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Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure 被引量:1
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作者 Ming Li Da-Hao Yuan +2 位作者 Zhi Yang Teng-Xiang Luw Xiao-Biao Zou 《World Journal of Clinical Cases》 SCIE 2024年第18期3461-3467,共7页
BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.Howeve... BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF. 展开更多
关键词 Serum cystatin C Monocyte/high-density lipoprotein-C ratio Uric acid Coronary heart disease Heart failure Risk stratification
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Tandem hydroalkylation and deoxygenation of lignin-derived phenolics to synthesize high-density fuels
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作者 Rui Yu Zhensheng Shen +6 位作者 Yanan Liu Chengxiang Shi Juncong Qu Lun Pan Zhenfeng Huang Xiangwen Zhan g Ji-Jun Zou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期104-109,共6页
Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels usin... Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil. 展开更多
关键词 high-density fuel BIOFUEL Hydrogenation ALKYLATION Lignin Phenolics
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Kinetic-Thermodynamic Promotion Engineering toward High-Density Hierarchical and Zn-Doping Activity-Enhancing ZnNiO@CF for High-Capacity Desalination
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作者 Jie Ma Siyang Xing +2 位作者 Yabo Wang Jinhu Yang Fei Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期35-50,共16页
Despite the promising potential of transition metal oxides(TMOs)as capacitive deionization(CDI)electrodes,the actual capacity of TMOs electrodes for sodium storage is significantly lower than the theoretical capacity,... Despite the promising potential of transition metal oxides(TMOs)as capacitive deionization(CDI)electrodes,the actual capacity of TMOs electrodes for sodium storage is significantly lower than the theoretical capacity,posing a major obstacle.Herein,we prepared the kinetically favorable Zn_(x)Ni_(1−x)O electrode in situ growth on carbon felt(Zn_(x)Ni_(1−x)O@CF)through constraining the rate of OH^(−)generation in the hydrothermal method.Zn_(x)Ni_(1−x)O@CF exhibited a high-density hierarchical nanosheet structure with three-dimensional open pores,benefitting the ion transport/electron transfer.And tuning the moderate amount of redox-inert Zn-doping can enhance surface electroactive sites,actual activity of redox-active Ni species,and lower adsorption energy,promoting the adsorption kinetic and thermodynamic of the Zn_(0.2)Ni_(0.8)O@CF.Benefitting from the kinetic-thermodynamic facilitation mechanism,Zn_(0.2)Ni_(0.8)O@CF achieved ultrahigh desalination capacity(128.9 mgNaCl g^(-1)),ultra-low energy consumption(0.164 kW h kgNaCl^(-1)),high salt removal rate(1.21 mgNaCl g^(-1) min^(-1)),and good cyclability.The thermodynamic facilitation and Na^(+)intercalation mechanism of Zn_(0.2)Ni_(0.8)O@CF are identified by the density functional theory calculations and electrochemical quartz crystal microbalance with dissipation monitoring,respectively.This research provides new insights into controlling electrochemically favorable morphology and demonstrates that Zn-doping,which is redox-inert,is essential for enhancing the electrochemical performance of CDI electrodes. 展开更多
关键词 Zinc-nickel metal oxide high-density hierarchical Capacitive deionization Zinc-doping
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Oxygen variation in titanium powder and metal injection molding
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作者 Junping Shen Chang Liu +7 位作者 Muhammad Dilawer Hayat Jianan Chen Hanqing Tian Fusheng Xin Gang Chen Fei Yang Mingli Qin Xuanhui Qu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2706-2713,共8页
