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Energy Conversion Law of Refuse Gasifi cation/Incineration in Low-Oxygen Plateau Areas—A Case Study of Lhasa,China
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作者 Jun He Yubin Hong +5 位作者 Hong Li Yang Yao Yongjian Xie Xinye Cheng Diyun Chen Lihua Dong 《Transactions of Tianjin University》 EI CAS 2024年第6期498-507,共10页
Combusting refuse for energy production is promising for their treatment and disposal. However, because of geographical constraints, there has not been a stable model for the energy utilization of refuse in low-oxygen... Combusting refuse for energy production is promising for their treatment and disposal. However, because of geographical constraints, there has not been a stable model for the energy utilization of refuse in low-oxygen plateau areas. This paper took Lhasa as an example to conduct gasification and incineration experiments on local representative combustible refuse,and relevant energy conversion laws were investigated. Results showed that under gasification and incineration modes, the energy conversion rate of any component of refuse can reach 75% and 85% in low-oxygen plateau areas at temperatures of 450 and 650 ℃, respectively, which were 5%–10% lower than those in plain areas. The regional distribution of energy conversion of refuse in Lhasa showed that the energy conversion rate under the gasification mode was 3%–5% lower than that of the incineration mode at 450 and 650 ℃. In terms of temperature, the energy conversion rates of refuse were 5%–10% lower at 450 ℃ than those at 650 ℃, but an energy conversion rate of more than 85% can still be achieved. Thus, gasification, incineration, or gasification-assisted secondary incineration at temperatures of at least 450 ℃ is suitable for energy recovery of refuse in low-oxygen plateau areas. 展开更多
关键词 Low-oxygen plateau areas Energy conversion Gasifi cation and incineration REFUSE
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Carbon materials for enhanced photothermal conversion:Preparation and applications on steam generation
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作者 Jiayi Zhu Liu Huang +10 位作者 Feng Bao Guanli Chen Kangjin Song Zheling Wang Hong Xia Jinping Gao Yibing Song Caizhen Zhu Fushen Lu Tingting Zheng Muwei Ji 《Materials Reports(Energy)》 EI 2024年第2期34-44,共11页
Photothermal conversion attracted lots of attention in the past years and sorts of materials were explored to enhance photothermal efficiency.In the past years,solar-driven desalination by photothermal conversion was ... Photothermal conversion attracted lots of attention in the past years and sorts of materials were explored to enhance photothermal efficiency.In the past years,solar-driven desalination by photothermal conversion was proposed to release the shortage of fresh water and then it was considered much more important to prepare photothermal materials on large scales with high performance and low cost.In this review,we summarized the works on carbon-based photothermal materials in the past years,including the preparation as well as their application in steam generation.From these works,we give an outlook on the difficulties and chances of how to design and prepare carbon-based photothermal materials. 展开更多
关键词 Photothermal conversion CARBON COMPOSITES Solar energy Steam generation
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Self-separation ionic liquid catalyst for the highly effective conversion of H_(2)S by α,β-unsaturated carboxylate esters under mild conditions
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作者 Wenjie Xiong Xiaomin Zhang +1 位作者 Xingbang Hu Youting Wu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1440-1448,共9页
The deep-processing utility of pure hydrogen sulfide (H_(2)S) is a significant direction in natural gas chemical industry.Herein,a brand-new strategy of H_(2)S conversion by a,β-unsaturated carboxylate esters into th... The deep-processing utility of pure hydrogen sulfide (H_(2)S) is a significant direction in natural gas chemical industry.Herein,a brand-new strategy of H_(2)S conversion by a,β-unsaturated carboxylate esters into thiols or thioethers using task-specific carboxylate ionic liquids (ILs) as catalyst has been developed,firstly accomplishing the phase separation of product and catalyst without introducing the third component.It can be considered as a cascade reaction in which the product selectivity