze the morphological characteristics and MRI signals of the tumor.RESULTS MRI revealed a circular-like mass in 4/10(40%)patients,an oval mass in 6/10 patients(60%),a mass with a capsule in 9/10 patients(90%),and a mass with a lipid component in 7/10 patients(70%).The diameter of the masses in all ten patients was from 11 to 47 mm;the diameter was between 11 mm and 40 mm in 8/10(80%)patients and between 40 mm and 47 mm in 2/10(20%)patients.CONCLUSION An oval morphological characteristic is strong evidence for the diagnosis of mf-AML,while a capsule and lipids are atypical manifestations of mf-AML.

Preoperative neutrophil-to-lymphocyte ratio predicts symptomatic anastomotic leakage in elderly colon cancer patients: Multicenter propensity score-matched analysis

BACKGROUND The neutrophil-to-lymphocyte ratio(NLR),a composite inflammatory biomarker,is associated with the prognosis in patients with colorectal tumors.However,whether the NLR can be used as a predictor of symptomatic postoperative ana-stomotic leakage(AL)in elderly patients with colon cancer is unclear.AIM To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon cancer.METHODS Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively analyzed.Receiver operating characteristic curve analysis was performed to determine the best predictive cutoff value for the NLR.Twenty-two covariates were matched using a 1:1 propensity score matching method,and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative AL.RESULTS Of the 577 patients included,36(6.2%)had symptomatic AL.The optimal cutoff value of the NLR for predicting AL was 2.66.After propensity score matching,the incidence of AL was significantly greater in the≥2.66 NLR subgroup than in the<2.66 NLR subgroup(11.5%vs 2.5%;P=0.012).Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoper-atively,preoperative albumin concentration,preoperative prognostic nutritional index,and preoperative NLR and AL occurrence(P<0.05);multivariate logistic regression analysis revealed that an NLR≥2.66[odds ratio(OR)=5.51;95%confidence interval(CI):1.50-20.26;P=0.010]and blood transfusion intraoperatively and within 2 d postoperatively(OR=2.52;95%CI:0.88-7.25;P=0.049)were risk factors for the occurrence of symptomatic AL.CONCLUSION A preoperative NLR≥2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly patients with colon cancer.The preoperative NLR has predictive value for postoperative symptomatic AL after elective surgery in elderly patients with colon cancer.

乌鲁木齐市中小学生近视与眼部生物学参数调查分析

目的:调查研究乌鲁木齐市中小学生近视与眼部生物学参数差异。方法:横断面调查。于2021-09/11采取立意抽样的方法选取乌鲁木齐市4所学校7~18岁中小学生2 495人进行相关眼部检查。比较不同年龄段、性别、民族学生眼部生物学参数和屈光状态的差异,并分析纳入学生等效球镜度(SE)与眼部生物学参数的相关性。结果:纳入学生视力不良检出率为80.36%,近视检出率为55.91%,散光检出率为42.96%,其中低度近视检出率为63.80%,中度近视检出率为27.60%,高度近视检出率为8.60%。不同年龄、民族学生视力不良、近视及散光检出率、SE及部分眼部生物学参数均有差异(均P<0.05),其中维吾尔族、哈萨克族学生视力不良、近视及散光检出率明显低于汉族学生。男生视力不良、近视检出率均低于女生,散光检出率高于女生。Spearman相关分析显示,眼轴长度、轴向长度与轴率比、前房深度、瞳孔直径与SE呈负相关(r_(s)=-0.664、-0.724、-0.320、-0.086,均P<0.001);晶状体厚度与SE呈正相关(r_(s)=0.147,P<0.001)。结论:乌鲁木齐市中小学生近视患病率较高,不同年龄、民族儿童青少年眼球生物学参数存在差异性。

