期刊文献+
共找到19,604篇文章
< 1 2 250 >
每页显示 20 50 100
Aqueous Ionic Liquid Mediated Hydrolysis of Native Corn Starch to Obtain Different Low Molecular Weight Starch
1
作者 YANG Rui WANG Xiaolin +1 位作者 DANG Qian LIU Zhengping 《高等学校化学学报》 北大核心 2026年第1期153-161,共9页
In this work,we proposed a strategy for the hydrolysis of native corn starch after the treatment of corn starch in an ionic liquid aqueous solution,and it is an awfully“green”and simple means to obtain starch with l... In this work,we proposed a strategy for the hydrolysis of native corn starch after the treatment of corn starch in an ionic liquid aqueous solution,and it is an awfully“green”and simple means to obtain starch with low molecular weight and amorphous state.X-ray diffraction results revealed that the natural starch crystalline region was largely disrupted by ionic liquid owing to the broken intermolecular and intramolecular hydrogen bonds.After hydrolysis,the morphology of starch changed from particles of native corn starch into little pieces,and their molecular weight could be effectively regulated during the hydrolysis process,and also the hydrolyzed starch samples exhibited decreased thermal stability with the extension of hydrolysis time.This work would counsel as a powerful tool for the development of native starch in realistic applications. 展开更多
关键词 Native corn starch Ionic liquid HYDROLYSIS Molecular weight
在线阅读 下载PDF
Effects of Different Moisture Content on the Quality Characteristics of Sichuan Sausage during Frozen Storage
2
作者 Qi ZHOU Jiamin ZHANG +2 位作者 Lili JI Wei WANG Ting BAI 《Agricultural Biotechnology》 2026年第1期26-35,共10页
Sichuan sausages with moisture contents of 40%,45%,50%,and 60% were stored at-18℃for durations of 0,2,4,6,and 8 weeks to evaluate the effect of moisture content on the quality attributes of Sichuan sausages during fr... Sichuan sausages with moisture contents of 40%,45%,50%,and 60% were stored at-18℃for durations of 0,2,4,6,and 8 weeks to evaluate the effect of moisture content on the quality attributes of Sichuan sausages during frozen storage.Product indicators including pH,colour,thiobarbituric acid reactive substances(TBARS),total volatile basic nitrogen(TVB-N),texture,electronic nose(E-nose)response,and water-holding capacity(thawing and cooking losses)were determined.The results indicated that as storage time increased,water retention in Sichuan sausages with different moisture contents decreased,while the degree of protein and lipid oxidation increased.This led to an increase in pH value,a colour shift from red-bright to grey-brown,and a deterioration in palatability.Among the samples,sausages with 50% moisture content exhibited the lowest thawing and cooking losses,indicating superior water-holding capacity.After 8 weeks of storage,TBARS and TVB-N values for the 50% moisture group were 19.5%and 2.5%lower,respectively,than those of the 40%and 45%moisture groups,indicating a reduced degree of oxidation.Furthermore,Sichuan sausage with 50%moisture content demonstrated an appropriate pH and colour difference,along with excellent texture and flavour,as evidenced by its higher toughness and satisfactory hardness.In conclusion,Sichuan sausage with 50% moisture content demonstrated the highest overall quality under frozen storage conditions. 展开更多
关键词 Sichuan sausage Moisture content Storage time Quality characteristics
在线阅读 下载PDF
TSMixerE:Entity Context-Aware Method for Static Knowledge Graph Completion
3
作者 Jianzhong Chen Yunsheng Xu +2 位作者 Zirui Guo Tianmin Liu Ying Pan 《Computers, Materials & Continua》 2026年第4期2207-2230,共24页
The rapid development of information technology and accelerated digitalization have led to an explosive growth of data across various fields.As a key technology for knowledge representation and sharing,knowledge graph... The rapid development of information technology and accelerated digitalization have led to an explosive growth of data across various fields.As a key technology for knowledge representation and sharing,knowledge graphs play a crucial role by constructing structured networks of relationships among entities.However,data sparsity and numerous unexplored implicit relations result in the widespread incompleteness of knowledge graphs.In static knowledge graph completion,most existing methods rely on linear operations or simple interaction mechanisms for triple encoding,making