The control of oxygen is paramount in achieving high-performance titanium(Ti)parts by powder metallurgy such as metal in-jection molding(MIM).In this study,we purposely selected the Ti and Ti-6Al-4V powders as the ref... The control of oxygen is paramount in achieving high-performance titanium(Ti)parts by powder metallurgy such as metal in-jection molding(MIM).In this study,we purposely selected the Ti and Ti-6Al-4V powders as the reference materials since these two are the most representative Ti materials in the industry.Herein,hydride-dehydride(HDH)Ti powders were pre-oxidized to examine the ef-fect of oxygen variation on the characteristics of oxide layer on the particle surface and its resultant color feature.The results indicate that the thickness and Ti oxide level(Ti^(0)→Ti^(4+))of the oxide layer on the HDH Ti powders increased as the oxygen content increased,lead-ing to the transition of color appearance from grey,brown to blue.This work aids in the powder feedstock selection at the initial stage in powder metallurgy.In addition,the development of oxygen content was comprehensively studied during the MIM process using the gas-atomized(GA)Ti-6Al-4V powders.Particularly,the oxygen variation in the form of oxide layer,the change of oxygen content in the powders,and the relevant parts were investigated during the processes of kneading,injection,debinding,and sintering.The oxygen vari-ation was mainly concentrated in the sintering stage,and the content increased with the increase of sintering temperature.The variation of oxygen content during the MIM process demonstrates the crucial role of powder feedstock and sintering stage in controlling oxygen con-tent.This work provides a piece of valuable information on oxygen detecting,control,and manipulation for the powder and processing in the industry of Ti and its alloys by powder metallurgy. 展开更多
关键词 titanium alloys OXYGEN metal injection molding powder metallurgy
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Effects of the Water-Cement Ratio and the Molding Temperature on the Hydration Heat of Cement
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作者 代金鹏 HE Jie +1 位作者 WANG Qicai LOU Xuyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期990-998,共9页
The effects of the water-cement ratio and the molding temperature on the hydration heat of cement were investigated with semi-adiabatic calorimetry.The specimens were prepared with water-cement ratios of 0.31,0.38,and... The effects of the water-cement ratio and the molding temperature on the hydration heat of cement were investigated with semi-adiabatic calorimetry.The specimens were prepared with water-cement ratios of 0.31,0.38,and 0.45,and the molding temperature was specified at 10 and 20℃.The experimental results show that,as the water-binder ratio increases,the value of the second temperature peak on the temperature curve of the cement paste decreases,and the age at which the peak appears is delayed.The higher the water-cement ratio,the higher the hydration heat release in the early period of cement hydration,but this trend reverses in the late period.There are intersection points of the total hydration heat curve of the cement pastes under the influence of the water-cement ratio,and this law can be observed at both molding temperatures.With the increase in the molding temperature,the age of the second temperature peak on the temperature curve of the cement paste will advance,but the temperature peak will decrease.The higher the molding temperature,the earlier the acceleration period of the cement hydration began,and the larger the hydration heat of the cement in the early stage,but the smaller the total heat in the late period.A subsection function calculation model of the hydration heat,which was based on the existing models,was proposed in order to predict the heat of the hydration of the concrete. 展开更多
关键词 semi-adiabatic calorimetry hydration heat water-cement ratio molding temperature MODELING
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Monocyte to high-density lipoprotein cholesterol ratio as a predictor of the activity of thyroid-associated ophthalmopathy
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作者 Xing-Hong Sun Xiao-Wen Zhang +5 位作者 Chen Han Xin Dou Xue-Ying He Meng-Ru Su Feng Jiang Song-Tao Yuan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2276-2281,共6页
