BACKGROUND Glucose and lipid metabolic disorder in patients with type 2 diabetes mellitus(T2DM)is associated with the levels of serum tumor markers of the digestive tract,such as cancer antigen(CA)199.Therefore,tumor ...BACKGROUND Glucose and lipid metabolic disorder in patients with type 2 diabetes mellitus(T2DM)is associated with the levels of serum tumor markers of the digestive tract,such as cancer antigen(CA)199.Therefore,tumor markers in T2DM are important.AIM To evaluate the expression of serum tumor markers[CA199,CA242,and carcinoembryonic antigen(CEA)]and the clinical implications of the expression in T2DM.METHODS For this observational study conducted at Hefei BOE Hospital,China,we enrolled 82 patients with first-onset T2DM and 51 controls between April 2019 and December 2020.Levels of fasting blood glucose(FBG),tumor markers(CA199,CEA,and CA242),glycosylated hemoglobin(HbA1c),etc.were measured and group index levels were compared.Moreover,FBG and HbA1c levels were correlated with tumor marker levels.Tumor markers were tested for diagnostic accuracy in patients with>9%HbA1c using the receiver operating curve(ROC)curve.RESULTS The T2DM group had high serum FBG,HbA1c,CA199,and CEA levels(P<0.05).A comparative analysis of the two groups based on HbA1c levels(Group A:HbA1c≤9%;Group B:HbA1c>9%)revealed significant differences in CEA and CA199 levels(P<0.05).The areas under the ROC curve for CEA and CA199 were 0.853 and 0.809,respectively.CA199,CEA,and CA242 levels positively correlated with HbA1c(r=0.308,0.426,and 0.551,respectively)and FBG levels(r=0.236,0.231,and 0.298,respectively).CONCLUSION As compared to controls,serum CEA and CA199 levels were higher in patients with T2DM.HbA1c and FBG levels correlated with CA199,CEA,and CA242 levels.Patients with poorly controlled blood sugar must be screened for tumor markers.展开更多
BACKGROUND Colorectal cancer is the second leading cause of cancer-related deaths among digestive tract malignancies,following gastric cancer.Sleep is of great significance for maintaining human health.The incidence o...BACKGROUND Colorectal cancer is the second leading cause of cancer-related deaths among digestive tract malignancies,following gastric cancer.Sleep is of great significance for maintaining human health.The incidence of sleep disorders in patients with cancer is approximately twice that observed in the general population.Lack of sleep can prolong hospital stays,increase the likelihood of infection,and increase mortality rates.Therefore,studying the factors related to sleep quality is significant for improving the quality of life of patients with malignant tumors of the digestive tract.AIM To investigate the relationships among sleep quality,disease uncertainty,and psychological resilience in patients undergoing chemotherapy for digestive tract malignancies.METHODS A total of 131 patients with malignant digestive tract tumors who were treated at Hefei BOE Hospital between April 2021 and September 2022 were selected as research participants.Based on their Pittsburgh Sleep Quality Index(PSQI)scores,participants were divided into either the sleep disorder group(PSQI score>7)or the normal sleep group(PSQI score≤7).The clinical data—together with the Mishel Uncertainty in Illness Scale for Adults(MUIS-A)and Connor-Davidson Resilience Scale(CD-RISC)scores—were compared.RESULTS In this study,78(59.54%)patients with digestive tract malignancies developed sleep disorders after chemotherapy.Sleep disorder incidence was higher in patients with colorectal cancer than in those with gastric and esophageal cancers(P<0.05).The total MUIS-A score and those for each item in the sleep disorder group were higher than those in the normal sleep group.The total CD-RISC score and those for each item in the sleep disorder group were lower than those in the normal sleep group(P<0.05).The PSQI scores of patients with malignant digestive tract tumors were positively correlated with the scores for lack of disease information,disease uncertainty,and unpredictability in the MUIS-A and negatively correlated with the scores for tenacity,self-improvement,and optimism in the CD-RISC(P<0.05).CONCLUSION Patients undergoing chemotherapy for digestive tract malignancies are prone to sleep problems related to disease uncertainty and psychological resilience.Therefore,interventions can be implemented to improve their sleep quality.展开更多
Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of ...Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint lithography.The hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display device.These preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application.展开更多