it difficult to fully capture the deep semantic associations between entities and relations.Moreover,many methods focus only on the local information of individual triples,ignoring the rich semantic dependencies embedded in the neighboring nodes of entities within the graph structure,which leads to incomplete embedding representations.To address these challenges,we propose Two-Stage Mixer Embedding(TSMixerE),a static knowledge graph completion method based on entity context.In the unit semantic extraction stage,TSMixerE leveragesmulti-scale circular convolution to capture local features atmultiple granularities,enhancing the flexibility and robustness of feature interactions.A channel attention mechanism amplifies key channel responses to suppress noise and irrelevant information,thereby improving the discriminative power and semantic depth of feature representations.For contextual information fusion,a multi-layer self-attentionmechanism enables deep interactions among contextual cues,effectively integrating local details with global context.Simultaneously,type embeddings clarify the semantic identities and roles of each component,enhancing the model’s sensitivity and fusion capabilities for diverse information sources.Furthermore,TSMixerE constructs contextual unit sequences for entities,fully exploring neighborhood information within the graph structure to model complex semantic dependencies,thus improving the completeness and generalization of embedding representations. 展开更多
关键词 Knowledge graph knowledge graph complementation convolutional neural network feature interaction context
在线阅读 下载PDF
壶中天地 宜兴陶书局
4
作者 方晓彬 戴若玙 《室内设计与装修》 2026年第2期26-31,共6页
陶书局坐落在宜兴陶二厂文化街区。在这个街区上,业主希望创造2个地标,一个是隈研吾设计的U CCA陶艺术馆,另一个就是引进了朵云书院,并希望创造一个跟陶瓷有关的书店,于是有了现在的陶书局。在设计之初的沟通中,老紫砂艺人的一句话“制... 陶书局坐落在宜兴陶二厂文化街区。在这个街区上,业主希望创造2个地标,一个是隈研吾设计的U CCA陶艺术馆,另一个就是引进了朵云书院,并希望创造一个跟陶瓷有关的书店,于是有了现在的陶书局。在设计之初的沟通中,老紫砂艺人的一句话“制壶如做人”触动了设计团队,于是团队便以此作为项目的设计主题。围绕这个主题建立起叙事的框架,即制壶的3个阶段:第一炼泥与制坯,第二窑烧,第三成器。分别对应空间的3个区域:泥土,洞穴,仙境;也象征做人要历经的3种状态:磨炼,考验,还有升华。 展开更多
关键词 朵云书院 制壶如做人 炼泥与制坯
在线阅读 下载PDF
Functional outcome and patient satisfaction 5y after laser vision correction
5
作者 Ran Gao Yu Han +4 位作者 Jie Qin Yu-Shan Xu Yu Li Xiao-Tong Lyu Feng-Ju Zhang 《International Journal of Ophthalmology(English edition)》 2026年第1期123-131,共9页
AIM:To investigate the association between functionaloutcomes and postoperative patient satisfaction 5y aftersmall incision lenticule extraction(SMILE)and femtosecondlaser-assisted in situ keratomileusis(FS-LASIK).MET... AIM:To investigate the association between functionaloutcomes and postoperative patient satisfaction 5y aftersmall incision lenticule extraction(SMILE)and femtosecondlaser-assisted in situ keratomileusis(FS-LASIK).METHODS:This is a cross-sectional study.Thepatients underwent basic ophthalmic examinations,axiallength measurement,wide-field fundus photography,andaccommodation function testing.Behavioral habits datawere collected using a self-administered questionnaire,andvisual symptoms were assessed with the Quality of Vision(QoV)questionnaire.Postoperative satisfaction was alsorecorded.RESULTS:Totally 410 subjects[820 eyes,160males(39.02%)and 250 females(60.98%)]who hadundergone SMILE or FS-LASIK 5y ago were enrolled.Themean(standard deviation,SD)age of all patients was29.83y(6.69).The mean(SD)preoperative manifest SEwas-5.80(2.04)diopters(D;range:-0.88 to-13.75).Patient satisfaction at 5y after undergoing SMILE or FSLASIKwas 91.70%.Patients were categorized into twogroups:dissatisfied group and satisfied group.Significantdifferences were observed between the two groups in termsof age(P=0.012),sex(P=0.021),preoperative degreeof myopia(P=0.049),postoperative visual symptoms(frequency,P=0.043;severity,P<0.001;bothersome,P=0.018),difficulty driving at night(P=0.001),andaccommodative amplitude(AMP,P=0.020).Multivariateanalysis confirmed that female sex(P=0.024),severityof visual symptoms(P=0.009),and difficulty driving atnight(P=0.006)were significantly associated with lowersatisfaction.The dissatisfied group showed higher rates ofstarbursts,double or multiple images,and high myopia,but lower age.The frequency,severity,and bothersome ofdistortion exhibited decreased with increasing age.CONCLUSION:Patient satisfaction 5y after SMILEand FS-LASIK is high and stable.Difficulty driving at night,sex,and severity of visual symptoms are important factorsinfluencing patient satisfaction.Special attention should bepaid to younger highly myopic female patients,particularlythose with starbursts and double or multiple images.It is crucial to monitor postoperative visual outcomesand provide patients with comprehensive preoperativecounseling to enhance long-term satisfaction. 展开更多
