期刊文献+
共找到4,771篇文章
< 1 2 239 >
每页显示 20 50 100
Three-dimensional supramolecular polymer frameworks with precisely tunable and large apertures for enzyme encapsulation
1
作者 Runtan Gao Yang Zong +2 位作者 Tingting Li Na Liu Zongquan Wu 《Chinese Chemical Letters》 2026年第1期361-367,共7页
Three-dimensional supramolecular organic frameworks with precisely tunable pore sizes are highly demanded for a wide range of applications,e.g.,encapsulating enzymes to enhance their stability,activity,and reusability... Three-dimensional supramolecular organic frameworks with precisely tunable pore sizes are highly demanded for a wide range of applications,e.g.,encapsulating enzymes to enhance their stability,activity,and reusability.However,precise control and tune the pore size of such frameworks still remains a significant challenge to date.In this study,we constructed supramolecular polymer frameworks using rigid tetrahedral star polyisocyanides with tunable length and sufficiently narrow distribution as building block.First,a series of tetrahedral four-arm star polyisocyanides with controlled chain lengths and narrow molecular weight distributions was prepared via the Pd(Ⅱ)-catalyzed living isocyanide polymerization.Then 2-ureido-4[1H]-pyrimidinone(Upy) unit was installed onto each chain-end of polyisocyanide arms via post-polymerization functionalization.Leveraging the supramolecular hydrogen bonding interactions between the terminal Upy units,well-ordered supramolecular polymer frameworks were readily obtained.Notably,the pore size was dependent on the chain length of the polyisocyanide arms.Precisely control the chain length of polyisocyanide arms,supramolecular polymer frameworks with pore sizes ranging from 5.06 nm to 9.72 nm were achieved.These frameworks,with tunable and large pore apertures,demonstrated exceptional capabilities in encapsulating enzymes of different sizes,such as lipase(TL),horseradish peroxidase(HRP),and glucose oxidase(GOx).The encapsulated enzymes exhibited significantly enhanced catalytic activity and durability.Moreover,the frameworks' tunable and large pore apertures facilitated the co-encapsulation of multiple enzymes,enabling efficient dual-enzyme cascade reactions. 展开更多
关键词 Supramolecular organic frameworks Living polymerization Supramolecular self-assembly Polyisocyanide Enzyme encapsulation
原文传递
Multilevel encapsulation-engineered ultra-stable flexible scintillator films for high-resolution X-ray imaging
2
作者 Mengke Bai Rui Zhang +13 位作者 Jiahuan Guo Fei Zhang Yurun Liang Mengke Li Yingyu Zhou Xue Yan Yubo Wang Liyuan Wu Yuhang Hou Gaoyu Chen Yatao Zou Wenqing Liang Gaofeng Zhao Weidong Xu 《Science China Materials》 2026年第3期1440-1447,共8页
Lead halide perovskites have emerged as promising scintillators for X-ray imaging owing to their high Xray absorption efficiency,excellent luminescence properties,and facile synthesis.However,their intrinsic ionic nat... Lead halide perovskites have emerged as promising scintillators for X-ray imaging owing to their high Xray absorption efficiency,excellent luminescence properties,and facile synthesis.However,their intrinsic ionic nature poses a fundamental challenge in simultaneously achieving high photoluminescence efficiency and environmental robustness.Here,we introduce a multilevel encapsulation strategy by sequentially coating CsPbBr_(3)quantum dots(QDs)with Cs_(4)PbBr_(6),SiO_(2),and polydimethylsiloxane(PDMS),thereby synergistically enhancing both optical performance and stability.Cs_(4)PbBr_(6)effectively passivates surface defects of CsPbBr_(3)QDs,while the SiO_(2)and PDMS layers serve as protective barriers against moisture,heat,and radiation.The resulting CsPbBr_(3)@Cs_(4)PbBr_(6)/SiO_(2)/PDMS flexible films exhibit a high photoluminescence quantum yield of 85%,outstanding mechanical flexibility,and remarkable durability under stretching,bending,and compressing.Moreover,the films retain excellent emission stability under elevated temperatures,prolonged X-ray irradiation,and extended water immersion.X-ray imaging evaluations further demonstrate a spatial resolution of 12 lp/mm,enabling distortion-free imaging of curved objects,while their superior water resistance allows for long-term underwater X-ray imaging.This work highlights the critical role of hierarchical encapsulation in balancing luminescence efficiency and environmental stability,offering a viable pathway toward practical high-performance flexible perovskite scintillators. 展开更多
