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Thermodynamic Correlation Between Surface Carboxyl Configuration and Wettability
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作者 GUO Zhuohuan WANG Dayang 《高等学校化学学报》 北大核心 2026年第1期255-266,共12页
In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using at... In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces. 展开更多
关键词 Polyacrylic acid film Hydrogen bonding Attenuated total reflectance Fourier-transform infrared spectroscopy Quantitative carboxyl configuration Polar component of surface energy
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High‑density genetic mapping enhances genomic selection accuracy for complex traits in Populus
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作者 Chenchen Guo Tongming Yin Suyun Wei 《Journal of Forestry Research》 2026年第2期290-304,共15页
Populus species,important economic species combining rapid growth with broad ecological adaptability,play a critical role in sustainable forestry and bioenergy production.In this study,we performed whole-genome resequ... Populus species,important economic species combining rapid growth with broad ecological adaptability,play a critical role in sustainable forestry and bioenergy production.In this study,we performed whole-genome resequencing of 707 individuals from a full-sib family to develop comprehensive single nucleotide polymorphism(SNP)markers and constructed a high-density genetic linkage map of 19 linkage groups.The total genetic length of the map reached 3623.65 cM with an average marker interval of 0.34 cM.By integrating multidimensional phenotypic data,89 quantitative trait loci(QTL)associated with growth,wood physical and chemical properties,disease resistance,and leaf morphology traits were identified,with logarithm of odds(LOD)scores ranging from 3.13 to 21.72 Notably,pleiotropic analysis revealed significant colocaliza and phenotypic variance explained between 1.7% and 11.6%.-tion hotspots on chromosomes LG1,LG5,LG6,LG8,and LG14,with epistatic interaction network analysis confirming genetic basis of coordinated regulation across multiple traits.Functional annotation of 207 candidate genes showed that R2R3-MYB and bHLH transcription factors and pyruvate kinase-encoding genes were significantly enriched,suggesting crucial roles in lignin biosynthesis and carbon metabolic pathways.Allelic effect analysis indicated that the frequency of favorable alleles associated with target traits ranged from 0.20 to 0.55.Incorporation of QTL-derived favorable alleles as random effects into Bayesian-based genomic selection models led to an increase in prediction accuracy ranging from 1% to 21%,with Bayesian ridge regression as the best predictive model.This study provides valuable genomic resources and genetic insights for deciphering complex trait architecture and advancing molecular breeding in poplar. 展开更多
关键词 Genomic selection Genetic map Quantitative trait loci GROWTH Disease resistance
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Sonazoid-contrast-enhanced ultrasound for the histological diagnosis of hepatocellular carcinoma
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作者 Ruo-Bing Liu Jun-Yi Xin +1 位作者 Zhe Huang Kai-Yan Li 《World Journal of Gastrointestinal Oncology》 2026年第1期122-134,共13页
BACKGROUND The treatment technology of liver cancer is progressing.In addition to traditional surgical resection,combined therapies of immunotherapy based on immune checkpoint inhibitors,chemotherapy,and transcatheter... BACKGROUND The treatment technology of liver cancer is progressing.In addition to traditional surgical resection,combined therapies of immunotherapy based on immune checkpoint inhibitors,chemotherapy,and transcatheter arterial chemoembolization for hepatocellular carcinoma are more and more widely used.Accurate preoperative diagnosis of liver cancer will provide important information for comprehensive treatment and prognosis evaluation of liver cancer.Sonazoidcontrast-enhanced ultrasound is not only helpful for the qualitative diagnosis of liver lesions,but also has great potential in the diagnosis of histological differentiation of liver cancer.AIM To assess the differentiation of hepatocellular carcinoma(HCC)by utilizing the parameters and imaging features of Sonazoid-contrast-enhanced ultrasound(CEUS).METHODS A retrospective analysis was conducted on the CEUS data of 239 lesions through case-control study.These patients received Sonazoid-CEUS within one week before surgery and were confirmed as HCC by postoperative pathology.Within the cases,patients were