AIM:To evaluate the relationship between monocyte to high-density lipoprotein cholesterol ratio(MHR)and the disease activity of thyroid-associated ophthalmopathy(TAO).METHODS:A total of 87 patients were classified int... AIM:To evaluate the relationship between monocyte to high-density lipoprotein cholesterol ratio(MHR)and the disease activity of thyroid-associated ophthalmopathy(TAO).METHODS:A total of 87 patients were classified into two groups based on clinical activity score(CAS)scoring criteria:high CAS group(n=62,the CAS score was≥3);low CAS group(n=25,the CAS score was<3).In addition,a group of healthy people(n=114)were included to compared the MHR.Proptosis,MHR,average signal intensity ratio(SIR),average lacrimal gland(LG)-SIR,average extraocular muscles(EOM)area from 87 patients with TAO were calculated in magnetic resonance imaging(MRI),and compared between these two groups.Correlation testing was utilized to evaluate the association of parameters among the clinical variables.RESULTS:Patients in high CAS group had a higher proptosis(P=0.041)and MHR(P=0.048).Compared to the healthy group,the MHR in the TAO group was higher(P=0.001).Correlation testing declared that CAS score was strongly associated with proptosis and average SIR,and MHR was positively associated with CAS score,average SIR,and average LG-SIR.The area under the receiver operating characteristic curve(AUC)of MHR was 0.6755.CONCLUSION:MHR,a novel inflammatory biomarker,has a significant association with CAS score and MRI imaging(average SIR and LG-SIR)and it can be a new promising predictor during the active phase of TAO. 展开更多
关键词 thyroid-associated ophthalmopathy monocyte to high-density lipoprotein cholesterol ratio disease activity
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A model for fast electron-driven high-density plasma in the double-cone ignition scheme
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作者 Zhong-Yi Chen Kai-Ge Zhao Ying-Jun Li 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期322-330,共9页
A model for fast electron-driven high-density plasma is proposed to describe the effect of injected fast electrons on the temperature and inner pressure of the plasma in the fast heating process of the double-cone ign... A model for fast electron-driven high-density plasma is proposed to describe the effect of injected fast electrons on the temperature and inner pressure of the plasma in the fast heating process of the double-cone ignition(DCI)scheme.Due to the collision of the two low-density plasmas,the density and volume of the high-density plasma vary.Therefore,the ignition temperature and energy requirement of the high-density plasma vary at different moments,and the required energy for hot electrons to heat the plasma also changes.In practical experiments,the energy input of hot electrons needs to be considered.To reduce the energy input of hot electrons,the optimal moment and the shortest time for injecting hot electrons with minimum energy are analyzed.In this paper,it is proposed to inject hot electrons for a short time to heat the high-density plasma to a relatively high temperature.Then,the alpha particles with the high heating rate and PdV work heat the plasma to the ignition temperature,further reducing the energy required to inject hot electrons.The study of the injection time of fast electrons can reduce the energy requirement of fast electrons for the high-density plasma and increase the probability of successful ignition of the high-density plasma. 展开更多
关键词 fast electrons the high-density plasma alpha particles double-cone ignition scheme the optimal moment the shortest time
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Low Stress TSV Arrays for High-Density Interconnection
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作者 Binbin Jiao Jingping Qiao +8 位作者 Shiqi Jia Ruiwen Liu Xueyong Wei Shichang Yun Yanmei Kong Yuxin Ye Xiangbin Du Lihang Yu Bo Cong 《Engineering》 SCIE EI CAS CSCD 2024年第7期201-208,共8页