关键词 multilevel encapsulation CsPbBr_(3)quantum dots flexible scintillator environmental robustness X-ray imaging
原文传递
UV-curable,Transparent,and Low Volume-shrinkage Silicones for Efficient Mini-LED Encapsulation
3
作者 Zi-Hua Zhang Juan Ye +2 位作者 Wei-Shan Wen Qing-Hong Luo Hong-Ping Xiang 《Chinese Journal of Polymer Science》 2026年第2期599-610,I0019,共13页
Mini light-emitting diodes(Mini-LEDs)show great application potential in high-end displays owing to their superior pixel density,brightness,responsiveness,and efficiency.However,current packaging materials for Mini-LE... Mini light-emitting diodes(Mini-LEDs)show great application potential in high-end displays owing to their superior pixel density,brightness,responsiveness,and efficiency.However,current packaging materials for Mini-LEDs are predominantly thermally cured,which is energy-and time-consuming and can adversely affect electronic components.In this study,a novel UV-curable silicone resin containing phenyl,disulfide,and acryloyl groups(SPASR)is developed from commercially available siloxanes.The resin exhibits a refractive index(n_(d))higher than 1.5,and it can be cured within 30 s under UV irradiation.After curing,it exhibits an optical transparency exceeding 92%,a lap adhesion strength of up to1.84 MPa,and good thermostability(T_(5%)>265℃).Notably,the volume shrinkage is less than 4.83%,attributed to the release of photopolymerization stress via UV-induced disulfide metathesis during UV curing.Mini-LEDs encapsulated with this resin show luminescence properties comparable to those of conventional thermally-cured sealants,and show excellent sealability wihtout visible penetration after being immersed in red ink for 12 h.Consequently,these excellent properties make the SPASR resin an ideal candidate for microelectronic encapsulation,offering a more reliable and efficient solution for the electronics industry. 展开更多
关键词 UV-curing technology Silicone resin Mini-LEDs encapsulants Low volume shrinkage Disulfide metathesis
原文传递
A review of encapsulation methods and geometric improvements of perovskite solar cells and modules for mass production and commercialization 被引量:1
4
作者 Wending Yang Yubo Zhang +2 位作者 Chengchao Xiao Jingxuan Yang Tailong Shi 《Nano Materials Science》 2025年第6期790-809,共20页
Owing to the outstanding optoelectronic properties of perovskite materials,perovskite solar cells(PSCs)have been widely studied by academic organizations and industry corporations,with great potential to become the ne... Owing to the outstanding optoelectronic properties of perovskite materials,perovskite solar cells(PSCs)have been widely studied by academic organizations and industry corporations,with great potential to become the next-generation commercial solar cells.However,critical challenges remain in preserving high efficiency practical large-scale commercialized PSCs:a)the long-term stability of the cell materials and devices,b)lead leakage,and c)methods to scale the cells for larger area applications.This paper summarizes the prior-art strategies to address the above challenges,including the latest studies on the traditional glass-glass and thin-film encapsulation methods to better improve the reliability of PSCs,new technologies for preventing lead leakage,and geometric improvement strategies to enhance the reliability,efficiency,and performance of perovskite solar modules(PSMs).Through these strategies,the device achieved enhanced performance in long-term stability tests.The encapsulation resulted in a high lead leakage inhibition rate of up to 99%,and the PSMs possessed a geometric fill factor of 99.6%and a power conversion efficiency(PCE)of 20.7%.The dramatic improvement of efficiency and reliability of perovskite solar cells and modules indicate the great potential for mass production and commer-cialization of perovskite solar applications in the near future. 展开更多