can be controlled by adjusting the molar ratio of H_(2)S to a,β-unsaturated carboxylate esters.Also,the effects of ILs with different anions and cations,intermittent feeding operations,as well as pressure-time kinetic behaviors on cascade reaction were investigated.Furthermore,the proposed interaction mechanism of H_(2)S conversion using butyl acrylate catalyzed by[Emim][Ac]was revealed by DFT-based theoretical calculation.The approach enables the self-phase separation promotion of catalyst and product and achieves 99%quantitative conversion under mild conditions in the absence of solvent,making the entire process ecologically benign.High-efficiency reaction activity can still be maintained after ten cycles of the catalyst.Therefore,the good results,combined with its simplicity of operation and the high recyclability of the catalyst,make this green method environmentally friendly and cost-effective.It is anticipated that this self-separation method mediated by task-specific ILs will provide a feasible strategy for H_(2)S utilization,which will guide its application on an industrial scale. 展开更多
关键词 Ionic liquid Cascade reaction Self-separation H_(2)S conversion Catalysis
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Rational design of photofunctional dyes BODIPYs/aza-BODIPYs and applications for photocatalysis, photoelectric conversion and thermochromic materials
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作者 Dongxiang Zhang Linxuan Liu +2 位作者 Xin Zhang Jie Lu Xin-Dong Jiang 《Resources Chemicals and Materials》 2024年第2期103-122,共20页
4,4-Difluoro-4-bora-3a,4a-diaza-sindacene (BODIPY) is a sort of photofunctional dye which possesses advantages including strong light-capturing property, high photon-resistance, etc. Meso-N substituted aza-BODIPY is a... 4,4-Difluoro-4-bora-3a,4a-diaza-sindacene (BODIPY) is a sort of photofunctional dye which possesses advantages including strong light-capturing property, high photon-resistance, etc. Meso-N substituted aza-BODIPY is a crucial derivative of BODIPY scaffold that has the favorable optical properties and a significant spectral redshift. The photophysical properties can be tuned by molecular design, and the attenuation path of the excited state energy release of absorbed light energy can be well controlled via structural modifications, enabling tailored application. It has been extensively employed in life medicine fields including fluorescence imaging diagnosis, photodynamic therapy photosensitizer and photothermal therapy reagent and so forth. Extensive research and review have been performed in these areas. However, BODIPYs/aza-BODIPYs have a significant role in energy, catalysis, optoelectronics, photo-responsive materials and other fields. Nevertheless, there are relatively few studies and reviews in these fields on the modification and application based on BODIPY/aza-BODIPY scaffold. Herein, in this review we summarized the application of BODIPY/aza-BODIPY in the aforementioned fields, with the molecular regulation of dye as the foundation and the utilization in the above fields as the objective, in the intention of providing inspiration for the exploration of innovative BODIPY/aza-BODIPY research in the field of light resource conversion and functional materials. 展开更多
关键词 BODIPYs/aza-BODIPYs Photofunctional dyes PHOTOCATALYSIS Photoelectric conversion Thermochromic materials
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Hemogram-derived ratios as prognostic markers for major adverse cardiovascular events in patients with non-ST-segment elevation myocardial infarction
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作者 Emir Bećirović Minela Bećirović +10 位作者 SabinaŠegalo Amir Bećirović Semir Hadžić Kenana Ljuca Emsel Papić Lamija Ferhatbegović Malik Ejubović Amira JagodićEjubović Amila Kovčić ArminŠljivo Emir Begagić 《World Journal of Methodology》 2025年第2期125-136,共12页