further categorized into well-differentiated and poorlydifferentiated group.Time-intensity curves of the region of interest in both arterial and Kupffer phases were generated,allowing for the acquisition of quantitative parameters to assess the diagnostic efficacy in distinguishing lesions between these two groups and determining an appropriate cut-off value.RESULTS Univariate analysis showed that the absolute value of enhancement intensity(EIAV),intensity ratio(IR)and intensity difference(ID)in Kupffer phase were statistically different between the groups with different degree(P=0.015,P=0.000,P=0.000).The sensitivity and specificity were 40.2%,82.4%,80.4% and 78.1%,86.9% and 74.5%,respectively,for differentiating HCC lesions with EIAV≥56.384 dB,IR≥1.215 and ID≥9.184 dB.The area under the receiver operating characteristic curve were 0.590,0.877,0.815.There was no significant difference in the parameters of arterial phase,including peak time,initial growth time,rise time and the absolute value of peak intensity of lesions between the two groups(P>0.05).Multivariate analysis showed that the level of alphafetoprotein(AFP)and IR were risk factors for poor differentiation(P=0.001).CONCLUSION Among the parameters of Sonazoid-CEUS,IR in Kupffer phase exhibits superior diagnostic efficacy with high sensitivity and specificity in the diagnose of pathological differentiation of HCC.Combined with preoperative AFP level,a more accurate diagnosis will be obtained.Compared with portal vein phase,Kupffer phase showed the ability to identify HCC lesions more sensitive.These findings hold significant guiding implications and reference value for clinical practice. 展开更多
关键词 Contrast-enhanced ultrasound Hepatocellular carcinoma Quantitative parameters Kupffer phase Pathological differentiation
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Natural variations in MdBPM2/MdRGLG3-MdNAC83 network controlling the quantitative segregation of apple fruit storability
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作者 Bei Wu Fei Shen +5 位作者 Ziying Zhou Wenhui Ren Yi Wang Ting Wu Zhenhai Han Xinzhong Zhang 《Journal of Integrative Plant Biology》 2026年第1期169-190,共22页
Dissecting quantitative traits into Mendelian factors is a great challenge in genetics.Apple fruit storability is a complex trait controlled by multi-genes with unequal effects.We previously identified62 quantitative ... Dissecting quantitative traits into Mendelian factors is a great challenge in genetics.Apple fruit storability is a complex trait controlled by multi-genes with unequal effects.We previously identified62 quantitative trait loci(QTLs)associated with apple fruit storability and genomics-assisted prediction(GAP)models were trained using 56 QTLbased markers.Here,three candidate genes,Md NAC83,Md BPM2,and Md RGLG3,were screened from the regions of QTLs with large G'value and large genetic effects.Both a 216-bp deletion and an SNP934 T/C at the promoter of Md NAC83 were associated with higher Md NAC83expression but an SNP388 G/A at the coding region significantly reduced the activity to activate the expression of the target genes Md ACO1,Md MANA3,and Md XTH28.Md BPM2 and Md RGLG3 participated in the ubiquitination of Md NAC83.SNP657 T/A of Md BPM2 and SNP167C/G of Md RGLG3 caused a reduction in the activity to ubiquitinate Md NAC83.By the addition of functional markers to the Geno Baits SNP array,the prediction accuracy of the updated GAP models increased to 0.7723/0.6231 and 0.5639/0.5345 for flesh firmness/crispness at harvest and flesh firmness/crispness retainability,respectively.The variation network involving eight simple Mendelian variations in six genes helps to gain insight into the molecular quantitative genetics,to improve breeding strategy,and to provide targets for future genome editing. 展开更多
关键词 fruit storability genetic variation Malus domestica Borkh protein ubiquitination quantitative trait
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Definition of critical skin defect and concepts of structural and functional repairs:Proposal and verification in a rat model
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作者 Cong Sun Weihong Guo +4 位作者 Fang Liang Rabia Javed Weijian Hou Xingdong Zhang Qiang Ao 《Animal Models and Experimental Medicine》 2026年第1期168-182,共15页
Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult t... Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult to compare their research results.Methods:The time for wound closure was evaluated and recorded through gross observation.The regression equation between the healing time and the diameter of skin defect was established,which can be used to predict the healing time for a certain skin defect size in rats.Histochemical and immunohistochemical staining was used to observe the regeneration and reconstruction of skin appendages,and the functional skin repair was quantitatively scored.Results:The critical-size defect of rats was determined based on the maximum capacity of structural skin repair,and the functional skin repair was quantitatively scored based on the regeneration and reconstruction of skin appendages.The allowable range of critical-size skin defect of SD rats lies between 45 and 50 mm in diameter.The concept of structural repair and the category of functional repair of injured skin are put forward.The regression equation between the structural skin healing time and defect diameters is established.Conclusion:The allowable range of skin critical-size defect of SD rats lies between 45 and 50 mm in diameter.The regression equation between the structural skin healing time and defect diameters can be used to predict the healing time for a certain skin defect size in rats. 展开更多
关键词 critical defect functional repair quantitative evaluation skin defect structural repair
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Quantitative indices for train running performance and post-seismic traffic capacity assessment of high-speed railway bridges under random site conditions
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作者 Wangbao ZHOU Jieyu XU +4 位作者 Yu HOU Lizhong JIANG Hao LIU Yuhao WU Donghang PENG 《Science China(Technological Sciences)》 2026年第3期348-365,共18页
Under earthquake action, different site conditions have a notable impact on the dynamic response of high-speed railway bridges after earthquakes, which in turn poses a threat to the running stability of trains in the ... Under earthquake action, different site conditions have a notable impact on the dynamic response of high-speed railway bridges after earthquakes, which in turn poses a threat to the running stability of trains in the post-earthquake period. Therefore, establishing a calculation method for the post-earthquake train speed threshold that considers the influence of different site characteristics is of great engineering significance. Taking the CRTS Ⅲ slab track as the research object, this study is based on the track irregularity root mean square rate(TRR), which the authors proposed earlier to quantify the track regularity level. Using the nonlinear least squares fitting method, the mapping relationship between the TRR and the postearthquake train running performance indicators on bridges is established. Furthermore, the influence of laws governing site categories and train speeds on post-earthquake train running performance on bridges is analyzed, and a train speed threshold for bridges based on running performance under random site conditions is proposed. The research results indicate that all train running performance indicators increase significantly with the increase of train operating speed;different site categories have a significant impact on post-earthquake track residual deformation and train running stability. The greater the amplitude of postearthquake track alignment residual deformation, the lower the threshold for the stable running speed of trains after the earthquake, with the speed threshold decreasing by up to 20%. The research outcomes can provide technical references for the post-earthquake safe operation and maintenance of high-speed railway bridges under complex site conditions, as well as the formulation of targeted train speed control schemes. 展开更多
关键词 high-speed railway track regularity quantitative indicators site conditions train running performance
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A NIR and ratiometric fluorescent probe for quantitative detection of SO_(2) derivatives in Chinese medicinal materials and bioimaging in vivo
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作者 Meitong Wu Ke Wu +7 位作者 Shumin Feng Li Xu Mi Lei Jianmei Chen Shuang Li Mian Qin Dahui Liu Guoqiang Feng 《Chinese Chemical Letters》 2026年第1期434-439,共6页
Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the q... Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the quality of these medicinal materials and contributing to various health issues.Due to a lack of effective monitoring and imaging tools,the physiological effects of excessive SO_(2) residues in traditional Chinese medicine remain unclear.Therefore,developing a rapid and effective tool for detecting SO_(2) is crucial for understanding its metabolic pathways and effects in vivo.In this study,we developed a near infrared(NIR) and ratiometric fluorescent probe,NIR-RS,which exhibits high sensitivity,selectivity,and rapid response for SO_(2) detection.Notably,NIR-RS accurately quantifies SO_(2) contents in Pinelliae rhizoma(P.rhizoma) samples,with recovery rates from 98.46 % to 102.40 %,and relative standard deviations(RSDs)< 5.0 %.For bioimaging applications,NIR-RS has low cytotoxicity and good mitochondrial-targeting ability,making it suitable for imaging exogenous and endogenous SO_(2) in mitochondria.Additionally,NIR-RS was successfully applied to image SO_(2) content of P.rhizoma samples within cells,revealing that high SO_(2) residue elevated mitochondria adenosine triphosphate(ATP) content,these findings reveal that P.rhizoma with excessive SO_(2) can affect the organism's growth mechanisms through alterations in ATP pathways.In vivo,SO_(2) was found to predominantly accumulate in the liver following gavage with P.rhizoma solution,with accumulation levels increasing in proportion to SO_(2) residue concentration.High SO_(2) concentrations in P.rhizoma can cause pulmonary fibrosis and gastric mucosal damage.This work provides a valuable tool for regulating SO_(2) content in P.rhizoma and may help researcher better understand the metabolism of SO_(2) derivatives and explore their physiological roles in biological systems. 展开更多
关键词 Fluorescent probe SO_(2)derivatives metabolism Quantitative analysis Pinelliae rhizoma Fluorescent imaging
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QTL-Seq Identifies Genomic Regions Associated with Resistance to Bipolaris oryzae and Their Association with Defense Related Enzyme Activity in Rice
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作者 Jagjeet Singh LORE Sanjay KUMAR +4 位作者 Dharminder BHATIA Mandeep Singh HUNJAN Rishabh MAHESHWARI Dayananda Veeriah Patil Jyoti JAIN 《Rice science》 2026年第1期15-20,I0028-I0033,共12页
Brown spot(BS)of rice,caused by Bipolaris oryzae,is a serious concern that not only causes quantitative losses but also affects grain quality.To manage this disease,the use of resistant genetic sources and QTLs is an ... Brown spot(BS)of rice,caused by Bipolaris oryzae,is a serious concern that not only causes quantitative losses but also affects grain quality.To manage this disease,the use of resistant genetic sources and QTLs is an eco-friendly and economical option.In the current study,F_(3) progenies derived from a cross of susceptible parent PMS-18-B(PAU 10845-1-1-1-1)×resistant parent RP Path 77(RP patho-17)were used to identify potential QTLs linked to BS resistance and to associate this resistance with a temporal spike in defense-related enzymes. 展开更多
关键词 bipolaris oryzae temporal spik RESISTANCE defense related enzymes bipolaris oryzaeis identify potential qtls resistant genetic sources quantitative trait loci
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Magnetic resonance imaging tracing of superparamagnetic iron oxide nanoparticle-labeled mesenchymal stromal cells for repairing spinal cord injury
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作者 Xiaoli Mai Yuanyuan Xie +12 位作者 Zhichong Wu Junting Zou Jiacheng Du Yunpeng Shen Hao Liu Bo Chen Mengxia Zhu Jiong Shi Yang Chen Bing Zhang Zezhang Zhu Bin Wang Ning Gu 《Neural Regeneration Research》 2026年第5期2031-2039,共9页
Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu... Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury. 展开更多
关键词 acute spinal cord injury diffusion tensor imaging dynamic migration mesenchymal stromal cells neural function neuronal regeneration quantitative susceptibility mapping repairability ruicun superparamagnetic iron oxide nanoparticle
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基于recA基因的qPCR与RAA-LFD检测鳗败血假单胞菌方法的建立与应用
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作者 王一霖 艾明齐 +7 位作者 蒋奇滨 彭焜 周柯宇 樊威 欧阳萍 陈德芳 黄小丽 耿毅 《南方水产科学》 北大核心 2025年第2期138-148,共11页
为实现鳗败血假单胞菌(Pseudomonas anguilliseptica,PA)早期感染的快速诊断,基于recA基因建立了2种检测方法:SYBR Green I实时荧光定量PCR(SYBR Green I real-time quantitative PCR)和重组酶介导等温扩增结合侧流层析试纸条(Recombina... 为实现鳗败血假单胞菌(Pseudomonas anguilliseptica,PA)早期感染的快速诊断,基于recA基因建立了2种检测方法:SYBR Green I实时荧光定量PCR(SYBR Green I real-time quantitative PCR)和重组酶介导等温扩增结合侧流层析试纸条(Recombinase-mediated isothermal amplification combined with lateral flow dipstick,RAA-LFD)。以PA的管家基因recA为靶标,设计筛选出1对qPCR特异性引物、1对RAA特异性引物和RAA探针,并通过同源重组构建标准品质粒pUC18-recA,以建立2种检测方法。将所建立的方法应用于PA感染的大口黑鲈(Micropterus salmoides)组织样本检测,并测定PA载量。结果表明,建立的qPCR方法最低DNA检测浓度为2.816×10^(2)拷贝·μL^(-1),模板量与Ct值在构建的标准曲线中呈现良好的线性关系(r^(2)=0.9992),且具有较强的特异性和较高的稳定性;RAA-LFD方法的最低DNA检测浓度为2.816×10^(4)拷贝·μL^(-1),检测时间最快可达15 min,显色较为稳定且特异性强。应用结果显示,qPCR和RAALFD方法的阳性样本检出率分别为87.50%和85.00%,较普通PCR方法明显提高;其中,qPCR方法可准确测定PA感染宿主组织中的菌体载量,肾中的载量最高,达3.533×10^(7)拷贝·ng^(-1)。建立的2种方法特异性均较好,其中qPCR方法灵敏性更高,RAA-LFD方法则时效性更强,均可用于PA早期感染的检测,且qPCR方法还可对感染宿主体内的菌体载量进行定量分析。 展开更多