关键词 patient satisfaction MYOPIA VISION small incision lenticule extraction femtosecond laser-assisted in situ keratomileusis
原文传递
Ultra-fast and high-responsivity self-powered vis-NIR photodetector via surface charge transfer doping in MoTe_(2)/ReS_(2)heterostructures
6
作者 Haozhe Ruan Yongkang Liu +5 位作者 Jianyu Wang Linjiang Xie Yixuan Wang Mengting Dong Zhangting Wu Liang Zheng 《Journal of Semiconductors》 2026年第1期99-106,共8页
The development of optoelectronic technologies demands photodetectors with miniaturization,broadband operation,high sensitivity,and low power consumption.Although 2D van der Waals(vd W)heterostructures are promising c... The development of optoelectronic technologies demands photodetectors with miniaturization,broadband operation,high sensitivity,and low power consumption.Although 2D van der Waals(vd W)heterostructures are promising candidates due to their built-in electric fields,ultrafast photocarrier separation,and tunable bandgaps,defect states limit their performance.Therefore,the modulation of the optoelectronic properties in such heterostructures is imperative.Surface charge transfer doping(SCTD)has emerged as a promising strategy for non-destructive modulation of electronic and optoelectronic characteristics in two-dimensional materials.In this work,we demonstrate the construction of high-performance p-i-n vertical heterojunction photodetectors through SCTD of MoTe_(2)/ReS_(2)heterostructure using p-type F_(4)-TCNQ.Systematic characterization reveals that the interfacial doping process effectively amplifies the built-in electric field,enhancing photogenerated carrier separation efficiency.Compared to the pristine heterojunction device,the doped photodetector exhibits remarkable visible to nearinfrared(635-1064 nm)performance.Particularly under 1064 nm illumination at zero bias,the device achieves a responsivity of 2.86 A/W and specific detectivity of 1.41×10^(12)Jones.Notably,the external quantum efficiency reaches an exceptional value of 334%compared to the initial 11.5%,while maintaining ultrafast response characteristics with rise/fall times of 11.6/15.6μs.This work provides new insights into interface engineering through molecular doping for developing high-performance vd W optoelectronic devices. 展开更多
关键词 MoTe_(2)/ReS_(2)heterostructure broadband photodetector surface charge transfer doping P-I-N
在线阅读 下载PDF
Recyclable,reprocessable,and biodegradable cellulosic bioplastics enabled by a reactive eutectic network
7
作者 Huanhuan Wu Ren’ai Li 《Science China Materials》 2026年第3期1665-1676,共12页
Growing demand for sustainable,high-performance materials is driving research to replace petroleumbased plastics with abundant biomass,especially cellulose.However,the effective modification and functionalization of c... Growing demand for sustainable,high-performance materials is driving research to replace petroleumbased plastics with abundant biomass,especially cellulose.However,the effective modification and functionalization of cellulose is often impeded by complex processing requirements and limited performance tunability.Here,an innovative“active”green medium strategy based on an ethyl cellulose/thymol eutectic system is reported,enabling in situ chemical modification of eutectic components and the construction of dynamic self-adaptive networks without external catalysts or initiators.Through precise molecular design,dynamic boroxine networks and acrylate crosslinking networks are synergistically integrated into the cellulosic bioplastic(CBP)matrix.The resulting CBP-A2B8 exhibits exceptional optical transparency(~85%),superior mechanical properties(tensile strength~30 MPa),facile thermal processability,and closed-loop recyclability.Its chemical structure and mechanical performance remain highly stable even after 20 hot-compression recycling cycles.Complete biodegradation occurs under natural environmental conditions within approximately 100 days.Furthermore,the bioplastic,when combined with silver nanowires,forms high-performance flexible transparent conductive films successfully applied in customizable electroluminescent devices.Post-lifecycle,device components(silver nanowires and CBP matrix)are efficiently separated and recycled using a straightforward solvent-based method.This eutectic system-mediated strategy offers a novel pathway for the development of sustainable,high-performance bioplastics with a closed-loop lifecycle. 展开更多