BACKGROUND Non-ST segment elevation myocardial infarction(NSTEMI)poses significant challenges in clinical management due to its diverse outcomes.Understanding the prognostic role of hematological parameters and derive... BACKGROUND Non-ST segment elevation myocardial infarction(NSTEMI)poses significant challenges in clinical management due to its diverse outcomes.Understanding the prognostic role of hematological parameters and derived ratios in NSTEMI patients could aid in risk stratification and improve patient care.AIM To evaluate the predictive value of hemogram-derived ratios for major adverse cardiovascular events(MACE)in NSTEMI patients,potentially improving clinical outcomes.METHODS A prospective,observational cohort study was conducted in 2021 at the Internal Medicine Clinic of the University Hospital in Tuzla,Bosnia and Herzegovina.The study included 170 patients with NSTEMI,who were divided into a group with MACE and a control group without MACE.Furthermore,the MACE group was subdivided into lethal and non-lethal groups for prognostic analysis.Alongside hematological parameters,an additional 13 hematological-derived ratios(HDRs)were monitored,and their prognostic role was investigated.RESULTS Hematological parameters did not significantly differ between non-ST segment elevation myocardial infarction(NSTEMI)patients with MACE and a control group at T1 and T2.However,significant disparities emerged in HDRs among NSTEMI patients with lethal and non-lethal outcomes post-MACE.Notably,neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)were elevated in lethal outcomes.Furthermore,C-reactive protein-to-lymphocyte ratio(CRP/Ly)at T1(>4.737)demonstrated predictive value[odds ratio(OR):3.690,P=0.024].Both NLR at T1(>4.076)and T2(>4.667)emerged as significant predictors,with NLR at T2 exhibiting the highest diagnostic performance,as indicated by an area under the curve of 0.811(95%CI:0.727-0.859)and OR of 4.915(95%CI:1.917-12.602,P=0.001),emphasizing its important role as a prognostic marker.CONCLUSION This study highlights the significant prognostic value of hemogram-derived indexes in predicting MACE among NSTEMI patients.During follow-up,NLR,PLR,and CRP/Ly offer important insights into the inflammatory processes underlying cardiovascular events. 展开更多
关键词 Hemogram-derived ratios Prognostic markers Neutrophil-to-lymphocyte ratio Myocardial infarction
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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2
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作者 Qing He Zhen Wang +5 位作者 Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen 《Neural Regeneration Research》 SCIE CAS 2025年第6期1801-1815,共15页
Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders.... Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain. 展开更多
关键词 AQUAPORIN-4 Ascl1 ASTROCYTE cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 REPROGRAMMING
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Diagnostic implications of neutrophil-to-lymphocyte ratio,platelet-tolymphocyte ratio,and systemic immune-inflammatory index for gastric carcinoma
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作者 Huang-Min Wu Xiao-Xuan Ying +1 位作者 Li-Li Lv Jian-Wen Hu 《World Journal of Gastrointestinal Surgery》 2025年第1期139-146,共8页
BACKGROUND The diagnosis of gastric carcinoma(GC)is essential for improving clinical outcomes.However,the biomarkers currently used for GC screening are not ideal.AIM To explore the diagnostic implications of the neut... BACKGROUND The diagnosis of gastric carcinoma(GC)is essential for improving clinical outcomes.However,the biomarkers currently used for GC screening are not ideal.AIM To explore the diagnostic implications of the neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),and systemic immune-inflammatory index(SII)for GC.METHODS The baseline data of 133 patients with GC and 134 patients with precancerous gastric conditions admitted between January 2022 and December 2023 were retrospectively analyzed.The information on peripheral blood platelet,neutrophil,and lymphocyte counts in each patient was collected,and the NLR,PLR,and SII levels of both groups were calculated.Additionally,multivariate logistic regression analysis was conducted,and the diagnostic implications of NLR,PLR,and SII in differentiating patients with precancerous gastric conditions,compared with those with GC,were analyzed through receiver operating characteristic(ROC)curves.RESULTS The data indicated that NLR,PLR,and SII had abnormally increased levels in the patients with GC.Gender and body mass index were risk factors for the occurrence of GC.ROC data revealed that the areas under the curve of three patients with precancerous gastric conditions,who were differentiated from those with GC,were 0.824,0.787,and 0.842,respectively.CONCLUSION NLR,PLR,and SII are all abnormally expressed in GC and have diagnostic implications,especially when used as joint indicators,in distinguishing patients with precancerous gastric conditions from those with GC. 展开更多