In three-dimensional(3D)stacking,the thermal stress of through-silicon via(TSV)has a significant influence on chip performance and reliability,and this problem is exacerbated in high-density TSV arrays.In this study,a... In three-dimensional(3D)stacking,the thermal stress of through-silicon via(TSV)has a significant influence on chip performance and reliability,and this problem is exacerbated in high-density TSV arrays.In this study,a novel hollow tungsten TSV(W-TSV)is presented and developed.The hollow structure provides space for the release of thermal stress.Simulation results showed that the hollow W-TSV structure can release 60.3%of thermal stress within the top 2 lm from the surface,and thermal stress can be decreased to less than 20 MPa in the radial area of 3 lm.The ultra-high-density(1600 TSV∙mm2)TSV array with a size of 640×512,a pitch of 25 lm,and an aspect ratio of 20.3 was fabricated,and the test results demonstrated that the proposed TSV has excellent electrical and reliability performances.The average resistance of the TSV was 1.21 X.The leakage current was 643 pA and the breakdown voltage was greater than 100 V.The resistance change is less than 2%after 100 temperature cycles from40 to 125℃.Raman spectroscopy showed that the maximum stress on the wafer surface caused by the hollow W-TSV was 31.02 MPa,which means that there was no keep-out zone(KOZ)caused by the TSV array.These results indicate that this structure has great potential for applications in large-array photodetectors and 3D integrated circuits. 展开更多
关键词 Thermal stress Through-silicon via(TSV)high-density integration
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Predictive value of intracranial high-density areas in neurological function
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作者 Zhi-Juan Lu Jin-Xing Lai +2 位作者 Jing-Ru Huang Shu-Hua Xie Zhao-Hui Lai 《World Journal of Psychiatry》 SCIE 2024年第7期1080-1086,共7页
BACKGROUND Intracranial high-density areas(HDAs)have attracted considerable attention for predicting clinical outcomes;however,whether HDAs predict worse neurological function and mental health remains controversial a... BACKGROUND Intracranial high-density areas(HDAs)have attracted considerable attention for predicting clinical outcomes;however,whether HDAs predict worse neurological function and mental health remains controversial and unclear,which requires further investigation.In this prospective study,96 patients with acute ischemic stroke(AIS)who accepted endovascular mechanical thrombectomy(EMT)were included.The enrolled patients underwent cranial computed tomography(CT)examination within 24 hours after EMT.Clinical data in terms of National Institutes of Health Stroke Scale(NIHSS),the 3-month modified Rankin Scale(mRS),self-rating depression scale(SDS),and self-rating anxiety scale(SAS)scores were collected and compared between patients with HDAs and non-HDAs and between patients with good and poor clinical prognosis.Compared to patients without HDAs,patients with HDAs presented severe neurological deficits(admission NIHSS score:18±3 vs 19±4),were more likely to have post-stroke disabilities(mRS<3:35%vs 62%),and suffered more severe depression(SDS score:58±16 vs 64±13)and anxiety disorder(SAS score:52±8 vs 59±10).Compared to patients with a good prognosis,patients with a poor prognosis presented severe neurological deficits(admission NIHSS score:17±4 vs 20±3),were more likely to have HDAs on CT images(64%vs 33%),and suffered more severe depression(SDS score:55±19 vs 65±11)and anxiety(SAS score:50±8 vs 58±12).Multivariate analysis revealed that HDAs were independent nega-tive prognostic factors.CONCLUSION In conclusion,HDAs on CT images predicted poor prognosis and severe depressive and anxiety symptoms in patients with AIS who underwent EMT. 展开更多
关键词 Acute ischemic stroke Endovascular mechanical thrombectomy high-density areas Depressive disorder Anxiety disorder
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Dependence of Lower Molding Temperature Limit and Molding Time on Molding Mechanism in Dental Thermoforming