关键词 cellulosic bioplastics eutectic system self-adaptive networks biodegradation RECYCLABILITY
原文传递
Comparative studies on nanocarbon-modified carbon paper electrodes for enhanced electrocatalytic performance in vanadium redox flow batteries
8
作者 Jaeho Jo Jaeeon Chang Doohwan Lee 《新型炭材料(中英文)》 北大核心 2026年第1期196-208,共13页
Vanadium redox flow batteries(VRFBs)are a means of large-scale energy storage due to their excellent scalability,safety,long cycling life,and decoupled power and energy capacities.However,the slow redox kinetics of va... Vanadium redox flow batteries(VRFBs)are a means of large-scale energy storage due to their excellent scalability,safety,long cycling life,and decoupled power and energy capacities.However,the slow redox kinetics of vanadium species on conventional carbon electrodes remains a major limitation to their performance.We investigated the deposition of carbon black,carbon nanotubes,and electrochemically exfoliated graphene(Exf-Gr)onto thermally-activated carbon paper(ACP)by spray coating to increase the electrode electrocatalytic activity.The modified electrodes were characterized using scanning electron microscopy,X-ray diffraction,Raman spectroscopy,X-ray photoelectron microscopy,and surface area analysis,while their electrochemical properties were evaluated by cyclic voltammetry,electrochemical impedance spectroscopy,and singlecell VRFB testing.Among the modified electrodes,Exf-Gr/ACP had the best performance,achieving a 2.9-fold reduction in charge transfer resistance compared to pristine ACP and delivering 2.5 times the discharge capacity in single-cell tests.This improvement is attributed to Exf-Gr’s high surface area,favorable catalytic activity,and excellent dispersion on the ACP substrate.Surface modification with electrochemically exfoliated graphene is a highly effective strategy for improving the electrode performance in VRFB systems,with significant implications for large-scale energy storage. 展开更多
关键词 Vanadium redox flow battery Carbon paper electrode Exfoliated graphene Carbon nanotube ELECTROCATALYSIS
在线阅读 下载PDF
On AlN_(P)/Mg-Zn-Cu cast composites with low expansion and high thermal conductivity
9
作者 Shu-sen Wu Lu Chen +2 位作者 Shu-lin Lü Wei Guo Jian-yu Li 《China Foundry》 2026年第1期101-107,共7页
There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with h... There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with high thermal conductivity.Furthermore,it explores the preparation of AlN_(P)/Mg-Zn-Cu composites featuring low coefficients of thermal expansion.The stir casting method was utilized to fabricate the composites and an investigation was conducted to examine their microstructure and thermal properties.Results indicate that the addition of AlN_(P)reduces the thermal expansion coefficient while maintaining relatively high thermal conductivity.Specifically,the AlN_(P)/Mg-0.5Zn-0.5Cu composite with 30wt.%AlN_(P)achieves a thermal conductivity of 132.7 W·m^(-1)·K^(-1)and a thermal expansion coefficient of 18.5×10^(-6)K^(-1),rendering it suitable for electronic packaging applications where thermal management is critical. 展开更多
关键词 thermal expansion thermal conductivity magnesium-matrix composites Mg-Zn-Cu alloy
在线阅读 下载PDF
Effects and mechanisms of adipose tissue-derived extracellular vesicles in vascular inflammation and dysfunction
10
作者 Daphne Lintsen Bieke Broux 《Neural Regeneration Research》 2026年第5期2005-2006,共2页
Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated ... Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated to neuroinflammation,such as Alzheimer's disease,it is now shown to precede pathological protein aggregations. 展开更多
关键词 pathological protein aggregations vascular inflammation NEUROINFLAMMATION neurodegenerative diseasessuch multiple sclerosis Alzheimers disease adipose tissue derived extracellular vesicles alzheimers diseaseit
暂未订购
Spinal cord injury–associated disruption of the autonomic immune control:Does biological sex matter?