关键词 Gastric carcinoma Neutrophil-to-lymphocyte ratio Platelet-to-lymphocyte ratio Precancerous gastric conditions Systemic immune-inflammatory index
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Trends of alkaline phosphatase to prealbumin ratio in patients with hepatitis B linked to hepatocellular carcinoma development
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作者 Wen-Chong Zhen Jing Sun +8 位作者 Xue-Ting Bai Qian Zhang Zi-Han Li Yi-Xin Zhang Rong-Xuan Xu Wei Wu Zhi-Han Yao Chun-Wen Pu Xiao-Feng Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期42-51,共10页
BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality worldwide.Early detection of HCC is crucial,yet challenging.AIM To investigate the role of dyn... BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality worldwide.Early detection of HCC is crucial,yet challenging.AIM To investigate the role of dynamic changes in alkaline phosphatase to prealbumin ratio(APR)in hepatitis B progression to HCC.METHODS Data from 4843 patients with hepatitis B(January 2015 to January 2024)were analyzed.HCC incidence rates in males and females were compared using the log-rank test.Data were evaluated using Kaplan–Meier analysis.The Linear Mixed-Effects Model was applied to track the fluctuation of APR levels over time.Furthermore,Joint Modeling of Longitudinal and Survival data was employed to investigate the temporal relationship between APR and HCC risk.RESULTS The incidence of HCC was higher in males.To ensure the model’s normality assumption,this study applied a logarithmic transformation to APR,yielding ratio.Ratio levels were higher in females(t=5.26,P<0.01).A 1-unit increase in ratio correlated with a 2.005-fold higher risk of HCC in males(95%CI:1.653-2.431)and a 2.273-fold higher risk in females(95%CI:1.620-3.190).CONCLUSION Males are more prone to HCC,while females have higher APR levels.Despite no baseline APR link,rising APR indicates a higher HCC risk. 展开更多
关键词 Alkaline phosphatase to prealbumin ratio Chronic hepatitis B patients Hepatocellular carcinoma Retrospective cohort study Linear Mixed-Effect Mode Joint Modelling of Longitudinal and Survival data
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Established conversions for hybrid entangled states assisted by error-predicted parity-discriminated devices
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作者 Fang-Fang Du Zhi-Guo Fan +2 位作者 Xue-Mei Ren Ming Ma Wen-Yao Liu 《Chinese Physics B》 2025年第1期72-78,共7页
Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This... Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This paper presents two novel schemes,that is,one converts the two-qubit hybrid Knill–Laflamme–Milburn(KLM)entangled state into Bell states and the other one transforms the three-qubit hybrid KLM state into Greenberger–Horne–Zeilinger(GHZ)states assisted by error-predicted and parity-discriminated devices.Importantly,the integration of single photon detectors into the parity-discriminated device enhances predictive capabilities,mitigates potential failures,and facilitates seamless interaction between the nitrogen-vacancy center and photons,so the two protocols operate in an error-predicted way,improving the experimental feasibility.Additionally,our schemes demonstrate robust fidelities(close to 1)and efficiencies,indicating their feasibility with existing technology. 展开更多
关键词 quantum information processing quantum entanglement quantum communication entanglement conversion
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Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing
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作者 LIU Wei JIAO Jinxu +7 位作者 LUO Dusha ZHOU Junjie SHI Lifen WANG Weiwei LI Changqing WANG Peng XIONG Dehua LI Hong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期13-24,共12页
The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum glazing.Under the condition of constant boron content,how the structure and properties vary with B... The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum glazing.Under the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was investigated.In addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were revealed.The results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal expansion.During laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting glass.The absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper ions.The greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser sealing.The shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa. 展开更多