Researchers seldom study the optimum design of a mechanical connector for subsea oil-gas pipeline based upon the sealing performance. An optimal design method of a novel subsea pipeline mechanical connector is present...Researchers seldom study the optimum design of a mechanical connector for subsea oil-gas pipeline based upon the sealing performance. An optimal design method of a novel subsea pipeline mechanical connector is presented. By analyzing the static metal sealing mechanism, the critical condition of the sealing performance is established for this connector and the formulation method of the contact pressure on the sealing surface is created. By the method the minimum mean contact pressure of the 8.625 inch connector is calculated as 361 MPa, which is the constraint condition in the optimum design of connector.The finite element model is created in ANSYS Parametric Design Language(APDL) and the structure is optimized by the zero-order method, with variance of contact pressure as the objective function, and mean contact pressures and plastic strains as constraint variables. The optimization shows that variances of contact pressure on two sealing surfaces decrease by 72.41% and 89.33%, respectively, and mean contact pressures increase by 31.18% and 52.84%, respectively. The comparison of the optimal connectors and non-optimal connectors in the water pressure experiments and bending experiments shows that the sealing ability of optimized connectors is much higher than the rated pressure of 4.5 MPa, and the optimal connectors don’t leak under the bending moment of 52.2 kN·m.This research provides the formulation to solve contact pressure on the sealing surface and a structure optimization method to design the connectors with various dimensions.展开更多
We propose a high-performance path planning algorithm for automatic target tracking in the applications of real-time simulation and visualization of large-scale terrain datasets, with a large number of moving objects ...We propose a high-performance path planning algorithm for automatic target tracking in the applications of real-time simulation and visualization of large-scale terrain datasets, with a large number of moving objects (such as vehicles) tracking multiple moving targets. By using a modified Dijkstra's algorithm, an optimal path between each vehicle-target pair over a weighted grid-presented terrain is computed and updated to eliminate the problem of local minima and losing of tracking. Then, a dynamic path re-planning strategy using multi-resolution representation of a dynamic updating region is proposed to achieve high-performance by trading-off precision for efficiency, while guaranteeing accuracy. Primary experimental results showed that our algorithm successfully achieved l0 to 96 frames per second interactive path-replanning rates during a terrain simulation scenario with 10 to 100 vehicles and multiple moving targets.展开更多
A novel Sb2O3/Sb2S3/FeOOH photoanode was fabricated via a simple solution impregnation method along with chemical bath deposition and post-sulfidation.The X-ray diffractometry,Raman measurement,and X-ray photoelectron...A novel Sb2O3/Sb2S3/FeOOH photoanode was fabricated via a simple solution impregnation method along with chemical bath deposition and post-sulfidation.The X-ray diffractometry,Raman measurement,and X-ray photoelectron spectroscopy show that the Sb2O3/Sb2S3/FeOOH thin films are successfully prepared.SEM−EDS analyses reveal that the surface of Sb2O3/Sb2S3 thin films becomes rough after the immersion in the FeCl3 solution.The optimized impregnation time is found to be 8 h.The FeOOH co-catalyst loaded Sb2O3/Sb2S3 electrode exhibits an enhanced photocurrent density of 0.45 mA/cm2 at 1.23 V versus RHE under simulated 1 sun,which is approximately 1.41 times compared to the photocurrent density of the unloaded one.Through the further tests of UV−Vis spectroscopy,the electrochemical impedance spectra,and the PEC measurements,the enhancement can result from the increased light-harvesting ability,the decreased interface transmission impedance,and the remarkably enhanced carrier injection efficiency.展开更多
We report on the fabrication and electrical characteristics of Ga-doped ZnO thin film transistors(TFTs).Low Ga-doped(0.7wt%)ZnO thin films were deposited on SiO_(2)/p−Si substrates by rf magnetron sputtering.The GZO T...We report on the fabrication and electrical characteristics of Ga-doped ZnO thin film transistors(TFTs).Low Ga-doped(0.7wt%)ZnO thin films were deposited on SiO_(2)/p−Si substrates by rf magnetron sputtering.The GZO TFTs show a mobility of 1.76 cm2/V⋅s,an on/off ratio of 1.0×10^(6),and a threshold voltage of 35 V.The time−dependent instability of the TFT is studied.The VTH shifts negatively.In addition,the device shows a decrease of the on/off ratio,mainly due to the increase of the off-current.The mechanisms of instability are discussed.展开更多
Metallic biomaterials are increasingly being used in various medical applications due to their high strength,fracture resistance,good electrical conductivity,and biocompatibility.However,their practical applications h...Metallic biomaterials are increasingly being used in various medical applications due to their high strength,fracture resistance,good electrical conductivity,and biocompatibility.However,their practical applications have been largely limited due to poor surface performance.Laser microprocessing is an advanced method of enhancing the surface-related properties of biomaterials.This work demonstrates the capability of laser microprocessing for biomedical metallic materials including magnesium and titanium alloys,with potential applications in cell adhesion and liquid biopsy.We investigate laser-material interaction,microstructural evolution,and surface performance,and analyze cell behavior and the surface-enhanced Raman scattering(SERS)effect.Furthermore,we explore a theoretical study on the laser microprocessing of metallic alloys that shows interesting results with potential applications.The results show that cells exhibit good adhesion behavior at the surface of the laser-treated surface,with a preferential direction based on the textured structure.A significant SERS enhancement of 6×10^3 can be obtained at the laser-textured surface during Raman measurement.展开更多