关键词 Perovskite solar modules encapsulation Geometric improvement Stability COMMERCIALIZATION
在线阅读 下载PDF
Review on high-temperature macroencapsulated phase change materials:Encapsulation strategy,thermal storage system,and optimization 被引量:1
5
作者 Yi Yang Xiaojie Guo +2 位作者 Meng Liu Hang Yang Deqiu Zou 《Journal of Energy Chemistry》 2025年第5期324-359,共36页
High-temperature phase change materials(PCMs)have attracted significant attention in the field of thermal energy storage due to their ability to store and release large amounts of heat within a small temperature fluct... High-temperature phase change materials(PCMs)have attracted significant attention in the field of thermal energy storage due to their ability to store and release large amounts of heat within a small temperature fluctuation range.However,their practical application is limited due to problems such as leakage,corrosion,and volume changes at high temperatures.Recent research has shown that macroencapsulation technology holds promise in addressing these issues.This paper focuses on the macroencapsulation technology of high-temperature PCMs,starting with a review of the classification and development history of high-temperature macroencapsulatd PCMs.Four major encapsulation strategies,including electroplating method,solid/liquid filling method,sacrificial material method,and powder compaction into sphere method,are then summarized.The methods for effectively addressing issues such as corrosion,leakage,supercooling,and phase separation in PCMs are analyzed,along with approaches for improving the heat transfer performance,mechanical strength,and thermal cycling stability of macrocapsules.Subsequently,the structure and packing arrangement optimization of macrocapsules in thermal storage systems is discussed in detail.Finally,after comparing the performance of various encapsulation strategies and summarizing existing issues,the current technical challenges,improvement methods,and future development directions are proposed.More attention should be given to utilizing AI technology and reinforcement learning to reveal the multiphysics-coupled heat and mass transfer mechanisms in macrocapsule applications,as well as to optimize material selection and encapsulation parameters,thereby enhancing the overall efficiency of thermal storage systems. 展开更多
关键词 Phase change materials Macroencapsulation Macrocapsules Thermal energy storage encapsulation strategy
在线阅读 下载PDF
Encapsulation for efficient cryopreservation
6
作者 Kashan Memon Bing Zhang +1 位作者 Muhammad Azam Fareed Gang Zhao 《Frigid Zone Medicine》 2025年第2期73-80,共8页
Cryopreservation is a fundamental technology in biomedical research,regenerative medicine,and tissue engineering,enabling the long-term storage of cells,tissues,and organs.However,its effectiveness is limited by chall... Cryopreservation is a fundamental technology in biomedical research,regenerative medicine,and tissue engineering,enabling the long-term storage of cells,tissues,and organs.However,its effectiveness is limited by challenges such as intracellular ice formation,cryoprotectant toxicity,and reduced post-thaw viability.This review explores the crucial role of encapsulation in enhancing cryopreservation efficiency,with a focus on recent advances in materials science,bioengineering,and cryobiology.Emerging technologies,such as nanotechnology and stimuli-responsive polymers,are transforming encapsulation strategies.Innovations such as microfluidic systems offer precise control over cooling rates and cryoprotectant distribution,thereby mitigating conventional limitations.The review also addresses current obstacles related to scaling up encapsulation processes and ensuring the long-term biocompatibility and stability of preserved specimens.By synthesizing recent findings,this work provides a comprehensive resource for researchers and clinicians seeking to enhance biopreservation techniques and their applications in contemporary medicine and biotechnology.Finally,the review identifies critical knowledge gaps that must be addressed to improve the efficacy of cryopreservation strategies and advance their clinical translation. 展开更多