关键词 鳗败血假单胞菌 大口黑鲈 SYBR Green I real-time quantitative PCR RAA-LFD 菌体载量
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RPSR1,a major quantitative trait locus for Pythium stalk rot resistance in maize 被引量:2
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作者 Shengfeng He Junbin Chen +4 位作者 Chuang Liu Dandan Liu Lei Wang Canxing Duan Wangsheng Zhu 《The Crop Journal》 2025年第1期51-61,共11页
Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant h... Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant hybrids breeding.In this study,a major QTL,Resistance to Pythium stalk rot 1(RPSR1),was identified from a set of recombinant inbred lines derived from MS71 and POP.Using a recombinant progeny testing strategy,RPSR1 was fine-mapped in a 472 kb interval.Through candidate gene expression,gene knock-down and knock-out studies,a leucine-rich repeat receptor-like kinase gene,PEP RECEPTOR 2(ZmPEPR2),was assigned as a PSR resistance gene.These results provide insights into the genetic architecture of resistance to PSR in maize,which should facilitate breeding maize for resistance to stalk rot. 展开更多
关键词 MAIZE Pythium stalk rot Quantitative trait loci(QTL) LRR-RLK ZmPEPR2
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Operando quantitatively analyses of polarizations in all-vanadium flow batteries 被引量:1
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作者 Zhenyu Wang Jing Sun +8 位作者 Jiadong Shen Zixiao Guo Xiaosa Xu Jin Li Jiayou Ren Yiju Li Tianshuai Wang Xinzhuang Fan Tianshou Zhao 《Journal of Energy Chemistry》 2025年第6期178-184,I0005,共8页
All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential ... All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments. 展开更多
关键词 Vanadium flow battery Quantitative analysis Polarization Oxygen functional groups BISMUTH
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Quantitative insight into fracture distribution during supercritical CO_(2)fracturing in tight sandstone formation 被引量:1
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作者 Bing Yang Hai Huang +5 位作者 Qian-Qian Ren Hai-Zhu Wang Bin Wang Jun Ni Yong Zheng Wen-Tong Zhang 《Petroleum Science》 2025年第4期1670-1685,共16页
Supercritical CO_(2)(SC-CO_(2))fracturing stands out a promising waterless stimulation technique in the development of unconventional resources.While numerous studies have delved into the inducedfracture mechanism of ... Supercritical CO_(2)(SC-CO_(2))fracturing stands out a promising waterless stimulation technique in the development of unconventional resources.While numerous studies have delved into the inducedfracture mechanism of SC-CO_(2),the small scale of rock samples and synthetic materials used in many studies have limited a comprehensive understanding of fracture propagation in unconventional formations.In this study,cubic tight sandstone samples with dimensions of 300 mm were employed to conduct SC-CO_(2)fractu ring experiments under true-triaxial stre ss conditions.The spatial morphology and quantitative attributes of fracture induced by water and SC-CO_(2)fracturing were compared,while the impact of in-situ stress on fracture propagation was also investigated.The results indicate that the SCCO_(2)fracturing takes approximately ten times longer than water fracturing.Furthermore,under identical stress condition,the breakdown pressure(BP)for SC-CO_(2)fracturing is nearly 25%lower than that for water fracturing.A quantitative analysis of fracture morphology reveals that water fracturing typically produces relatively simple fracture pattern,with the primary fracture distribution predominantly controlled by bedding planes.In contrast,SC-CO_(2)fracturing results in a more complex fracture morphology.As the differential of horizontal principal stress increases,the BP for SC-CO_(2)fractured rock exhibits a downward trend,and the induced fracture morphology becomes more simplified.Moreover,the presence of abnormal in-situ stress leads to a further increase in the BP for SC-CO_(2)fracturing,simultaneously enhancing the development of a more conductive fracture network.These findings provide critical insights into the efficiency and behavior of SC-CO_(2)fracturing in comparison to traditional water-based fracturing,offering valuable implication for its potential applications in unconventional reservoirs. 展开更多