This research focuses on tin whisker growth under two different environmental conditions namely hygrothermal and a salt solution. Tin coated brass coupons were used for this study to analyze the growth of tin whiskers...This research focuses on tin whisker growth under two different environmental conditions namely hygrothermal and a salt solution. Tin coated brass coupons were used for this study to analyze the growth of tin whiskers over time. Their growth rates were examined periodically using optical and scanning electron microscopy. The physical characteristics of the tin whiskers were identified for each environmental condition. It was discovered that submersion of tin coated brass substrates in 5% salt solution considerably increased the density (number of whiskers per unit area), and the length of the whiskers. In addition, it was found that the geometry and aspect ratio of tin whiskers were different for each environment.展开更多
BACKGROUND Although norepinephrine injection is commonly used in emergency situations,it is associated with risks for elderly patients with spasmodic liver pain.This study explores the safety and effectiveness of mebe...BACKGROUND Although norepinephrine injection is commonly used in emergency situations,it is associated with risks for elderly patients with spasmodic liver pain.This study explores the safety and effectiveness of mebendazole injection,an alternative treatment option,for the emergency management of spasmodic abdominal pain,while minimizing adverse reactions,in elderly patients.AIM To explore the development of norepinephrine injection and the adverse reactions of this drug in emergency elderly patients with spasmodic liver pain.METHODS The control group consisted of 56 elderly patients visiting our hospital from January 2021 to December 2021.After hospital admission,the control group was intravenously administered tolopin.The experimental group consisted of 56 emergency patients with spasmodic abdominal pain who visited our hospital until June 2022.After hospital admission,the experimental group was intravenously administered toloxazole.The two groups were treated for 3 d.The disappearance of clinical symptoms was observed before and after the treatment,and the difference in adverse reactions between the two groups was compared.RESULTS The pain of the wife,fire,diarrhea,drowning,and surrounding time disappeared in the experimental group.No statistical difference was observed between the experimental and control groups in visual pain analog scale(VAS)scores before and after the treatment(P>0.05).The VAS scores of abdominal pain severity after 0.5 h,1.0 h,and after 6.0 h of treatment were significantly lower for the experimental group than for the control group.After the treatment,the therapeutic effect in the experimental group was higher and statistically significant than that in the control group(P<0.05).The probability of adverse reactions before the treatment was lower in the experimental group than in the control group.CONCLUSION During emergency,mebendazole injection exhibited a good therapeutic value when used for the clinical treatment of elderly patients with spasmodic stomach pain.It accelerated the disappearance of clinical symptoms such as stomach pain,reduced the stomach weight,and improved clinical activity.Reducing and promoting the frequency of high treatment safety with mebendazole injection is worthwhile.展开更多
BACKGROUND Synchronous combined hepatocellular-cholangiocarcinoma(CHC)and hepatocellular carcinoma(HCC)is very rare,with few literature reports and poor clinical outcomes associated with the disorder.Surgical resectio...BACKGROUND Synchronous combined hepatocellular-cholangiocarcinoma(CHC)and hepatocellular carcinoma(HCC)is very rare,with few literature reports and poor clinical outcomes associated with the disorder.Surgical resection is the main treatment,which makes the preoperative diagnosis very important.However,due to imaging manifestations overlapping with HCC,diagnosis of this type of synchronous cancer is challenging and it tends to be misdiagnosed as multiple HCC.Herein,we report the contrast-enhanced ultrasound(CEUS)manifestations of a case of synchronous CHC and HCC,aiming at adding to the understanding of this disease.CEUS displayed exquisite vascularity and tissue perfusion in real time with good spatial and temporal resolution and more accurately reflect tumor washin and washout times than contrast-enhanced computed tomography(CT)in this case.CASE SUMMARY The patient was a 69-year-old female with a 20-year history of chronic hepatitis B.Due to months of epigastric pain and anorexia,she reffered to our hospital for treatment.Five days before hospitalization,abdominal magnetic resonance imaging performed at another hospital detected a space-occupying lesion in the liver.After her hospitalization,laboratory tests showed elevated alpha-fetoprotein and carbohydrate antigen 19-9 level.Two suspicious liver lesions located in S4 and S6,respectively,were identified in a cirrhotic background by abdominal contrast-enhanced CT(CECT).Furthermore,the lesion in S4 and S6 were detected by CEUS and assigned to CEUS LI-RADS 5 and M categories,respectively.The patient underwent tumor radical resections.Post-operative pathology confirmed the S4 and S6 lesions to be HCC and CHC,respectively.A newly-found suspicious liver nodule with potential malignancy was detected in liver S1 by both CEUS and CECT 7 mo after operation.CONCLUSION The CEUS characteristics of CHC and HCC are different.CEUS features in combination with clinical information could help in effective diagnosis,clinical decision-making and better prognosis.展开更多