关键词 CRYOPRESERVATION encapsulation HYDROGELS BIOMATERIALS tissue engineering regenerative medicine NANOTECHNOLOGY smart polymers
原文传递
Selective encapsulation of azo compounds by tetracationic cyclophane in water and photo-controlled reversible release
7
作者 Baoqi Wu Rongzhi Tang +5 位作者 Zhi-Wei Li Feng Lin Zongyu Sun Huanyu Xia Lin Jiang Yu Tan 《Chinese Chemical Letters》 2025年第9期360-366,共7页
Many azo compounds and their intermediates are toxic and have been linked to various health issues,representing a growing global problem.Molecular engineering for selective encapsulation of azobenzene compounds is cri... Many azo compounds and their intermediates are toxic and have been linked to various health issues,representing a growing global problem.Molecular engineering for selective encapsulation of azobenzene compounds is critical,given their significant use in smart materials and prevalence as environmental micropollutants released from the food and dye industries.However,the current host molecules catering to azobenzene compounds are mainly limited to cyclodextrins,pillar[n]arenes and cucurbit[n]urils,demonstrating a moderate affinity.This report describes that a novel 3,3'-bipyridinium-based cyclophane was capable of encapsulating anionic azobenzene compounds in water with high binding affinity and pH stability through electrostatic attraction-enhanced mechanism,surpassing the extensively reported supramolecular systems.1D&2D NMR experiments,UV-vis spectrum,X-ray crystallography and computational modeling were carried out to understand the host-vip complexation.It's worth noting that the tetracationic cyclophane exhibited good selective and anti-interference encapsulation properties in binary,ternary and seawater systems.Furthermore,upon UV/white light irradiation,the reversible conversion between(E)-4,4'-azobisbenzoate and(Z)-4,4'-azobisbenzoate triggers the dissociation/recomplexation of the host-vip complex within 3 min.This reversible photo-switchable(E)-disodium 4,4'-azobisbenzoateBPy-Box^(4+)supramolecular system holds promise for designing novel materials for extraction/release of azo compounds and other small smart materials. 展开更多
关键词 CYCLOPHANE MACROCYCLE Molecular recognition Photo-switchable encapsulation
原文传递
Hesperidin encapsulation in mung bean isolate protein-dextran conjugate-stabilized nanoemulsions:Preparation and characterization
8
作者 Zixi Xue Xianrong Xiang +3 位作者 Jiaying Tang Wen Qin Guohua Zhang Qing Zhang 《Grain & Oil Science and Technology》 2025年第4期247-260,共14页
Encapsulation and protection of hesperidin(HES)in mung bean protein isolate(MPI)-dextran(DX)conjugatestabilized nanoemulsions(MDC NEs)were investigated in this study.The degree of grafting of MDC prepared by a dry-hea... Encapsulation and protection of hesperidin(HES)in mung bean protein isolate(MPI)-dextran(DX)conjugatestabilized nanoemulsions(MDC NEs)were investigated in this study.The degree of grafting of MDC prepared by a dry-heating method reached 39.70%±0.01% under the optimal conditions of MPI/DX mass ratio 1:2.3,reaction temperature 58.8℃,and reaction time 4 d.Moreover,the analyses of Fourier infrared spectroscopy,intrinsic fluorescence spectroscopy,surface hydrophobicity,and thermal stability further confirmed the covalent grafting of dextran onto MPI molecules.When encapsulated in MDC NEs at 80 MPa for three times by highpressure homogenization,the encapsulation efficiency and loading capacity of HES were 63.62%±0.01%and 0.40±0.00 g/g,respectively.The encapsulated HES exhibited higher antioxidant activity and stronger light and storage stability than the free HES.Additionally,the incorporation of HES inhibited the formation of lipid peroxides in the nanoemulsions.The findings suggest that glycosylation combined with high-pressure homogenization is an effective strategy for enhancing the stability of MPI-based emulsions and improving their encapsulation of HES.This study provides a promising approach for the development of innovative food and beverage products based on MPI emulsions or new materials for encapsulating fat-soluble bioactive compounds. 展开更多