关键词 Supercritical CO_(2) True-triaxial fracturing Tight sandstone Fracture propagation Quantitative analysis
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Quantitative detection of trace nanoplastics (down to 50 nm) via surface-enhanced Raman scattering based on the multiplex-feature coffee ring 被引量:1
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作者 Xinao Lin Fengcai Lei +5 位作者 Xiu Liang Yang Jiao Xiaofei Zhao Zhen Li Chao Zhang Jing Yu 《Opto-Electronic Advances》 2025年第6期27-39,共13页
Quantitative detection of trace small-sized nanoplastics(<100 nm)remains a significant challenge in surface-enhanced Raman scattering(SERS).To tackle this issue,we developed a hydrophobic CuO@Ag nanowire substrate ... Quantitative detection of trace small-sized nanoplastics(<100 nm)remains a significant challenge in surface-enhanced Raman scattering(SERS).To tackle this issue,we developed a hydrophobic CuO@Ag nanowire substrate and introduced a multiplex-feature analysis strategy based on the coffee ring effect.This substrate not only offers high Raman enhancement but also exhibits a high probability of detection(POD),enabling rapid and accurate identification of 50 nm polystyrene nanoplastics over a broad concentration range(1–10−10 wt%).Importantly,experimental results reveal a strong correlation between the coffee ring formation and the concentration of nanoplastic dispersion.By incorporating Raman signal intensity,coffee ring diameter,and POD as combined features,we established a machine learning-based mapping between nanoplastic concentration and coffee ring characteristics,allowing precise predictions of dispersion concentration.The mean squared error of these predictions is remarkably low,ranging from 0.21 to 0.54,representing a 19 fold improvement in accuracy compared to traditional linear regression-based methods.This strategy effectively integrates SERS with wettability modification techniques,ensuring high sensitivity and fingerprinting capabilities,while addressing the limitations of Raman signal intensity in accurately reflecting concentration changes at ultra-low levels,providing a new idea for precise SERS measurements of nanoplastics. 展开更多
关键词 quantitative detection of trace nanoplastics surface-enhanced Raman scattering coffee ring multiplexfeature analysis machine learning
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Experimental and modeling investigation of zero net liquid flow in hilly terrain pipeline 被引量:1
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作者 Bo Huang Qiang Xu +4 位作者 Ying-Jie Chang Ye-Qi Cao Hai-Yang Yu Yu-Wen Li Lie-Jin Guo 《Petroleum Science》 2025年第5期2183-2202,共20页
Hilly terrain pipeline is a common form of pipeline in oil and gas storage and transportation industry.Due to the hilly terrain influence, the liquid at the elbow of the gathering pipeline is easy to flow back and acc... Hilly terrain pipeline is a common form of pipeline in oil and gas storage and transportation industry.Due to the hilly terrain influence, the liquid at the elbow of the gathering pipeline is easy to flow back and accumulate to form slug flow, so it is necessary to remove the accumulated liquid by gas purging. In this paper, experiment is carried out in hilly terrain pipelines. Three flow patterns of stratified flow, slug flow and stratified entrained flow are observed. The process of gas purging accumulated liquid is divided into four stages, namely liquid accumulation, liquid rising, continuous outflow and tail outflow. At the same time, the flow pattern maps of each stage are drawn. The pressure drop signal is analyzed in time domain and frequency domain, and the contour map of pressure drop distribution is drawn. It is found that the ratio of range to average value can well distinguish the occurrence range of each flow pattern.Based on visualization, the transition process of slug flow to stratified flow and stratified entrained flow is studied, and the transition boundary prediction model is established. An image processing method is proposed to convert the image signal into a similarity curve, and PSD analysis is performed to calculate the slug frequency. The normal distribution is used to fit the slug frequency, and the predicted correlation is in good agreement with the experimental data. 展开更多
关键词 Hilly terrain pipeline Zero net liquid flow Slug flow Flow pattern transition Quantitative image processing
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Combining label-free quantitative proteomics and 2D-DIGE to identify the potential targets of Sini Decoction acting on myocardial infarction 被引量:1