The structure ofV2O5-P2O5-Sb2O3-Bi2O3glass and its state of crystallization were studied by means of infrared spectroscopy and X-ray diffraction analysis. The results indicate that, in this glass, V and P exist mainly...The structure ofV2O5-P2O5-Sb2O3-Bi2O3glass and its state of crystallization were studied by means of infrared spectroscopy and X-ray diffraction analysis. The results indicate that, in this glass, V and P exist mainly in the form of a single-stranded linear (VO3)n and an isolated (PO4) tetrahedral with no double bond. Partial V and P are connected through O, forming an amorphous structure of layered vana- dium phosphate. Trivalent Sb3+ and Bi3+ open the V=O bond and appear in interlayers, so a weak three-dimensional structure is connected successfully. Along with the substitution of Sb203 for partial V205 or that of P205 for partial V205, the network structure of the glass is rein- forced, and the crystallization is reduced.展开更多
Thermoelectric performances of free-standing polythiophene (PT) and poly(3-methylthiophene) (PMeT) nanofilms with high tensile strength electrosynthesized from boron trifluoride diethyl etherate (BFEE) are sys...Thermoelectric performances of free-standing polythiophene (PT) and poly(3-methylthiophene) (PMeT) nanofilms with high tensile strength electrosynthesized from boron trifluoride diethyl etherate (BFEE) are systematically investigated. They display decent electric conductivity (47 and 73S.cm^-1), high Seebeck coefficient (130 and 76μV.K^-1) and low thermal conductivity (0.17 and 0.15 W.m^-1.K^-1) at room temperature. Their figure of merit can reach 3.0 × 10^-2 at 250K, higher than that of many other conducting polymers. The decrease of charge carrier concentration resulting from volatile and water-sensitive dopants from BFEE leads to the decrease of electrical conductivity but a substantial increase of the Seebeck coet^cient, making their figure-of-merit values maintained at more than 10-2 even after prolonged storage (two months). Moreover, free-standing PT and PMeT exhibit much better thermoelectric performances than those in pressed pellets due to the good arrangement of the polymer chains and preferably oriented structure in films. It therefore provides a way to improve the thermo- electric performances of conducting polymers by controlling regularity of the extended conjugated chain structure and/or the chain packing to achieve high charge mobility.展开更多
The measurement of volatile organic compound (VOC) emissions from materials is normally conducted under standard environmental conditions, i.e., (23±1) ℃ temperature, (50±5)% relative humidity, and 0.1 MPa ...The measurement of volatile organic compound (VOC) emissions from materials is normally conducted under standard environmental conditions, i.e., (23±1) ℃ temperature, (50±5)% relative humidity, and 0.1 MPa pressure. In order to define VOC emissions in non-standard environmental conditions, it is necessary to study the impact of key environmental parameters on emissions. This paper evaluates the impact of air pressure on VOC emissions from an aircraft carpet. The correlation between air pressure and VOC diffusion coefficient is derived, and the emission model is applied to studying the VOC emissions under pressure conditions of less than 0.1 MPa.展开更多
In order to solve the life problem of vacuum fluorescent display (VFD) within shorter time, and reduce the life prediction cost, a constant-step stress accelerated life test was performed with its cathode temperature ...In order to solve the life problem of vacuum fluorescent display (VFD) within shorter time, and reduce the life prediction cost, a constant-step stress accelerated life test was performed with its cathode temperature increased. Statistical analysis was done by applying logarithmic normal distribution for describing the life, and least square method (LSM) for estimating logarithmic normal parameters. Self-designed special software was used to predict the VFD life. It is verified by numerical results that the VFD life follows logarithmic normal distribution, and that the life-stress relationship satisfies linear Arrhenius equation completely. The accurate calculation of the key parameters enables the rapid estimation of VFD life.展开更多