11
作者 Sara Rito-Fernandes António J.Salgado +1 位作者 Nuno A.Silva Susana Monteiro 《Neural Regeneration Research》 2026年第1期298-299,共2页
The impact of spinal cord injury(SCI)on the immune system is increasingly recognized in a field traditionally focused on motor impairments.SCI can seriously affect the immune system by progressively disrupting the reg... The impact of spinal cord injury(SCI)on the immune system is increasingly recognized in a field traditionally focused on motor impairments.SCI can seriously affect the immune system by progressively disrupting the regulatory mechanisms that control immune responses.This dysregulation varies widely among patients and can evolve over time,ranging from systemic inflammatory responses to immunosuppression,greatly contributing to the morbidity and mortality of individuals with SCI(Bao et al.,2011;Brennan et al.,2024). 展开更多
关键词 MORTALITY SPINAL
暂未订购
A Self-healing and Flame-retardant Poly(urethane-urea)Elastomer Driven by Hydrogen Bonds and Phosphorus-Nitrogen Synergy
12
作者 Chen-Qing Wu Zeng Wang +2 位作者 Tian-Yu Xiu Xu Zhu Jun-Min Wan 《Chinese Journal of Polymer Science》 2026年第2期499-512,I0015,共15页
Although poly(urethane-urea)elastomers(PUEs)possess excellent mechanical properties and durability,their inherent flammability and inability to self-repair after damage significantly limits their applications in high-... Although poly(urethane-urea)elastomers(PUEs)possess excellent mechanical properties and durability,their inherent flammability and inability to self-repair after damage significantly limits their applications in high-end fields.To address this challenge,this study employs a supramolecular chemistry approach by simultaneously incorporating multiple hydrogen bonds as dynamic cross-linking points and a phosphorus-nitrogen synergistic flame-retardant structure into the poly(urethane-urea)network.The multiple hydrogen bonds endow the material with efficient intrinsic self-healing capability,while the phosphorus-nitrogen flame retardant ensures outstanding thermal stability and flame resistance,leading to the successful synthesis of a high-performance multifunctional poly(urethane-urea)elastomer.Experimental results demonstrated that when the content of the flame retardant diethyl(2-((2-aminoethyl)amino)ethyl)phosphoramidate(DEPTA)was 10 wt%,the resulting PUE/10%DEPTA achieved a V-0 rating in the vertical burning test,with a limiting oxygen index(LOI)of 30%.Concurrently,the elastomer maintained good toughness,exhibiting a tensile strength of 27.3 MPa,an elongation at break of 601%,and a self-healing efficiency of up to 94.46%.This breakthrough shows significant promise for advanced engineering applications that demand fire safety,structural durability,and extended service life through self-repair. 展开更多
关键词 Poly(urethane-urea)elastomer Phosphorus-nitrogen flame retardant Mechanical properties Self-healing capability
原文传递
A Spiderweb-inspired Electrostatic-microstructure Hybrid Adhesive Flexible Net for Space Debris Capture
13
作者 Ruilin Li Peng Qiao +4 位作者 Lifu Liu Zean Yuan Shuhong Huang Huijiang Wang Rui Chen 《Journal of Bionic Engineering》 2026年第1期257-273,共17页
The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely sole... The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely solely on a passive wrap-ping mechanism,limit their capacity to capture objects within a specific size range and make it challenging to handle unexpected situations.Inspired by spider webs,which combine wrapping and adhering to capture prey of various sizes,we present a new type of net(envelope diameter:208.49 mm)for on-orbit capture.This net adopts a spiral symmetric structure similar to spider webs,incorporates electrostatic-microstructure hybrid adhesives,and increases the maximum contact area by 38.31%,allowing it to capture debris ranging from fragments smaller than the mesh size(envelope diam-eter:2.7 mm-4.4 mm)to larger objects(envelope diameter:270 mm),and effectively grasps flexible items(450 mm2),planar items(350 mm2)and three-dimensional items(160 mm3).Moreover,to validate the net's capability for wrapping and adhesion,simulations and experiments are demonstrated that this dual capture method can effectively handle various targets. 展开更多
关键词 Hybrid adhesives Electrostatic adhesion Net capturing Bio-inspiration
在线阅读 下载PDF
Solid-Polymer-Electrolyte Interphase Inductively Formed by Surface Chemistry to Stabilize the High Ni Cathode in Sulfide-Based All-Solid-State Lithium Batteries