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作者 Mutsumi Takahashi Masatoshi Takeuchi 《Materials Sciences and Applications》 2024年第9期350-357,共8页
Effectiveness and safety of a sports mouthguard depend on its thickness and material, and the thermoforming process affects these. The purpose of this study was to clarify the effects of differences in molding mechani... Effectiveness and safety of a sports mouthguard depend on its thickness and material, and the thermoforming process affects these. The purpose of this study was to clarify the effects of differences in molding mechanisms on the lower molding temperature limit and molding time in dental thermoforming. Ethylene vinyl acetate resin mouthguard sheet and two thermoforming machines;vacuum blower molding machine and vacuum ejector/pressure molding machine were used. The molding pressures for suction molding were −0.018 MPa for vacuum blower molding and −0.090 MPa for vacuum ejector molding, and for pressure molding was set to 0.090 MPa or 0.450 MPa. Based on the manufacturer’s standard molding temperature of 95˚C, the molding temperature was lowered in 2.5˚C increments to determine the lower molding temperature limit at which no molding defects occurred. In order to investigate the difference in molding time depending on the molding mechanism, the duration of molding pressure was adjusted in each molding machine, and the molding time required to obtain a sample without molding defects was measured. The molding time of each molding machine were compared using one-way analysis of variance. The lower molding temperature limit was 90.0˚C for the vacuum blower machine, 77.5˚C for the vacuum ejector machine, 77.5˚C for the pressure molding machine at 0.090 MPa, and 67.5˚C for the pressure molding machine at 0.45 MPa. The lower molding temperature limit was higher for lower absolute values of molding pressure. The molding time was shorter for pressure molding than for suction molding. Significant differences were observed between all conditions except between the pressure molding machine at 0.090 MPa and 0.45 MPa (P < 0.01). A comparison of the differences in lower molding temperature limit and molding time due to molding mechanisms in dental thermoforming revealed that the lower molding temperature limit depends on the molding pressure and that the molding time is longer for suction molding than for pressure molding. 展开更多
关键词 THERMOFORMING Suction molding Pressure molding Lower molding Temperature Limit molding Time
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Non-Darcy Flow in Molding Sands
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作者 Miguel A. Barron-Meza Joan Reyes-Miranda Daniel Flores-Sanchez 《Open Journal of Applied Sciences》 2024年第4期976-982,共7页
Darcy’s law is widely used to describe the flow in porous media in which there is a linear relationship between fluid velocity and pressure gradient. However, it has been found that for high numbers of Reynolds this ... Darcy’s law is widely used to describe the flow in porous media in which there is a linear relationship between fluid velocity and pressure gradient. However, it has been found that for high numbers of Reynolds this law ceases to be valid. In this work, the Ergun equation is employed to consider the non-linearity of air velocity with the pressure gradient in casting sands. The contribution of non-linearity to the total flow in terms of a variable defined as a non-Darcy flow fraction is numerically quantified. In addition, the influence of the shape factor of the sand grains on the non-linear flow fraction is analyzed. It is found that for values of the Reynolds number less or equal than 1, the contribution of non-linearity for spherical particles is around 1.15%. 展开更多
关键词 Darcy’s Law molding Sands Non-Darcy Flow Reynolds Number Shape Factor
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Correlation of Helicobacter pylori infection with high-density lipoprotein cholesterol levels and pulse wave conduction velocity