关键词 Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing
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Preoperative serum total bilirubin-albumin ratio as a prognostic indicator in patients with hepatitis-related cirrhosis after splenectomy
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作者 Yi-Fan Chen Yu-Xin Lin +5 位作者 Miao-Miao Chi Da-Qing Li Lin-Tao Chen Yu Zhang Rong-Qian Wu Zhao-Qing Du 《World Journal of Gastrointestinal Surgery》 2025年第1期70-80,共11页
BACKGROUND Splenectomy is an effective yet invasive intervention for alleviating portal pressure in patients with hepatitis cirrhosis.However,the current prognostic indicators for predicting long-term overall survival... BACKGROUND Splenectomy is an effective yet invasive intervention for alleviating portal pressure in patients with hepatitis cirrhosis.However,the current prognostic indicators for predicting long-term overall survival of these patients have several limitations.AIM To assess the potential of preoperative total bilirubin-albumin(B/A)ratio as a prognostic indicator for patients with hepatitis cirrhosis undergoing splenectomy.METHODS A total of 257 patients diagnosed with hepatitis cirrhosis were retrospectively enrolled in the study.Normality test,t-test,Wilcoxon test,χ2 test,or Fisher’s exact test was employed to analyze the intraoperative and postoperative conditions of the patients.Receiver operating characteristic(ROC)curve analysis was utilized to depict the 10-year overall survival rate.RESULTS During the follow-up period,85.99%of the patients survived,with a median survival time of 64.6 months.Multivariate analysis revealed that total serum B/A ratio was an independent risk factor for overall survival(P=0.037).ROC curve analysis demonstrated that a B/A ratio of 0.87 was the optimal cut-off value.Consequently,the patients were categorized into two groups:High B/A group(n=64)and low B/A group(n=193).The median follow-up time for the high B/A group and low B/A group was 56.8 months and 67.2 months,respectively(P=0.045).Notably,the high B/A group exhibited a significantly lower 10-year overall survival compared to the low B/A group(P<0.001).Patients with hepatocellular carcinoma(HCC)had lower overall survival rates.Patients with a high B/A ratio exhibited a lower overall survival than those with a low B/A rate in the overall cohort and the subgroups of patients with HCC or not,early Child-Pugh grade,low albumin-bilirubin grade,and model for end-stage liver disease score≥10(log-rank test,P<0.001 for all).CONCLUSION The B/A ratio can serve as an effective prognostic indicator for overall survival in patients with hepatitis B virusrelated cirrhosis following splenectomy,and a higher B/A ratio may suggest a poorer prognosis. 展开更多
关键词 Serum total bilirubin-albumin ratio Hepatitis-related cirrhosis SPLENECTOMY Prognosis Survival
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Prognostic value of preoperative fibrinogen to albumin ratio in predicting postoperative outcomes in patients with gallbladder cancer
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作者 Peng-Fu Wang Ya-Jian Duan 《World Journal of Gastrointestinal Surgery》 2025年第2期37-44,共8页
BACKGROUND Gallbladder cancer(GBC)is known for its poor prognosis and challenging management.The preoperative fibrinogen to albumin ratio(FAR)has been proposed as a potential prognostic marker for predicting postopera... BACKGROUND Gallbladder cancer(GBC)is known for its poor prognosis and challenging management.The preoperative fibrinogen to albumin ratio(FAR)has been proposed as a potential prognostic marker for predicting postoperative outcomes in GBC patients,but its efficacy and prognostic value remain underexplored.AIM To evaluate the prognostic value of preoperative FAR in GBC outcomes.METHODS This retrospective cohort study included 66 patients who underwent curative surgery for GBC at our institution from January 2018 to January 2022.Preoperative FAR values were obtained within one week prior to surgery.Patients were followed through outpatient visits or telephone interviews,with overall survival(OS)as the primary endpoint.Statistical analyses,including receiver operating characteristic curve analysis and Kaplan-Meier survival estimates,were performed using SPSS software(version 27.0).RESULTS