In this study,indium oxide(In2O3) thin-film transistors(TFTs) are fabricated by two kinds of low temperature solution-processed technologies(Ta ≤ 300℃),i.e.,water-based(DIW-based) process and alkoxide-based...In this study,indium oxide(In2O3) thin-film transistors(TFTs) are fabricated by two kinds of low temperature solution-processed technologies(Ta ≤ 300℃),i.e.,water-based(DIW-based) process and alkoxide-based(2-ME-based)process.The thickness values,crystallization properties,chemical structures,surface roughness values,and optical properties of In2O3 thin-films and the electrical characteristics of In2O3 TFTs are studied at different annealing temperatures.Thermal annealing at higher temperature leads to an increase in the saturation mobility(μsat) and a negative shift in the threshold voltage(VTH).The DIW-based processed In2O3-TFT annealed at 300℃ exhibits excellent device performance,and one annealed at 200℃ exhibits an acceptable μsat of 0.86 cm^2/V·s comparable to that of a-Si:H TFTs,whereas the 2-ME-based TFT annealed at 300℃ exhibits an abundant μsat of 1.65 cm^2/Vs and one annealed at 200℃ is inactive.The results are attributed to the fact that the DIW-based process induces a higher degree of oxidation and less defect states than the 2-ME-based process at the same temperature.The DIW-based process for fabricating the In2O3 TFT opens the way for the development of nontoxic,low-cost,and low-temperature oxide electronics.展开更多
文摘BACKGROUND Glucose and lipid metabolic disorder in patients with type 2 diabetes mellitus(T2DM)is associated with the levels of serum tumor markers of the digestive tract,such as cancer antigen(CA)199.Therefore,tumor markers in T2DM are important.AIM To evaluate the expression of serum tumor markers[CA199,CA242,and carcinoembryonic antigen(CEA)]and the clinical implications of the expression in T2DM.METHODS For this observational study conducted at Hefei BOE Hospital,China,we enrolled 82 patients with first-onset T2DM and 51 controls between April 2019 and December 2020.Levels of fasting blood glucose(FBG),tumor markers(CA199,CEA,and CA242),glycosylated hemoglobin(HbA1c),etc.were measured and group index levels were compared.Moreover,FBG and HbA1c levels were correlated with tumor marker levels.Tumor markers were tested for diagnostic accuracy in patients with>9%HbA1c using the receiver operating curve(ROC)curve.RESULTS The T2DM group had high serum FBG,HbA1c,CA199,and CEA levels(P<0.05).A comparative analysis of the two groups based on HbA1c levels(Group A:HbA1c≤9%;Group B:HbA1c>9%)revealed significant differences in CEA and CA199 levels(P<0.05).The areas under the ROC curve for CEA and CA199 were 0.853 and 0.809,respectively.CA199,CEA,and CA242 levels positively correlated with HbA1c(r=0.308,0.426,and 0.551,respectively)and FBG levels(r=0.236,0.231,and 0.298,respectively).CONCLUSION As compared to controls,serum CEA and CA199 levels were higher in patients with T2DM.HbA1c and FBG levels correlated with CA199,CEA,and CA242 levels.Patients with poorly controlled blood sugar must be screened for tumor markers.
基金National Nature Science foundation of China,No.81900755and the Health Commission of Shanghai Municipality,No.20194Yo384.
文摘BACKGROUND Colorectal cancer is the second leading cause of cancer-related deaths among digestive tract malignancies,following gastric cancer.Sleep is of great significance for maintaining human health.The incidence of sleep disorders in patients with cancer is approximately twice that observed in the general population.Lack of sleep can prolong hospital stays,increase the likelihood of infection,and increase mortality rates.Therefore,studying the factors related to sleep quality is significant for improving the quality of life of patients with malignant tumors of the digestive tract.AIM To investigate the relationships among sleep quality,disease uncertainty,and psychological resilience in patients undergoing chemotherapy for digestive tract malignancies.METHODS A total of 131 patients with malignant digestive tract tumors who were treated at Hefei BOE Hospital between April 2021 and September 2022 were selected as research participants.Based on their Pittsburgh Sleep Quality Index(PSQI)scores,participants were divided into either the sleep disorder group(PSQI score>7)or the normal sleep group(PSQI score≤7).The clinical data—together with the Mishel Uncertainty in Illness Scale for Adults(MUIS-A)and Connor-Davidson Resilience Scale(CD-RISC)scores—were compared.RESULTS In this study,78(59.54%)patients with digestive tract malignancies developed sleep disorders after chemotherapy.Sleep disorder incidence was higher in patients with colorectal cancer than in those with gastric and esophageal cancers(P<0.05).The total MUIS-A score and those for each item in the sleep disorder group were higher than those in the normal sleep group.The total CD-RISC score and those for each item in the sleep disorder group were lower than those in the normal sleep group(P<0.05).The PSQI scores of patients with malignant digestive tract tumors were positively correlated with the scores for lack of disease information,disease uncertainty,and unpredictability in the MUIS-A and negatively correlated with the scores for tenacity,self-improvement,and optimism in the CD-RISC(P<0.05).CONCLUSION Patients undergoing chemotherapy for digestive tract malignancies are prone to sleep problems related to disease uncertainty and psychological resilience.Therefore,interventions can be implemented to improve their sleep quality.
基金supported by the National Natural Science Foundation of China(22288102 and 22278027).
文摘Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint lithography.The hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display device.These preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application.