14
作者 Guo Tang Gengzhong Lin +5 位作者 Yicheng Deng Hui Li Yuliang Cao Yongjin Fang Hanxi Yang Xinping Ai 《Carbon Energy》 2026年第1期26-37,共12页
High-nickel cathode,LiNi0.8Co0.1Mn0.1O_(2)(NCM811),and sulfide-solid electrolyte are a promising combination for all-solid-state lithium batteries(ASSLBs).However,this combination faces the issue of interfacial instab... High-nickel cathode,LiNi0.8Co0.1Mn0.1O_(2)(NCM811),and sulfide-solid electrolyte are a promising combination for all-solid-state lithium batteries(ASSLBs).However,this combination faces the issue of interfacial instability between the cathode and electrolyte.Given the surface alkalinity of NCM811,we propose a strategy to construct a solid-polymer-electrolyte(SPE)interphase on NCM811 surface by leveraging the surface alkaline residues to nucleophilically initiate the in-situ ring-opening polymerization of cyclic organic molecules.As a proof-of-concept,this study demonstrates that the ring-opening copolymerization of 1,3-dioxolane and maleic anhydride produces a homogeneous,compact,and conformal SPE layer on NCM811 surface to prevent the cathode from contact and reaction with Li6PS5Cl solid-state electrolyte.Consequently,the SPE-modified-NCM811 in ASSLBs exhibits high capacities of 193.5 mA h g^(-1) at 0.2 C,160.9 mA h g^(-1) at 2.0 C and 112.3 mA h g^(-1) at 10 C,and particularly,excellent long-term cycling stabilities over 11000 cycles with a 71.95%capacity retention at 10 C at 25℃,as well as a remained capacity of 117.9 mA h g^(-1) after 8000 cycles at 30 C at 60℃,showing a great application prospect.This study provides a new route for creating electrochemically and structurally stable solid-solid interfaces for ASSLBs. 展开更多
关键词 all-solid-state lithium batteries Ni-rich layered oxides nucleophilic reaction solid-polymer-electrolyte interphase sulfide solid electroly
在线阅读 下载PDF
Revision of the absolute configurations of Pallavicinia diterpenoids and further discovery of their Diels-Alder cycloadducts
15
作者 Jiao-Zhen Zhang Cheng-Min Zhang +7 位作者 Yong-Jie Wang Pei-Lin Wu Rui-Feng Liu Ye Li Ming-Zhu Zhu Shuang-Zhi Yuan Ze-Jun Xu Hong-Xiang Lou 《Chinese Chemical Letters》 2026年第1期394-398,共5页
Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is c... Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is crucial for the confirmation of absolute configurations.Ignoring critical parameters will lead to false structure,which may confuse the total synthesis and drug development.Herein,the configurations of seven heterogeneous Pallavicinia diterpenoids(PDs) isolated from Pallavicinia liverworts are revised using a combination of single-crystal X-ray diffraction and electronic circular dichroism(ECD) calculations.Meanwhile,identification of five unprecedented PD heterodimers PD-dimers A-E(18-22) along with eleven previously undescribed PDs(5-9,13-17,23) obtained by the reinvestigation of the Chinese liverwort Pallavicinia subciliata have resulted in corrections and support the revised conclusions. 展开更多
关键词 REVISION Absolute configurations Pallavicinia diterpenoids LIVERWORT Single-crystal X-ray diffraction Electronic circular dichroism calculations
原文传递
Hypervelocity impact response and protection for the track steels of rocket sled system via light-gas gun experiments
16
作者 Siwei Zhao Yi Zeng +5 位作者 Xuewen Zhou Weixing Zhao Botao Xie Jianbin Jing Yan Chen Yilun Liu 《Defence Technology(防务技术)》 2026年第2期282-293,共12页
Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this stud... Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms. 展开更多
关键词 Hypervelocity rocket sled Gouge of the track steels Two-stage light-gas gun Microstructural characterization Coating protection
在线阅读 下载PDF
Amorphous phase engineering in Ni-doped MoS_(2)@C:synergistic structural-electronic modulation for high-energy-power sodium-ion hybrid capacitors
17
作者 Ziyang Jia Yishuang He +9 位作者 Xiaotong Zhang Xi Chen Xinhai Yuan Lili Liu Lijun Fu Yuhui Chen Tao Wang Xinbing Cheng Faxing Wang Yuping Wu 《Science China Chemistry》 2026年第2期768-776,共9页