关键词 Mung bean protein isolate-dextran conjugate NANOEMULSIONS encapsulation HESPERIDIN Stability
在线阅读 下载PDF
A comprehensive review on the nutritional composition,bioactive potential,encapsulation techniques,and food system applications of guava(Psidium guajava L.)leaves
9
作者 Anjali Sahal Siddhant Chaudhary +5 位作者 Afzal Hussain Shubhangi Arora Ankita Dobhal Waseem Ahmad Vinod Kumar Sanjay Kumar 《Grain & Oil Science and Technology》 2025年第1期64-74,共11页
Guava(Psidium guajava L.),a plant belonging to the Myrtaceae family,holds significant medicinal and nutritional values.Leaves of the plant are described to be elliptical with a dark green color and are utilized in the... Guava(Psidium guajava L.),a plant belonging to the Myrtaceae family,holds significant medicinal and nutritional values.Leaves of the plant are described to be elliptical with a dark green color and are utilized in the treatment of gastrointestinal and respiratory issues along with increasing the platelet count in patients suffering from dengue.In this review paper,the nutritional composition and bioactive compounds of guava leaves,including proteins,vitamins,minerals,and polysaccharides,have been reviewed.The methods of extraction of bioactive compounds from guava leaves and their bioactivities,including antioxidant,anti-diabetic,and anti-cancer potential,have been explored.Further,encapsulation techniques for improving the transport of bioactive compounds and living cells into foods have been studied.The application of guava leaves in different food systems such as herbal tea,pork sausage,chocolates,jelly,meals for chickens,functional beverages,and as antibacterial agents in food preservatives has also been investigated.The findings of this review illustrated that the phytochemicals present in guava leaves showed excellent antimicrobial and antioxidant properties.Encapsulation appears to be a promising technique for improving the stability,bioavailability,and controlled release of bioactive chemicals extracted from guava leaves.Different methods for the encapsulation of bioactive compounds employed and applied in distinct food systems showed preservation of phytochemicals,improved bioactivities,and nutritional values.Overall,this review paper demonstrated how guava leaves,an abundant source of bioactive compounds,can be used as a multipurpose component to create functional foods,edible coatings,and active packaging to enhance the nutritional,antioxidant,and antimicrobial properties of various food systems that have qualities that promote health. 展开更多
关键词 Psidium guajava L. BIOAVAILABILITY EXTRACTION encapsulation Food system
在线阅读 下载PDF
Site-specific surface amination strategy facilitates biomimetic encapsulation of enzymes within hydrogen-bonded organic framework
10
作者 Haoquan Huang Haiting Chen +8 位作者 Xinran Dong Yanbin Xu Anlian Huang Qiaoyi Cen Huairou Zhu Guosheng Chen Wei Yi Siming Huang Gangfeng Ouyang 《Chinese Chemical Letters》 2025年第9期372-378,共7页