新疆叶城县6~18岁中小学生屈光状态筛查及近视戴镜率分析

目的:调查研究新疆叶城县6~18岁中小学生的屈光状态及近视戴镜率情况。方法:横断面调查。于2021-10/2022-06采用以学校为单位的分层随机抽样法选取新疆喀什地区叶城县51所小学和30所中学学生81863人纳入研究,收集学生的基本资料,并进行非睫状肌麻痹验光,检测裸眼远视力和戴镜矫正视力,观察不同年龄、性别及民族学生的屈光状态、近视戴镜率和足矫率情况。结果:纳入学生近视检出率为13.39%(10958/81863),戴镜率为23.96%(2626/10958),足矫率为50.57%(1328/2626)。随着年龄的增长近视检出率呈一定的上升趋势,且女生近视检出率大于男生(15.75%vs 10.96%),汉族、维吾尔族、其他民族学生近视检出率分别为68.12%、12.63%、22.42%。结论:新疆叶城县6~18岁中心学生筛查性近视检出率及戴镜率均较低,而汉族学生近视检出率及戴镜率明显较维吾尔族及其他民族学生高。

新疆和田地区居民干眼现况调查与分析

目的:评估中国新疆和田地区居民干眼的患病率和潜在的相关危险因素。方法:2019-01/09在中国新疆和田地区采取立意抽样的方法选取105个村18~98岁居民共计6 027人作为受试者,并进行横断面研究。调查者采用眼表疾病指数(OSDI)问卷的方式收集干眼主观症状,检查荧光素染色泪膜破裂时间(FBUT)及泪液分泌试验(SchirmerⅠ试验)来收集客观体征,从而分析干眼患病率及其危险因素。结果:从中国新疆和田地区居民中招募18~98岁共6 339名受试者进行相关眼部检查和问卷调查,其中有效问卷6 027份,有效回收率为95.08%。6 027名受试者中干眼检出率为40.37%(2 433/6 027),其中男性、女性干眼检出率分别为36.47%(846/2 320)、42.81%(1 587/3 707);18~24岁、25~34岁、35~44岁、45~54岁、55~64岁、≥65岁干眼检出率分别为13.77%、15.67%、33.31%、46.35%、47.65%、53.50%。根据干眼严重程度分为轻度干眼、中度干眼及重度干眼,它们的构成比依次为80.11%、19.03%、0.86%。结论:干眼在研究人群中的患病率为40.37%,女性干眼患病率高于男性,且随年龄的增加干眼患病率呈上升趋势,高龄和女性是干眼的危险因素。

Laparoscopic vs computerized tomography-guided radiofrequency ablation for large hepatic hemangiomas abutting the diaphragm

AIM: To compare safety and therapeutic efficacy of laparoscopic radiofrequency(RF) ablation vs computed tomography(CT)-guided RF ablation for large hepatic hemangiomas abutting the diaphragm.METHODS: We retrospectively reviewed our sequential experience of treating 51 large hepatic hemangiomas abutting the diaphragm in 51 patients by CT-guided or laparoscopic RF ablation due to either the presence of symptoms and/or the enlargement of hemangioma.Altogether, 24 hemangiomas were ablated via a CTguided percutaneous approach(CT-guided ablation group), and 27 hemangiomas were treated via a laparoscopic approach(laparoscopic ablation group).RESULTS: The mean diameter of the 51 hemangiomas was 9.6 ± 1.8 cm(range, 6.0-12.0 cm). There was nodifference in the diameter of hemangiomas between the two groups(P > 0.05). RF ablation was performed successfully in all patients. There was no difference in ablation times between groups(P > 0.05). There were 23 thoracic complications in 17 patients: 15(62.5%, 15/24) in the CT-guided ablation group and2(7.4%, 2/27) in the laparoscopic ablation group(P< 0.05). According to the Dindo-Clavien classification,two complications(pleural effusion and diaphragmatic rupture grade Ⅲ) were major in two patients. All others were minor(grade Ⅰ). Both major complications occurred in the CT-guided ablation group. The minor complications were treated successfully with conservative measures, and the two major complications underwent treatment by chest tube drainage and thoracoscopic surgery, respectively. Complete ablation was achieved in 91.7%(22/24) and 96.3%(26/27) in the CT-guided and the laparoscopic ablation groups,respectively(P > 0.05).CONCLUSION: Laparoscopic RF ablation therapy should be used as the first-line treatment option for large hepatic hemangiomas abutting the diaphragm.It avoids thermal injury to the diaphragm and reduces thoracic complications.