Sodium-ion hybrid capacitors(SICs)offer inherent energy-power synergy but are constrained by mismatched kinetics and life spans between the anode and cathode materials.Two-dimensional MoS_(2)@C composites demonstrate ... Sodium-ion hybrid capacitors(SICs)offer inherent energy-power synergy but are constrained by mismatched kinetics and life spans between the anode and cathode materials.Two-dimensional MoS_(2)@C composites demonstrate excellent kinetics and structural stability,thanks to the built-in electric field of the carbon heterostructure and its adaptability to volume changes.Yet,the carbon shell imposes a physical barrier to interfacial Na^(+)diffusion,while deep discharge induces the formation of crystalline Na_(2)S,accompanied by severe volumetric expansion and sluggish reversibility—factors that accelerate capacity fading and structural degradation.To address these challenges,a trace-level Ni doping strategy is introduced,enabling precise modulation of the composite's interlayer structure,electronic configuration,and reaction pathway.Ni incorporation expands the MoS_(2) interlayer spacing,reconstructs short-range ordered nanocrystals within a hierarchically porous network,and promotes Na^(+)diffusion by weakening interlayer van der Waals forces.Orbital hybridization between Ni-3d and Mo-4d/S-3p states enhances electronic conductivity and reduces charge transfer resistance.Critically,Ni doping enhances electron transfer from Ni to sulfur,which weakens Na–S bonds and promotes the formation of amorphous Na_(2)S,thereby suppressing crystalline Na_(2)S and enabling a reversible MoS_(2)/Na_(2)S conversion mechanism for improved structural stability and cycling performance.As a result,the optimized MoS_(2)-Ni@C anode delivers a high reversible capacity of 334 mAh g^(-1)at 10 A g^(-1)with 68%retention after 10,000 cycles.When assembled into a SIC device(MoS_(2)-Ni@C//AC),it achieves an energy density of 135 Wh kg^(-1)at a power density of 60.8 kW kg^(-1)(based on anode mass),with 76%retention over 3,000 cycles. 展开更多
关键词 hybrid capacitor sodium ion ANODE MoS_(2) amorphous phase engineering
原文传递
Detection of vitreoretinal interface abnormalities from OCT images based on DS-YOLOv7 network
18
作者 Xin Zhou Ying Fan +6 位作者 Gaowei Li Menghan Li Weifang Zhu Dehui Xiang Xinjian Chen Xun Xu Fei Shi 《Journal of Innovative Optical Health Sciences》 2026年第2期102-115,共14页
Advances in optical coherence tomography(OCT)technology allow a clear view of the vitreoretinal interface(VRI).The abnormality of the VRI is one of the common symptoms of high myopia,mainly including posterior vitreou... Advances in optical coherence tomography(OCT)technology allow a clear view of the vitreoretinal interface(VRI).The abnormality of the VRI is one of the common symptoms of high myopia,mainly including posterior vitreous detachment(PVD)and epiretinal membrane(ERM).They can cause severe damage to the structure and function of the retina,leading to permanent vision loss.Therefore,fully automated detection of abnormalities at the VRI is crucial for the management of high myopia.This paper presents a DS-YOLOv7 network aimed at accurately identifying abnormalities,including partial PVD,complete PVD,and ERM from retinal OCT images.Built upon the YOLOv7 network,the proposed model integrates the advanced dynamic snake convolution(DSConv)module to capture the curvilinear characteristics of lesions,and the mixture of attention and convolution(ACMix)module to improve the precision and robustness of feature extraction through effective fusion of self-attention mechanisms and convolution.Moreover,the introduction of the efficient complete intersection-over-union(ECIoU)loss function further enhances the coordinate regression capability of the model.Threefold cross-validation on a dataset with 1973 OCT B-scans from 46 patients shows that the DS-YOLOv7 achieved superior performance in vitreoretinal interface abnormality detection,with mAP@0.5 of 0.714,mAP@0.75 of 0.438,and mAP@0.5:0.95 of 0.424.The proposed model can provide an accurate and efficient diagnostic tool for patients with high myopia. 展开更多
关键词 YOLOv7 dynamic snake convolution mixture of attention and convolution optical coherence tomography vitreoretinal interface abnormality
原文传递
Succinic acid-driven gut-fat axis orchestrates abdominal fat deposition in chickens via adipocyte-macrophage crosstalk
19
作者 Jiahui Chen Chuang Hu +6 位作者 Yu Wang Lin Qi Haoqi Peng Genghua Chen Qinghua Nie Xiquan Zhang Wen Luo 《Journal of Animal Science and Biotechnology》 2026年第1期356-375,共20页