基金Supported by National Natural Science Foundation of China(Grant Nos.51279042,51105088)
文摘Researchers seldom study the optimum design of a mechanical connector for subsea oil-gas pipeline based upon the sealing performance. An optimal design method of a novel subsea pipeline mechanical connector is presented. By analyzing the static metal sealing mechanism, the critical condition of the sealing performance is established for this connector and the formulation method of the contact pressure on the sealing surface is created. By the method the minimum mean contact pressure of the 8.625 inch connector is calculated as 361 MPa, which is the constraint condition in the optimum design of connector.The finite element model is created in ANSYS Parametric Design Language(APDL) and the structure is optimized by the zero-order method, with variance of contact pressure as the objective function, and mean contact pressures and plastic strains as constraint variables. The optimization shows that variances of contact pressure on two sealing surfaces decrease by 72.41% and 89.33%, respectively, and mean contact pressures increase by 31.18% and 52.84%, respectively. The comparison of the optimal connectors and non-optimal connectors in the water pressure experiments and bending experiments shows that the sealing ability of optimized connectors is much higher than the rated pressure of 4.5 MPa, and the optimal connectors don’t leak under the bending moment of 52.2 kN·m.This research provides the formulation to solve contact pressure on the sealing surface and a structure optimization method to design the connectors with various dimensions.
基金Project partially supported by NSF (No. CCR0306438) and theBoeing Company, USA
文摘We propose a high-performance path planning algorithm for automatic target tracking in the applications of real-time simulation and visualization of large-scale terrain datasets, with a large number of moving objects (such as vehicles) tracking multiple moving targets. By using a modified Dijkstra's algorithm, an optimal path between each vehicle-target pair over a weighted grid-presented terrain is computed and updated to eliminate the problem of local minima and losing of tracking. Then, a dynamic path re-planning strategy using multi-resolution representation of a dynamic updating region is proposed to achieve high-performance by trading-off precision for efficiency, while guaranteeing accuracy. Primary experimental results showed that our algorithm successfully achieved l0 to 96 frames per second interactive path-replanning rates during a terrain simulation scenario with 10 to 100 vehicles and multiple moving targets.
基金Project(51674298)supported by the National Natural Science Foundation of ChinaProject(2017JJ3384)supported by the Natural Science Foundation of Hunan Province,ChinaProject(2018M630910)supported by the China Postdoctoral Science Foundation。
文摘A novel Sb2O3/Sb2S3/FeOOH photoanode was fabricated via a simple solution impregnation method along with chemical bath deposition and post-sulfidation.The X-ray diffractometry,Raman measurement,and X-ray photoelectron spectroscopy show that the Sb2O3/Sb2S3/FeOOH thin films are successfully prepared.SEM−EDS analyses reveal that the surface of Sb2O3/Sb2S3 thin films becomes rough after the immersion in the FeCl3 solution.The optimized impregnation time is found to be 8 h.The FeOOH co-catalyst loaded Sb2O3/Sb2S3 electrode exhibits an enhanced photocurrent density of 0.45 mA/cm2 at 1.23 V versus RHE under simulated 1 sun,which is approximately 1.41 times compared to the photocurrent density of the unloaded one.Through the further tests of UV−Vis spectroscopy,the electrochemical impedance spectra,and the PEC measurements,the enhancement can result from the increased light-harvesting ability,the decreased interface transmission impedance,and the remarkably enhanced carrier injection efficiency.
基金Supported by the National Natural Science Foundation of China under Grant No 50972007the Beijing Municipal Natural Science Foundation under Grant No 4092035+2 种基金the National Basic Research Program of China under Grant No 2011CB932703the National Science Fund for Distinguished Young Scholars under Grant No 60825407the Special Items Fund of the Beijing Municipal Commission of Education,and the Opened Fund of the State Key Laboratory on Integrated Optoelectronics.
文摘We report on the fabrication and electrical characteristics of Ga-doped ZnO thin film transistors(TFTs).Low Ga-doped(0.7wt%)ZnO thin films were deposited on SiO_(2)/p−Si substrates by rf magnetron sputtering.The GZO TFTs show a mobility of 1.76 cm2/V⋅s,an on/off ratio of 1.0×10^(6),and a threshold voltage of 35 V.The time−dependent instability of the TFT is studied.The VTH shifts negatively.In addition,the device shows a decrease of the on/off ratio,mainly due to the increase of the off-current.The mechanisms of instability are discussed.
基金the National Key R&D Program of China(2018YFB1107400)the National Key Basic Research Program of China(2015CB059900)+1 种基金the National Natural Science Foundation of China(51705013)the Beijing Natural Science Foundation(3162019 and J170002).