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作者 Yue-Xi Li Xiao-Qin Liu +1 位作者 Yu-Han Luo Qiao-Li Wang 《Clinical Research Communications》 2024年第4期33-38,共6页
Background:Helicobacter pylori(HP)is associated with several gastrointestinal diseases,including peptic ulcer diseases and gastric cancer,and non-gastrointestinal diseases such as hypertension and Alzheimer's dise... Background:Helicobacter pylori(HP)is associated with several gastrointestinal diseases,including peptic ulcer diseases and gastric cancer,and non-gastrointestinal diseases such as hypertension and Alzheimer's disease.However,the relationship between HP and lipid metabolism and atherosclerosis remains unclear.This study aims to investigate the association between H.pylori infection and high-density lipoprotein cholesterol levels and pulse wave conduction velocity.Methods:This is a report of a cross-sectional study that collected data from 2,827 participants.The data collected included results of life questionnaires,laboratory tests,13C-urea breath test(13C-UBT),and pulse wave conduction velocity test.Based on the results of the 13C-UBT test,the subjects were divided into two groups:the HP-uninfected group(HP−)and the HP-infected group(HP+).The study compared the differences in HDL-C levels and brachial-ankle pulse wave velocity(baPWV)between the two groups.One-way regression analysis was used to identify potential factors affecting HDL-C levels in the study population.Multiple regression equations were presented to analyze whether HP infection was an independent risk factor for abnormal HDL-C metabolism in the population.Results:Univariate analysis demonstrated that high-density lipoprotein cholesterol(HDL-C)levels were significantly lower in the HP+group compared to the HP−group,with a mean difference ofβ=−18.1 mg/dl(95%CI:−19.3 to−17.0,P<0.001).After adjusting for all variables,the HDL-C levels remained lower in the HP+group compared to the HP-group,with a mean difference ofβ=−17.4 mg/dl(95%CI:−18.2 to−16.7,P<0.001).These findings suggest that H.pylori infection is independently associated with abnormal HDL-C metabolism.Additionally,brachial-ankle pulse wave velocity(baPWV)was higher in the HP+group than in the HP−group on both sides.On the right side,the baPWV was 1,713.4±231.4 cm/s in the HP+group compared to 1,542.8±237.5 cm/s in the HP−group(t=−18.30,P<0.001).On the left side,the baPWV was 1,743.7±238.8 cm/s in the HP+group compared to 1,562.8±256.3 cm/s in the HP−group(t=−18.23,P<0.001).These results indicate a significant association between H.pylori infection and increased arterial stiffness,as measured by baPWV.Conclusion:Helicobacter pylori infection is associated with a decrease in high-density lipoprotein cholesterol levels and an increase in pulse wave conduction velocity. 展开更多
关键词 Helicobacter pylori CHOLESTEROL high-density lipoprotein ATHEROSCLEROSIS
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A strategy to obtain a high-density and high-strength zirconia ceramic via ceramic injection molding by the modification of oleic acid 被引量:7
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作者 Jia-xin Wen Tian-bin Zhu +2 位作者 Zhi-peng Xie Wen-bin Cao Wei Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第6期718-725,共8页
Despite its unique high efficiency and good environmental compatibility, the water-soluble binder system still encounters problems achieving a desired sintered part via ceramic injection molding because of the poor co... Despite its unique high efficiency and good environmental compatibility, the water-soluble binder system still encounters problems achieving a desired sintered part via ceramic injection molding because of the poor compatibility and the powder-binder segregation between ceramic powders and binders. The objective of this study was to obtain a sintered part with excellent properties by introducing a small quantity of oleic acid to the surface of zirconia powders before the mixing process. As opposed to many previous investigations that focused only on the rheological behavior and modification mechanism, the sintering behavior and densification process were systematically investigated in this study. With the modified powders, debound parts with a more homogeneous and smaller pore size distribution were fabricated. Also, a higher density and greater flexural strength were achieved in the sintered parts fabricated using the modified powders. 展开更多