The cohort consisted of 36 male and 30 female patients,with a mean age of 61.81±8.58 years.The optimal FAR cut-off value was determined to be 0.088,with an area under the receiver operating characteristic curve of 0.7899,sensitivity of 68.96%,and specificity of 80.01%.Patients with FAR≤0.088 showed significantly better survival rates(1-year:60.5%,2-year:52.6%,3-year:25.9%)and a median OS of 25.6 months(95%confidence interval:18.8-30.5 months),compared to those with FAR>0.088 who had a median OS of 10.8 months(95%confidence interval:6.3-12.9 months).CONCLUSION Lower preoperative FAR is associated with longer OS in GBC patients,confirming its potential as a valuable prognostic indicator for improving outcome predictions and guiding patient management strategies in gallbladder cancer. 展开更多
关键词 Gallbladder cancer Fibrinogen to albumin ratio Overall survival Prognostic biomarker Surgical outcomes
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Preparation of cerium oxide based environment-friendly chemical conversion coating on magnesium alloy with additives 被引量:10
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作者 陈东初 吴建锋 +2 位作者 梁奕清 叶树林 李文芳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1905-1910,共6页
Ce(SO4)2?H2O2 solution was adopted to prepare a chemical conversion coating on AZ91D magnesium alloy.Additives of Ni(NO3)2 and sodium dodecyl benzene sulfonate were applied to improving the coating formation.SEM,... Ce(SO4)2?H2O2 solution was adopted to prepare a chemical conversion coating on AZ91D magnesium alloy.Additives of Ni(NO3)2 and sodium dodecyl benzene sulfonate were applied to improving the coating formation.SEM,EDS,XRD and GIXD were adopted to study the coating morphology,structure and composition,and the potential change curve in the treating solution was recorded to study the coating growth.Sodium dodecyl benzene sulfonate makes a remarkable improvement in the coating compactness,and shortens the time in the second stage of the coating formation from 5 min to 2 min.Compared to Ni(NO3)2,sodium dodecyl benzene sulfonate makes the more remarkable effect on the corrosion resistance improvement,since it can decrease the current density of corrosion from 7.41×10-5 A/cm2 to 2.20×10-5 A/cm2.The additives of Ni(NO3)2 and sodium dodecyl benzene sulfonate can enhance the Ce content from 18.92% to 22.32% and 25.08% in the coating,respectively.The XRD and GIXD results indicated that all the conversion coating formed in different solutions exhibit amorphous structure. 展开更多
关键词 magnesium alloys surface treatment conversion coating rare earth ADDITIVES
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基于改进Ratio统计量的重尾AR(p)时间序列均值变点检验
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作者 张思 刘叶 金浩 《统计与决策》 CSSCI 北大核心 2024年第2期52-57,共6页
文章提出两个改进的Ratio统计量来研究重尾AR(p)时间序列均值变点检验问题,在原假设下推导了统计量的渐近分布,且在备择假设下证明了其一致性。由于重尾指数未知且难以估计,因此结合Wild Bootstrap重抽样方法来确定渐近分布的临界值;在... 文章提出两个改进的Ratio统计量来研究重尾AR(p)时间序列均值变点检验问题,在原假设下推导了统计量的渐近分布,且在备择假设下证明了其一致性。由于重尾指数未知且难以估计,因此结合Wild Bootstrap重抽样方法来确定渐近分布的临界值;在均值变点存在的情形下,给出了变点位置的一致估计量。数值模拟结果表明:统计量的临界值均不受重尾指数和自回归系数的影响,其经验水平和经验势均取得满意的效果;尤其在原假设下,积分型Ratio统计量的经验水平表现出更好的稳健性,而在备择假设下,最值型Ratio统计量则具备更好的显著性。最后,基于一组股票数据,从实际应用角度进一步阐明所提方法的有效性和可行性。 展开更多
关键词 重尾序列 ratio统计量 均值变点 Wild Bootstrap
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Model-based evaluation on the conversion ratio of ammonium to nitrite in a nitritation process for ammonium-rich wastewater treatment 被引量:4
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作者 LIXiao-ming YANGQi +4 位作者 ZENGGuang-ming A.Cornelius K.H.Rosenwinkel S.Kunst D.Weichgrebe 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期1005-1010,共6页
Modeling for nitritation process was discussed and analyzed quantitatively for the factors that influence nitrite accumulation. The results indicated that pH, inorganic carbon source and Hydraulic Retention Time(HRT) ... Modeling for nitritation process was discussed and analyzed quantitatively for the factors that influence nitrite accumulation. The results indicated that pH, inorganic carbon source and Hydraulic Retention Time(HRT) as well as biomass concentration are the main factors that influenced the conversion ratio of ammonium to nitrite. A constant high pH can lead to a high nitritation rate and results in high conversion ratio on condition that free ammonia inhibition do not happen. In a CSTR system, without pH control, this conversion ratio can be monitored by pH