Radiofrequency ablation for hepatic hemangiomas: A consensus from a Chinese panel of experts

Recent studies have shown that radiofrequency(RF) ablation therapy is a safe, feasible, and effective procedure for hepatic hemangiomas, even huge hepatic hemangiomas. RF ablation has the following advantages in the treatment of hepatic hemangiomas: minimal invasiveness, definite efficacy, high safety, fast recovery, relatively simple operation, and wide applicability. It is necessary to formulate a widely accepted consensus among the experts in China who have extensive expertise and experience in the treatment of hepatic hemangiomas using RF ablation, which is important to standardize the application of RF ablation for the management of hepatic hemangiomas, regarding the selection of patients with suitable indications to receive RF ablation treatment, the technical details of the techniques, therapeutic effect evaluations, management of complications, etc. A final consensus by a Chinese panel of experts who have the expertise of using RF ablation to treat hepatic hemangiomas was reached by means of literature review, comprehensive discussion, and draft approval.

An interface shear damage model of chromium coating/steel substrate under thermal erosion load

The Cr-plated coating inside a gun barrel can effectively improve the barrel’s erosion resistance and thus increase the service life.However,due to the cyclic thermal load caused by high-temperature gunpowder,micro-element damage tends to occur within the Cr coating/steel substrate interface,leading to a gradual deterioration in macro-mechanical properties for the material in the related region.In order to mimic this cyclic thermal load and,thereby,study the thermal erosion behavior of the Cr coating on the barrel’s inner wall,a laser emitter is utilized in the current study.With the help of in-situ tensile test and finite element simulation results,a shear stress distribution law of the Cr coating/steel substrate and a change law of the interface ultimate shear strength are identified.Studies have shown that the Cr coating/steel substrate interface’s ultimate shear strength has a significant weakening effect due to increasing temperature.In this study,the interfacial ultimate shear strength decreases from 2.57 GPa(no erosion)to 1.02 GPa(laser power is 160 W).The data from this experiment is employed to establish a Cr coating/steel substrate interface shear damage model.And this model is used to predict the flaking process of Cr coating by finite element method.The simulation results show that the increase of coating crack spacing and coating thickness will increase the service life of gun barrel.

应用非接触性眼表综合分析仪观察T2DM和/或高血压患者的眼表特征

目的:使用非接触性眼表综合分析仪分析2型糖尿病(T2DM)和/或高血压患者眼表特征。方法:选取2017-01/2018-12在我院就诊的T2DM患者、高血压患者、T2DM合并高血压患者、无T2DM也无高血压患者各40例40眼,分析比较四组患者OSDI评分、泪河高度、眼红指数、角膜荧光素钠染色评分、非侵入性泪膜破裂时间(首次泪膜破裂时间和平均泪膜破裂时间)检测结果。结果:T2DM患者眼部不适的主观感受更为明显,T2DM和/高血压患者更容易出现眼部充血的体征。与无T2DM也无高血压的患者相比,T2DM患者的泪河高度降低,平均泪膜破裂时间明显缩短(均P<0.05),但四组患者的首次泪膜破裂时间、角膜荧光素钠染色评分均无明显差异(P>0.05)。结论:非接触性眼表综合分析仪能够无侵入地观察眼表特征,提供相对客观的量化检查结果。T2DM患者眼部稳定性较无T2DM也无高血压的患者下降,稳态更容易被打破。