关键词 ceramic materials ZIRCONIA injection molding oleic acid SINTERING
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基于 Moldflow 的汽车中控台框架翘曲变形分析及优化 被引量:1
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作者 刘巨保 黄建军 +3 位作者 杨明 李峰 张亮 查翔 《塑料工业》 CAS CSCD 北大核心 2024年第3期83-88,共6页
以某汽车中控台框架为研究对象,测量试模样品发现其翘曲变形量超过了装配要求。通过Moldflow软件模拟了该塑件实际的注塑过程,翘曲变形量的模拟值与实测平均值的最大误差为5.98%,发现该塑件翘曲变形的主要因素为冷却不均和收缩不均。本... 以某汽车中控台框架为研究对象,测量试模样品发现其翘曲变形量超过了装配要求。通过Moldflow软件模拟了该塑件实际的注塑过程,翘曲变形量的模拟值与实测平均值的最大误差为5.98%,发现该塑件翘曲变形的主要因素为冷却不均和收缩不均。本文在原物料中添加质量分数为25%的玻璃纤维以及优化工艺参数后,翘曲变形量的模拟值与初始方案相比降低了86.22%。试模验证表明,优化后的翘曲变形量模拟值与实测平均值的最大误差为4.35%,证明了Moldflow软件模拟分析的准确性。试模后各检测点的最大翘曲变形量降到了1.6 mm以下,较优化之前降低了80%以上,为类似大型复杂注塑件的翘曲变形分析及优化提供了思路。 展开更多
关键词 注塑成型 中控台框架 翘曲变形 模流分析 玻璃纤维
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Conversion of lignin oil and hemicellulose derivative into high-density jet fuel 被引量:4
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作者 Sichao Yang Chengxiang Shi +4 位作者 Zhensheng Shen Lun Pan Zhenfeng Huang Xiangwen Zhang Ji-Jun Zou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期452-460,I0012,共10页
Synthesizing high-density fuel from lignocellulose can not only achieve green and low-carbon development,but also expand the feedstock source of hydrocarbon fuel.Here,we reported a route of producing high-density fuel... Synthesizing high-density fuel from lignocellulose can not only achieve green and low-carbon development,but also expand the feedstock source of hydrocarbon fuel.Here,we reported a route of producing high-density fuel from lignin oil and hemicellulose derivative cyclopentanol through alkylation and hydrodeoxygenation,HY with SiO_(2)/Al_(2)O_(3) molar ratio of 5.3 was screened as the alkylation catalyst in the reaction of model phenolic compounds and mixtures,and the reaction conditions were optimized to achieve conversion of phenolic compounds higher than 87%and selectivity of bicyclic and tricyclic products higher than 99%.Then two phenolic pools simulating the composition of two typic lignin oils were studied to validate the alkylation and analyze the competition mechanism of phenolic compounds in mixture system.Finally,real lignin oil from depolymerized of beech powder was tested,and notably80%of phenolic monomers in the oil were converted into fuel precursor.After hydrodeoxygenation,the alkylated product was converted to fuel blend with a density of 0.91 g/mL at 20℃and a freezing point lower than-60℃,very promising as high density fuel.This work provides a facile and energyefficient way of synthesizing high-performance jet fuel directly from lignocellulosic derivatives,which decreases processing energy consumption and improve the utilization rate of feedstock. 展开更多
关键词 high-density fuel BIOFUEL Lignin oil ALKYLATION HYDRODEOXYGENATION
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QTL mapping for berry shape based on a high-density genetic map constructed by whole-genome resequencing in grape 被引量:2
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作者 Yandi Wu Yong Wang +6 位作者 Xiucai Fan Ying Zhang Jianfu Jiang Lei Sun Qiangwei Luo Feng Sun Chonghuai Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第4期729-742,共14页