文摘Metallic biomaterials are increasingly being used in various medical applications due to their high strength,fracture resistance,good electrical conductivity,and biocompatibility.However,their practical applications have been largely limited due to poor surface performance.Laser microprocessing is an advanced method of enhancing the surface-related properties of biomaterials.This work demonstrates the capability of laser microprocessing for biomedical metallic materials including magnesium and titanium alloys,with potential applications in cell adhesion and liquid biopsy.We investigate laser-material interaction,microstructural evolution,and surface performance,and analyze cell behavior and the surface-enhanced Raman scattering(SERS)effect.Furthermore,we explore a theoretical study on the laser microprocessing of metallic alloys that shows interesting results with potential applications.The results show that cells exhibit good adhesion behavior at the surface of the laser-treated surface,with a preferential direction based on the textured structure.A significant SERS enhancement of 6×10^3 can be obtained at the laser-textured surface during Raman measurement.
文摘This research focuses on tin whisker growth under two different environmental conditions namely hygrothermal and a salt solution. Tin coated brass coupons were used for this study to analyze the growth of tin whiskers over time. Their growth rates were examined periodically using optical and scanning electron microscopy. The physical characteristics of the tin whiskers were identified for each environmental condition. It was discovered that submersion of tin coated brass substrates in 5% salt solution considerably increased the density (number of whiskers per unit area), and the length of the whiskers. In addition, it was found that the geometry and aspect ratio of tin whiskers were different for each environment.
文摘BACKGROUND Although norepinephrine injection is commonly used in emergency situations,it is associated with risks for elderly patients with spasmodic liver pain.This study explores the safety and effectiveness of mebendazole injection,an alternative treatment option,for the emergency management of spasmodic abdominal pain,while minimizing adverse reactions,in elderly patients.AIM To explore the development of norepinephrine injection and the adverse reactions of this drug in emergency elderly patients with spasmodic liver pain.METHODS The control group consisted of 56 elderly patients visiting our hospital from January 2021 to December 2021.After hospital admission,the control group was intravenously administered tolopin.The experimental group consisted of 56 emergency patients with spasmodic abdominal pain who visited our hospital until June 2022.After hospital admission,the experimental group was intravenously administered toloxazole.The two groups were treated for 3 d.The disappearance of clinical symptoms was observed before and after the treatment,and the difference in adverse reactions between the two groups was compared.RESULTS The pain of the wife,fire,diarrhea,drowning,and surrounding time disappeared in the experimental group.No statistical difference was observed between the experimental and control groups in visual pain analog scale(VAS)scores before and after the treatment(P>0.05).The VAS scores of abdominal pain severity after 0.5 h,1.0 h,and after 6.0 h of treatment were significantly lower for the experimental group than for the control group.After the treatment,the therapeutic effect in the experimental group was higher and statistically significant than that in the control group(P<0.05).The probability of adverse reactions before the treatment was lower in the experimental group than in the control group.CONCLUSION During emergency,mebendazole injection exhibited a good therapeutic value when used for the clinical treatment of elderly patients with spasmodic stomach pain.It accelerated the disappearance of clinical symptoms such as stomach pain,reduced the stomach weight,and improved clinical activity.Reducing and promoting the frequency of high treatment safety with mebendazole injection is worthwhile.
文摘BACKGROUND Synchronous combined hepatocellular-cholangiocarcinoma(CHC)and hepatocellular carcinoma(HCC)is very rare,with few literature reports and poor clinical outcomes associated with the disorder.Surgical resection is the main treatment,which makes the preoperative diagnosis very important.However,due to imaging manifestations overlapping with HCC,diagnosis of this type of synchronous cancer is challenging and it tends to be misdiagnosed as multiple HCC.Herein,we report the contrast-enhanced ultrasound(CEUS)manifestations of a case of synchronous CHC and HCC,aiming at adding to the understanding of this disease.CEUS displayed exquisite vascularity and tissue perfusion in real time with good spatial and temporal resolution and more accurately reflect tumor washin and washout times than contrast-enhanced computed tomography(CT)in this case.CASE SUMMARY The patient was a 69-year-old female with a 20-year history of chronic hepatitis B.Due to months of epigastric pain and anorexia,she reffered to our hospital for treatment.Five days before hospitalization,abdominal magnetic resonance imaging performed at another hospital detected a space-occupying lesion in the liver.After her hospitalization,laboratory tests showed elevated alpha-fetoprotein and carbohydrate antigen 19-9 level.Two suspicious liver lesions located in S4 and S6,respectively,were identified in a cirrhotic background by abdominal contrast-enhanced CT(CECT).Furthermore,the lesion in S4 and S6 were detected by CEUS and assigned to CEUS LI-RADS 5 and M categories,respectively.The patient underwent tumor radical resections.Post-operative pathology confirmed the S4 and S6 lesions to be HCC and CHC,respectively.A newly-found suspicious liver nodule with potential malignancy was detected in liver S1 by both CEUS and CECT 7 mo after operation.CONCLUSION The CEUS characteristics of CHC and HCC are different.CEUS features in combination with clinical information could help in effective diagnosis,clinical decision-making and better prognosis.