variation in the reactor. The pH goes down far from the inlet level means a strongly nitrite accumulation. High concentration of alkalinity can promoted the conversion ratio by means of accelerating the nitritation rate through providing sufficient inorganic carbon source(carbon dioxide). When inorganic carbon source was depleted, the nitritation process stopped. HRT adjustment could be an efficient way to make the nitritation system run more flexible, which to some extent can meet the requirements of the fluctuant of inlet parameters such as ammonium concentration, pH, and temperature and so on. Biomass concentration is the key point, especially for a CSTR system in steady state, which was normally circumscribed by the characteristics of bacteria and may also affected by aeration mode and can be increased by prolonging the HRT on the condition of no nitrate accumulation when no recirculation available. The higher the biomass concentration is, the better the nitrite accumulation can be obtained. 展开更多
关键词 conversion ratio modeling analysis nitritation process nitrite accumulation
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Automatic IQ Phase Calibration Design in a 2.4GHz Direct Conversion Receiver 被引量:1
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作者 刘瑞峰 李永明 +1 位作者 陈弘毅 王志华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第9期1531-1536,共6页
An automatic IQ phase calibration method implemented in a 2.4GHz direct conversion receiver is proposed. It uses a delay locked loop (DLL) with a proposed quadrature phase detector to greatly reduce the phase error.... An automatic IQ phase calibration method implemented in a 2.4GHz direct conversion receiver is proposed. It uses a delay locked loop (DLL) with a proposed quadrature phase detector to greatly reduce the phase error. The receiver is fabricated in a 0.18μm CMOS process. Measurements show that the IQ phase error can be calibrated within 1°,which satisfies the system requirement. 展开更多
关键词 direct conversion receiver IQ phase calibration CMOS process quadrature phase detector
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Relation between soil matrix potential changes and water conversion ratios during methane hydrate formation processes in loess 被引量:1
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作者 Peng Zhang Qingbai Wu Guanli Jiang Yibin Pu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第2期140-144,共5页
With a new apparatus designed and assembled by ourselves, the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes. The experimental results showed that d... With a new apparatus designed and assembled by ourselves, the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes. The experimental results showed that during two formation processes, the matrix potential changes of the loess all presented a good linear relationship with water conversion ratios. In addition, although it was well known that the secondary gas hydrate formation was easier than the initial, our experimental results showed that the initial hydrate formation efficiency in non-saturated loess was higher than that of the secondary. 展开更多
关键词 hydrate formation non-saturated loess matrix potential water conversion ratio
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Preparation and Performance of Rare Earths Chemical Conversion Film on Magnesium Alloy 被引量:9
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作者 于升学 吕巧艳 +2 位作者 韩婧 张占伟 张倩云 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期397-400,共4页
Golden yellow cerium conversion film was obtained on magnesium alloys surface by immersion method and the preparation parameters were established. The influence of different process parameters on the surface morpholog... Golden yellow cerium conversion film was obtained on magnesium alloys surface by immersion method and the preparation parameters were established. The influence of different process parameters on the surface morphology and performance of the conversion film were analyzed by means of SEM and electrochemical method. Formation dynamics about cerium conversion film on magnesium alloy in solution containing cerium salt and the anti-corrosion behavior of the conversion film in 3.5% NaCl solution were studied by electrochemical method respectively. The results shows that the conversion film is more compact at room temperature when concentration of cerium sulfate is 10 g·L-1 in the solution; the open circuit potential of the magnesium sample moves up to positive direction about 100 mV, the surface of conversion film becomes even and lustrous, and the adhesion intensity of conversion film increases when adding aluminum nitrate into the solution containing cerium salt. The pH value of the solution and immersion time of the sample in the solution also affect the surface morphology and anti-corrosion property of the conversion film. After covered by rare earths conversion film, the anti-corrosion property of magnesium alloy is obviously improved. Rare earth conversion film has self-repairing capability in corrosion medium. 展开更多