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作者 Fei Feng Weiyue Zhang +4 位作者 Yan Cao Diya Lv Yifeng Chai Dandan Guo Xiaofei Chen 《Chinese Journal of Natural Medicines》 2025年第8期1016-1024,共9页
Sini Decoction(SNT)is a traditional formula recognized for its efficacy in warming the spleen and stomach and dispersing cold.However,elucidating the mechanism of action of SNT remains challenging due to its complex m... Sini Decoction(SNT)is a traditional formula recognized for its efficacy in warming the spleen and stomach and dispersing cold.However,elucidating the mechanism of action of SNT remains challenging due to its complex multiple components.This study utilized a synergistic approach combining two-dimensional fluorescence difference in gel electrophoresis(2D-DIGE)-based drug affinity responsive target stability(DARTS)with label-free quantitative proteomics techniques to identify the direct and indirect protein targets of SNT in myocardial infarction.The analysis identified 590 proteins,with 30 proteins showing significant upregulation and 51 proteins showing downregulation when comparing the SNT group with the model group.Through the integration of 2D-DIGE DARTS with proteomics data and pharmacological assessments,the findings indicate that protein disulfide-isomerase A3(PDIA3)may serve as a potential protein target through which SNT provides protective effects on myocardial cells during myocardial infarction. 展开更多
关键词 Sini Decoction Myocardial infarction Drug affinity response target stability Label-free quantitative proteomics
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An economical and flexible chip using surface-enhanced infrared absorption spectroscopy for pharmaceutical detection:Combining qualitative analysis and quantitative detection 被引量:1
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作者 Jikai Wang Pengfei Zeng +3 位作者 Haitao Xie Suisui He Xilin Xiao Cuiyun Yu 《Journal of Pharmaceutical Analysis》 2025年第2期474-476,共3页
Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challeng... Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challenge emerges from the misalignment between the mid-IR light wavelength range and molecular dimensions,culminating in a constrained absorption cross-section and diminished vibrational absorption coefficients(Supplementary data). 展开更多
关键词 pharmaceutical detection quantitative detection structural analysis surface enhanced infrared absorption spectroscopy qualitative analysis chemical signatures infrared spectroscopy molecular vibrational spectroscopyfurnishes
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Prognostic value of quantitative flow ratio measured immediately after percutaneous coronary intervention for chronic total occlusion 被引量:1
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作者 Zheng QIAO Zhang-Yu LIN +10 位作者 Qian-Qian LIU Rui ZHANG Chang-Dong GUAN Sheng YUAN Tong-Qiang ZOU Xiao-Hui BIAN Li-Hua XIE Cheng-Gang ZHU Hao-Yu WANG Guo-Feng GAO Ke-Fei DOU 《Journal of Geriatric Cardiology》 2025年第4期433-442,共10页
BACKGROUND The clinical impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) in patients treated with PCI for chronic total occlusion (CTO) was still undetermined.METHODS All CTO vesse... BACKGROUND The clinical impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) in patients treated with PCI for chronic total occlusion (CTO) was still undetermined.METHODS All CTO vessels treated with successful anatomical PCI in patients from PANDA Ⅲ trial were retrospectively measured for postPCI QFR.The primary outcome was 2-year vessel-oriented composite endpoints (VOCEs,composite of target vessel-related cardiac death,target vessel-related myocardial infarction,and ischemia-driven target vessel revascularization).Receiver operator characteristic curve analysis was conducted to identify optimal cutoff value of post-PCI QFR for predicting the 2-year VOCEs,and all vessels were stratified by this optimal cutoff value.Cox proportional hazards models were employed to calculate the hazard ratio (HR) with 95% CI.RESULTS Among 428 CTO vessels treated with PCI,353 vessels (82.5%) were analyzable for post-PCI QFR.31 VOCEs (8.7%) occurred at 2 years.Mean value of post-PCI QFR was 0.92±0.13.Receiver operator characteristic curve analysis shown the optimal cutoff value of post-PCI QFR for predicting 2-year VOCEs was 0.91.The incidence of 2-year VOCEs in the vessel with post-PCI QFR<0.91 (n=91) was significantly higher compared with the vessels with post-PCI QFR≥0.91 (n=262)(22.0%vs.4.2%,HR=4.98,95%CI:2.32–10.70).CONCLUSIONS Higher post-PCI QFR values were associated with improved prognosis in the PCI practice for coronary CTO.Achieving functionally optimal PCI results (post-PCI QFR value≥0.91) tends to get better prognosis for patients with CTO lesions. 展开更多