Background Excessive abdominal fat in broilers not only reduces feed efficiency and increases processing costs but also raises environmental concerns.This pathological overaccumulation results from complex metabolic d... Background Excessive abdominal fat in broilers not only reduces feed efficiency and increases processing costs but also raises environmental concerns.This pathological overaccumulation results from complex metabolic dysregulation across multiple organs.While current research largely centers on adipogenesis within adipose tissue,a comprehensive understanding of the cross-organ regulatory factors influencing this process remains elusive.Results Here,we employed a high-fat diet(HFD)model and multi-omics approaches to investigate cross-organ regulatory mechanisms underlying abdominal fat deposition in broilers.Our results demonstrated that HFD not only promoted fat accumulation but also altered meat quality traits.Through 16S rRNA amplicon sequencing,we identified significant gut microbiota dysbiosis in HFD-fed chickens,manifested by an increased abundance of Lactobacillus and a decreased abundance of Enterococcus.However,jejunal microbiota transplantation from HFD donors did not induce abdominal fat deposition in recipient chickens.Metabolomic profiling revealed that HFD elevated the level of succinic acid,a metabolite positively correlated with Lactobacillus abundance and potentially generated by Lactobacillus.This increase in succinic acid(SA)further triggered metabolic inflammation response in both jejunal tissue and serum.In vivo validation established succinic acid as a key inflammatory mediator facilitating HFD-induced cross-organ communication between the jejunum and abdominal adipose tissue,enhancing intestinal lipid uptake and subsequent abdominal fat deposition.Bulk and single-nucleus RNA sequencing(snRNA-seq)revealed that HFD induced macrophage population expansion and intensified adipocyte-macrophage crosstalk.Adipocyte-macrophage co-culture systems further elucidated that macrophages are an indispensable factor in succinic acid-induced fat deposition.Conclusion This study delineates a succinic acid-driven"gut-fat axis"governing abdominal fat deposition in broilers,integrating gut microbiota dysbiosis and macrophage-mediated inflammatory adipogenesis.By identifying succinic acid as a cross-organ signaling molecule that enhances lipid absorption and activates macrophage-dependent adipogenesis,we establish systemic metabolic-immune crosstalk as a pivotal regulatory mechanism.These findings redefine fat deposition as a process extending beyond adipose-centric models,advancing multi-omics-guided strategies for sustainable poultry production. 展开更多
关键词 Abdominal fat deposition Gut-fat axis High fat diet Single nuclear sequencing Succinic acid
在线阅读 下载PDF
Photoreforming polylactic acid plastics into pyruvate over CdS/Bi_(4)Ti_(3)O_(12)S-scheme heterojunction:Successive removal of hydrogen fromα-C
20
作者 Xinxin Liang Yongqian Cui +6 位作者 Qingyun Tian Tingting Jia Qibing Dong Ximing Li Ting Gao Chao Ma Chuanyi Wang 《Chinese Chemical Letters》 2026年第2期629-634,共6页
Photoreforming poly(lactic acid)(PLA)plastics into pyruvic acid(PA)coupled with hydrogen evolution is of great significance for sustainable development.However,a significant challenge lies inα-OH bond cleaving of lac... Photoreforming poly(lactic acid)(PLA)plastics into pyruvic acid(PA)coupled with hydrogen evolution is of great significance for sustainable development.However,a significant challenge lies inα-OH bond cleaving of lactic acid(LA).Herein,CdS/Bi_(4)Ti_(3)O_(12)composite is fabricated,bridged by Bi−S bonds,through in-situ growth of CdS nanoparticles on Bi_(4)Ti_(3)O_(12)nanoflowers for the successive removal of hydrogen fromα-C in LA.In-situ X-ray photoelectron spectroscopy confirms the S-scheme carriers transfer route and interfacial Bi−S bond in CdS/Bi_(4)Ti_(3)O_(12).Consequently,the photo-electrons and holes with extended lifetimes and strong redox potential accumulate in the CdS conduction band and Bi_(4)Ti_(3)O_(12)valence band,respectively,as evidenced by in-situ electron spin resonance and time-resolved photoluminescence.This facilitates the generation of·OH radicals,which further participate in the successive dehydrogenation reaction of LA.Consequently,the photoreforming efficiencies of converting PLA into PA and H_(2)by CdS/Bi_(4)Ti_(3)O_(12)are 1.7 and 3.16 mmol g^(-1)h^(-1),which are respectively 2.8 and 22 times higher than that by pristine Bi_(4)Ti_(3)O_(12).The present work provides a new approach for designing S-scheme to achieve hydrogen production and value-added conversion of plastics. 展开更多
关键词 H_(2)evolution S-scheme Photoreforming plastic Valuable chemical Plastic oxidation
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部