关键词 magnesium alloy chemical conversion film corrosion resistance rare earths
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Solar energy conversion on g-C3N4 photocatalyst:Light harvesting,charge separation,and surface kinetics 被引量:11
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作者 Mu Xiao Bin Luo +1 位作者 Songcan Wang Lianzhou Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第4期1111-1123,共13页
Photocatalysis. which utilizes solar energy to trigger chemical reactions, is one of the most desirable solar-energy-conversion approaches. Graphitic carbon nitride (g-C3N4). as an attractive metal-free photocatalys... Photocatalysis. which utilizes solar energy to trigger chemical reactions, is one of the most desirable solar-energy-conversion approaches. Graphitic carbon nitride (g-C3N4). as an attractive metal-free photocatalyst, has drawn worldwide research interest in the area of solar energy conversion due to its easy synthesis, earth-abundant nature, physicochemical stability and visible-light-responsive properties. Over the past ten years, g-C3N4 based photocatalysts have experienced intensive exploration, and great progress has been achieved. However, the solar conversion efficiency is still far from industrial applications due to the wide bandgap, severe charge recombination, and lack of surface active sites. Many strategies have been proposed to enhance the light absorption, reduce the recombination of charge carriers and accelerate the surface kinetics. This work makes a crucial review about the main contributions of various strategies to the light harvesting, charge separation and surface kinetics of g-C3N4 photocatalyst. Furthermore, the evaluation measurements for the enhanced light harvesting, reduced charge recombination and accelerated surface kinetics will be discussed. In addition, this review proposes future trends to enhance the photocatalytic performance of g-C3N4 photocatalyst for the solar energy conversion. 展开更多
关键词 PHOTOCATALYSIS g-C3N4 Light harvesting Charge separation Surface kinetics Solar energy conversion
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Preparation and Corrosion Resistance of Rare Earth Conversion Coatings on AZ91 Magnesium Alloy 被引量:7
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作者 许越 陈湘 +1 位作者 吕祖舜 李英杰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第5期555-558,共4页
The feasibility of forming pollution-free and environmentally benign Ce-based rare earth conversion coatings (short for RECCs) on AZ91 magnesium alloy to enhance corrosion resistance was studied. The effect of optim... The feasibility of forming pollution-free and environmentally benign Ce-based rare earth conversion coatings (short for RECCs) on AZ91 magnesium alloy to enhance corrosion resistance was studied. The effect of optimum processing parameters on corrosion resistance of RECCs, such as density of treating solution, temperature and time of coating formation were discussed. Protective performance of conversion coatings on magnesium alloy was evaluated by moisture/heating test, anodic polarization, etc. The results show that Ce-based RECCs under moisture/heating condition can remain intact, with high coverage and no obvious corrosion phenomenon. Corrosion potential increases and passive phenomenon occurs while current density decreases, therefore Ce-based RECCs can improve corrosion resistance of AZ91 magnesium alloy. The morphology of Ce-based RECCs prepared under optimum process through SEM observation is found to be a few particles coherent to the base coating, and the coating has no cracks and exhibits apparent corrosion resistance during corrosion courses of AZ91 magnesium alloy. 展开更多
关键词 metal materials magnesium alloy rare earth conversion coatings corrosion resistance rare earths
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