关键词 chronic total occlusion cto Quantitative Flow Ratio Vessel Oriented Composite Endpoints Chronic Total Occlusion Prognostic Value panda iii Post Percutaneous Coronary Intervention
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Attention Eraser and Quantitative Measures for Automated Bone Age Assessment
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作者 Liuqiang Shu Lei Yu 《Computers, Materials & Continua》 SCIE EI 2025年第1期627-644,共18页
Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological age.To predict bone age more accurately based on radiographs,and for the left-hand X-ray im... Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological age.To predict bone age more accurately based on radiographs,and for the left-hand X-ray images of different races model can have better adaptability,we propose a neural network in parallel with the quantitative features from the left-hand bone measurements for BAA.In this study,a lightweight feature extractor(LFE)is designed to obtain the featuremaps fromradiographs,and amodule called attention erasermodule(AEM)is proposed to capture the fine-grained features.Meanwhile,the dimensional information of the metacarpal parts in the radiographs is measured to enhance the model’s generalization capability across images fromdifferent races.Ourmodel is trained and validated on the RSNA,RHPE,and digital hand atlas datasets,which include images from various racial groups.The model achieves a mean absolute error(MAE)of 4.42 months on the RSNA dataset and 15.98 months on the RHPE dataset.Compared to ResNet50,InceptionV3,and several state-of-the-art methods,our proposed method shows statistically significant improvements(p<0.05),with a reduction in MAE by 0.2±0.02 years across different racial datasets.Furthermore,t-tests on the features also confirm the statistical significance of our approach(p<0.05). 展开更多
关键词 Bone age assessment attention eraser quantitative feature metacarpal bones
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Microscopic analysis of mechanical anisotropy and damage evolution of 3D printed rock-like samples under uniaxial compressive tests 被引量:1
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作者 Yulong Shao Jingwei Yang +3 位作者 Jineon Kim Jae-Joon Song Juhyuk Moon Jianyong Han 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期688-704,共17页
Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects ... Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects such as cracks and pores.In this study,3DP gypsum samples with different printing directions were subjected to a series of uniaxial compression tests with in situ micro-computed tomography(micro-CT)scanning to quantitatively investigate their mechanical anisotropic properties and damage evolution characteristics.Based on the two-dimensional(2D)CT images obtained at different scanning steps,a novel void ratio variable was derived using the mean value and variance of CT intensity.Additionally,a constitutive model was formulated incorporating the proposed damage variable,utilizing the void ratio variable.The crack evolution and crack morphology of 3DP gypsum samples were obtained and analyzed using the 3D models reconstructed from the CT images.The results indicate that 3DP gypsum samples exhibit mechanical anisotropic characteristics similar to those found in naturally sedimentary rocks.The mechanical anisotropy is attributed to the bedding planes formed between adjacent layers and pillar-like structures along the printing direction formed by CaSO_(4)·2H_(2)O crystals of needle-like morphology.The mean gray intensity of the voids has a positive linear relationship with the threshold value,while the CT variance and void ratio have concave and convex relationships,respectively.The constitutive model can effectively match the stress–strain curves obtained from uniaxial compression experiments.This study provides comprehensive explanations of the failure modes and anisotropic mechanisms of 3DP gypsum samples,which is important for characterizing and understanding the failure mechanism and microstructural evolution of 3DP rocks when modeling natural rock behavior. 展开更多
关键词 Quantitative analysis Three-dimensional printing(3DP) Gypsum samples In situ micro-computed tomography(micro-CT)scanning Mechanical anisotropy Bedding planes Damage evolution
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