Grape berry shape is an important agricultural trait.Clarifying its genetic basis is significant for cultivating grape varieties that meet market demands.However,the current study by forward genetics has not achieved ... Grape berry shape is an important agricultural trait.Clarifying its genetic basis is significant for cultivating grape varieties that meet market demands.However,the current study by forward genetics has not achieved in-depth results.Here,a high-density map was constructed to identify quantitative trait loci(QTLs)for berry shape.A total of 358709 polymorphic SNPs were obtained using whole-genome resequencing(WGS)based on 208 F2 individuals derived from round grape‘E42-6’and oblong grape‘Rizamat’.The 1635.65 cM high-density map was divided into 19 linkage groups with an average distance of 0.37 cM.Using this map,three significant QTLs for fruit shape index(ShI:ratio of berry length to berry width)identified over three years were mapped onto LG4 and LG5,including one stable QTL on Chr5 with the genomic region of 0.47–1.94 Mb.Combining with gene annotation and expression patterns based on RNA-seq data from two contrasting F2 individuals with round and oblong berry(their average ShI was 1.89 and 1.10,respectively)at four developmental stages,four candidate genes were selected from the above QTLs.They were mainly involved in DNA replication,cell wall modification,and phytohormone biosynthesis.Further analysis of RNA-seq data revealed that several important phytohormone synthesis and metabolic pathways were enriched based on differentially expressed genes(DEGs),which was consistent with the results of QTL mapping for genes related to plant hormone biosynthesis in the F2 population.Furthermore,a comparison of plant hormone content showed that there were significant differences in IAA and tZ content between the two contrasting F2 individuals at different developmental stages.Our findings provide molecular insights into the genetic variation in grape berry shape.Stable QTLs and their tightly linked markers offer the possibility of marker-assisted selection to accelerate berry shape breeding. 展开更多
关键词 GRAPE Berry shape Whole-genome resequencing high-density genetic map QTL
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基于Moldex 3D与正交试验的离心泵泵头注塑工艺优化 被引量:2
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作者 李秉辉 张佰城 黄兆阁 《工程塑料应用》 CAS CSCD 北大核心 2024年第1期70-76,共7页
以商用离心泵泵头为研究对象,运用Moldex3D模流分析软件对其注塑成型过程进行了模拟。根据产品的结构特点设置了三种浇口方案,通过对注塑过程的模拟分析选出最佳方案来获得模具设计思路并预测制品成型后可能存在的质量问题。结果表明,... 以商用离心泵泵头为研究对象,运用Moldex3D模流分析软件对其注塑成型过程进行了模拟。根据产品的结构特点设置了三种浇口方案,通过对注塑过程的模拟分析选出最佳方案来获得模具设计思路并预测制品成型后可能存在的质量问题。结果表明,平衡进浇方案的制品具有最好的综合性能,制品的翘曲变形量为1.588 mm,体积收缩率为2.444%。确认最佳浇口方案后,将充填时间(A)、保压时间(B)、冷却时间(C)和模具温度(D)作为实验因素,采用田口法构建五因素四水平的正交试验来获得最佳工艺参数,并使用极差和方差分析对结果进行置信度检测。以翘曲总位移结果为主要权重对象,通过极差分析确定了成型参数的最优组合为A_(1)B_(1)C_(1)D_(1),方差分析则验证了极差分析的结果置信度高于99%。相较于初始方案,制品的翘曲变形量从1.588 mm降低至1.214 mm,降低了23.6%;冷却时间降低至10 s,降低了40%。得知模流分析技术的使用让产品的质量和生产效率都得到了明显的优化,为预测塑件性能、降低生产成本、提高生产效率提供了一种可行的方式。 展开更多
关键词 moldEX3D 正交试验 注塑成型 离心泵 模流分析
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基于Moldflow软件对薄壁件某塑料喷嘴的注塑方案优化研究
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作者 袁志华 符烜赫 袁博 《机械工程师》 2024年第3期14-17,共4页
喷嘴注塑产品的质量和性能很大程度上由注塑方案和工艺参数所决定,不当的注塑方案和工艺参数会导致充填不足、熔接线过多、翘曲变形量大等问题。为了可以减少生产周期,节约生产成本,利用三维软件UG对喷嘴进行建模,基于模流分析软件Moldf... 喷嘴注塑产品的质量和性能很大程度上由注塑方案和工艺参数所决定,不当的注塑方案和工艺参数会导致充填不足、熔接线过多、翘曲变形量大等问题。为了可以减少生产周期,节约生产成本,利用三维软件UG对喷嘴进行建模,基于模流分析软件Moldflow软件对喷嘴注塑产品进行分析和优化,通过比较点浇口和侧浇口两种方案的分析结果,最终确定该产品点浇口的方案更好。并通过设计正交实验,得到优化后的工艺参数。 展开更多
关键词 喷嘴 moldFLOW 模流分析 浇口位置 正交优化
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基于MoldFlow太阳能储能系统下盖成型模拟及应用
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作者 周先保 胡清根 傅海勇 《模具制造》 2024年第2期36-38,共3页
以太阳能储能系统下盖模流分析为例,反复修改流道和浇口截面尺寸与长度以及主流道位置,确定流道尺寸。运用MoldFlow对设计好的流道进行充填分析,以使成型达到流动平衡,并进行冷却、翘曲分析,预测成型缺陷,提出解决措施,为模具设计提供... 以太阳能储能系统下盖模流分析为例,反复修改流道和浇口截面尺寸与长度以及主流道位置,确定流道尺寸。运用MoldFlow对设计好的流道进行充填分析,以使成型达到流动平衡,并进行冷却、翘曲分析,预测成型缺陷,提出解决措施,为模具设计提供浇注系统和冷却系统方案和注射成型工艺参数,并应用于模具设计和实际生产。 展开更多
关键词 太阳能储能系统下盖 流动平衡 成型缺陷
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基于Moldex3D的油漆桶桶盖注塑成型过程分析 被引量:2
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作者 张尧 李章宇 +1 位作者 章金宇 王明伟 《合成树脂及塑料》 CAS 北大核心 2024年第1期62-67,共6页
利用模流分析软件Moldex3D模拟油漆桶桶盖注塑成型过程,研究桶盖模具使用阀式热流道与开式热流道两种不同浇注方案的成型差异,并结合仿真结果设计热流道。通过设计Taguchi DOE实验的因素与水平,优化桶盖产品的注塑工艺参数。结果表明:... 利用模流分析软件Moldex3D模拟油漆桶桶盖注塑成型过程,研究桶盖模具使用阀式热流道与开式热流道两种不同浇注方案的成型差异,并结合仿真结果设计热流道。通过设计Taguchi DOE实验的因素与水平,优化桶盖产品的注塑工艺参数。结果表明:设定工艺参数为熔体温度250℃,保压时间2 s,冷却时间18 s时,产品没有短射、包封等外观质量问题;优化后的注塑工艺参数有效降低了产品的冷却时间。 展开更多
关键词 模流分析软件 moldEX3D 热流道 Taguchi法
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