文摘The structure ofV2O5-P2O5-Sb2O3-Bi2O3glass and its state of crystallization were studied by means of infrared spectroscopy and X-ray diffraction analysis. The results indicate that, in this glass, V and P exist mainly in the form of a single-stranded linear (VO3)n and an isolated (PO4) tetrahedral with no double bond. Partial V and P are connected through O, forming an amorphous structure of layered vana- dium phosphate. Trivalent Sb3+ and Bi3+ open the V=O bond and appear in interlayers, so a weak three-dimensional structure is connected successfully. Along with the substitution of Sb203 for partial V205 or that of P205 for partial V205, the network structure of the glass is rein- forced, and the crystallization is reduced.
基金Supported by the National Natural Science Foundation of China under Grant No 50663001 and 50963002, the Jiangxi Jinggang Star Project, and Jiangxi Provincial Department of Education (G J J09574, YC08A096).
文摘Thermoelectric performances of free-standing polythiophene (PT) and poly(3-methylthiophene) (PMeT) nanofilms with high tensile strength electrosynthesized from boron trifluoride diethyl etherate (BFEE) are systematically investigated. They display decent electric conductivity (47 and 73S.cm^-1), high Seebeck coefficient (130 and 76μV.K^-1) and low thermal conductivity (0.17 and 0.15 W.m^-1.K^-1) at room temperature. Their figure of merit can reach 3.0 × 10^-2 at 250K, higher than that of many other conducting polymers. The decrease of charge carrier concentration resulting from volatile and water-sensitive dopants from BFEE leads to the decrease of electrical conductivity but a substantial increase of the Seebeck coet^cient, making their figure-of-merit values maintained at more than 10-2 even after prolonged storage (two months). Moreover, free-standing PT and PMeT exhibit much better thermoelectric performances than those in pressed pellets due to the good arrangement of the polymer chains and preferably oriented structure in films. It therefore provides a way to improve the thermo- electric performances of conducting polymers by controlling regularity of the extended conjugated chain structure and/or the chain packing to achieve high charge mobility.
基金Project supported by Boeing Commercial Airplanes,USA
文摘The measurement of volatile organic compound (VOC) emissions from materials is normally conducted under standard environmental conditions, i.e., (23±1) ℃ temperature, (50±5)% relative humidity, and 0.1 MPa pressure. In order to define VOC emissions in non-standard environmental conditions, it is necessary to study the impact of key environmental parameters on emissions. This paper evaluates the impact of air pressure on VOC emissions from an aircraft carpet. The correlation between air pressure and VOC diffusion coefficient is derived, and the emission model is applied to studying the VOC emissions under pressure conditions of less than 0.1 MPa.
文摘In order to solve the life problem of vacuum fluorescent display (VFD) within shorter time, and reduce the life prediction cost, a constant-step stress accelerated life test was performed with its cathode temperature increased. Statistical analysis was done by applying logarithmic normal distribution for describing the life, and least square method (LSM) for estimating logarithmic normal parameters. Self-designed special software was used to predict the VFD life. It is verified by numerical results that the VFD life follows logarithmic normal distribution, and that the life-stress relationship satisfies linear Arrhenius equation completely. The accurate calculation of the key parameters enables the rapid estimation of VFD life.
基金Project supported by the National Natural Science Foundation of China(Grant No.61675024)the National Basic Research Program of China(Grant No.2014CB643600)
文摘In this study,indium oxide(In2O3) thin-film transistors(TFTs) are fabricated by two kinds of low temperature solution-processed technologies(Ta ≤ 300℃),i.e.,water-based(DIW-based) process and alkoxide-based(2-ME-based)process.The thickness values,crystallization properties,chemical structures,surface roughness values,and optical properties of In2O3 thin-films and the electrical characteristics of In2O3 TFTs are studied at different annealing temperatures.Thermal annealing at higher temperature leads to an increase in the saturation mobility(μsat) and a negative shift in the threshold voltage(VTH).The DIW-based processed In2O3-TFT annealed at 300℃ exhibits excellent device performance,and one annealed at 200℃ exhibits an acceptable μsat of 0.86 cm^2/V·s comparable to that of a-Si:H TFTs,whereas the 2-ME-based TFT annealed at 300℃ exhibits an abundant μsat of 1.65 cm^2/Vs and one annealed at 200℃ is inactive.The results are attributed to the fact that the DIW-based process induces a higher degree of oxidation and less defect states than the 2-ME-based process at the same temperature.The DIW-based process for fabricating the In2O3 TFT opens the way for the development of nontoxic,low-cost,and low-temperature oxide electronics.