Whole-genome resequencing reveals molecular imprints of anthropogenic and natural selection in wild and domesticated sheep

The abundance of domesticated sheep varieties and phenotypes is largely the result of long-term natural and artificial selection. However, there is limited information regarding the genetic mechanisms underlying phenotypic variation induced by the domestication and improvement of sheep. In this study, to explore genomic diversity and selective regions at the genome level, we sequenced the genomes of 100 sheep across 10 breeds and combined these results with publicly available genomic data from 225 individuals, including improved breeds, Chinese indigenous breeds,African indigenous breeds, and their Asian mouflon ancestor. Based on population structure, the domesticated sheep formed a monophyletic group,while the Chinese indigenous sheep showed a clear geographical distribution trend. Comparative genomic analysis of domestication identified several selective signatures, including IFI44 and IFI44L genes and PANK2 and RNF24 genes, associated with immune response and visual function.Population genomic analysis of improvement demonstrated that candidate genes of selected regions were mainly associated with pigmentation,energy metabolism, and growth development.Furthermore, the IFI44 and IFI44L genes showed a common selection signature in the genomes of 30domesticated sheep breeds. The IFI44 c. 54413058C>G mutation was selected for genotyping and population genetic validation. Results showed that the IFI44 polymorphism was significantly associated with partial immune traits. Our findings identified the population genetic basis of domesticated sheep at the whole-genome level, providing theoretical insights into the molecular mechanism underlying breed characteristics and phenotypic changes during sheep domestication and improvement.

Simulation of Synergism Effect Using Temperature Switching Irradiation on Bipolar Comparator

The synergism effect of total ionizing dose（TID） on a single event transient（SET） in a bipolar comparator is investigated. Experimental results show that the shapes of the SET are considerably influenced by the TID accumulated in low dose rates. The variation tendency of SET shapes can be accurately simulated by temperature switching irradiation. The mechanism of this synergism effect is also analyzed in brief via the operating schematic of a comparator. After the accumulation of 100 krad（Si）, the lower tendency of negative SET can be attributed to the degeneration of . The change tendency of a positive SET, either lower or higher, is dependent on the load condition that limits the output range of the comparator.

The behavior of cesium adsorption on zirconyl pyrophosphate

Zirconyl pyrophosphate(ZrP_2O_7) was prepared and Cs adsorption behavior was studied.Results show that the distribution coefficient of Cs adsorption on ZrP_2O_7 was about 2800 mL/g.Ion exchange capacity of ZrP_2O_7 was0.35 mmol/g.In dynamic tests,Cs can be separated from other fission products very well by ZrP_2O_7.The ZrP_2O_7was stable both at high temperatures and in high concentration of nitric acid.The Cs adsorption by ZrP_2O_7 is a monolayer and chemical adsorption.

Estimation of enhanced low dose rate sensitivity mechanisms using temperature switching irradiation on gate-controlled lateral PNP transistor

The mechanisms occurring when the switched temperature technique is applied,as an accelerated enhanced low dose rate sensitivity(ELDRS)test technique,are investigated in terms of a specially designed gate-controlled lateral PNP transistor(GLPNP)that used to extract the interface traps(Nit)and oxide trapped charges(Not).Electrical characteristics in GLPNP transistors induced by ^(60)Co gamma irradiation are measured in situ as a function of total dose,showing that generation of Nit in the oxide is the primary cause of base current variations for the GLPNP.Based on the analysis of the variations of Nit and Not,with switching the temperature,the properties of accelerated protons release and suppressed protons loss play critical roles in determining the increased Nit formation leading to the base current degradation with dose accumulation.Simultaneously the hydrogen cracking mechanisms responsible for additional protons release are related to the neutralization of Not extending enhanced Nit buildup.In this study the switched temperature irradiation has been employed to conservatively estimate the ELDRS of GLPNP,which provides us with a new insight into the test technique for ELDRS.