Hydrogen-bonded framework(HOF) offers an attractive platform to encapsulate enzymes and stabilize their conformation,due to the advantages of mild synthesis conditions,tailorable pore structure,and backbone biocompati... Hydrogen-bonded framework(HOF) offers an attractive platform to encapsulate enzymes and stabilize their conformation,due to the advantages of mild synthesis conditions,tailorable pore structure,and backbone biocompatibility.However,the efficiency of this HOF approach relies on the interfacial interactions between enzyme vip and the ligand precursors,limiting its adaptability to enzymes with varying surface chemistry property.In this study,we report a site-specific surface modification strategy to positively tailor the enzyme surface charge,facilitating the biomimetic encapsulation of enzymes within HOF in situ.Both experimental results and computational simulation reveal that site-specific amination of enzyme surface's acidic residues contributes to the interfacial accumulation of carboxylic ligand precursors in aqueous solutions via synergistic electrostatic and hydrogen bonding interactions.This substantially facilitates the in situ growth of porous HOF surrounding the aminated enzyme biotemplates,with up to 100% enzyme loading efficiency.The resultant hydrogen-bonded biohybrid framework(HBF) retains high biocatalytic functions while exhibiting exceptional stability under harsh conditions.By leveraging the marked catalytic activity of GOx-NH_(2)@HBF-1 and a H_(2)O_(2)-sensitive QD,a highly sensitive glucose fluorescence sensor is fabricated with a wide linear range(5-2000 μmol/L) and a low quantification limit of 5 μmol/L.This work presents a simple yet effective enzyme surface engineering approach for integrating enzyme into HOF,opening new avenues for the construction of multifunctional HOF biocomposites. 展开更多
关键词 Enzyme immobilization Chemical modification Hydrogen-bonded organic framework In situ encapsulation Sensor
原文传递
Single-molecule dynamic dissociation and polymerization-governed in situ repair and encapsulation for high-performance perovskite solar cells
11
作者 Xianfei Cao Yong Qi +6 位作者 Wenshuai Zhao Zengyao Guo Tong Hu Zhengyang Gao Wenchao Han Lei Li Shufen Zhang 《Journal of Energy Chemistry》 2025年第10期923-930,共8页
Despite the ongoing increase in the efficiency of perovskite solar cells(PSCs),residual lead iodide(PbI2and moisture sensitivity issues continue to constrain their further commercialization.Herein,we propose a thermal... Despite the ongoing increase in the efficiency of perovskite solar cells(PSCs),residual lead iodide(PbI2and moisture sensitivity issues continue to constrain their further commercialization.Herein,we propose a thermally mediated in situ repair and encapsulation strategy to construct high-performance PSCs by incorporating piperazine thioctic acid salt(TAPPZ)as a dopant into the perovskite precursor Thermally dissociated piperazine(PPZ)from TAPPZ integrates microcrystals to form larger grain(>2000 nm),while the carboxylic acid in thioctic acid(TA)and the amine salt in TAPPZ synergistically passivate and transform PbI_(2),significantly reducing its residual amount.Additionally,TAPPZ undergoe thermal self-crosslinking during perovskite annealing,enabling melt-polymerization to form in situ encapsulation for enhanced water resistance.The TAPPZ-incorporated device achieves a remarkable efficiency of 25.65% and exhibits excellent operational stability,retaining over 90% of its initial efficiency after 2000 h under ambient conditions(20-30℃,20%-30% relative humidity).This study provide new insights into the construction of high-performance perovskite solar cells by designing and synthe sizing multifunctional single molecules for in situ repair and encapsulation of perovskites. 展开更多
关键词 Perovskite solar cells Multifunctional single-molecule Piperazine thioctic acid salt In situ repair In situ encapsulation
在线阅读 下载PDF
水热合成ZSM-22封装Ni及选择性催化炔醇加氢
12
作者 王学林 毕文涛 +2 位作者 曲炜 王从新 田志坚 《化工进展》 北大核心 2026年第1期247-257,共11页
以硅溶胶为硅源,1,6-己二胺为有机模板剂,氢氧化钾为碱源,硝酸镍为镍源,四乙烯五胺为有机胺配体,ZSM-22分子筛为晶种,采用水热法以及后续的焙烧和还原合成了Ni负载量为0.06%~0.34%的ZSM-22分子筛封装Ni催化剂(Ni@ZSM-22)。采用X射线衍射... 以硅溶胶为硅源,1,6-己二胺为有机模板剂,氢氧化钾为碱源,硝酸镍为镍源,四乙烯五胺为有机胺配体,ZSM-22分子筛为晶种,采用水热法以及后续的焙烧和还原合成了Ni负载量为0.06%~0.34%的ZSM-22分子筛封装Ni催化剂(Ni@ZSM-22)。采用X射线衍射、N2物理吸附、扫描电子显微镜、透射电子显微镜、X射线光电子能谱和H_(2)-程序升温还原表征了催化剂的物相、织构性质、Ni颗粒尺寸分布和落位。结果表明,样品均具有结晶度良好的ZSM-22分子筛相、相互穿插的梭形棒形貌,粒径分布均匀的高分散Ni颗粒被封装在分子筛晶粒的内部,85%以上Ni颗粒粒径小于2nm,Ni物种以金属态Ni^(0)和氧化态Ni^(δ+)(Ni—O—Si)两种形式共存。考察了催化剂的1,4-丁炔二醇加氢性能,催化剂上主产物是1,4-丁烯二醇,其中顺式烯醇占烯醇总量的94%以上。结合表征结果和产物分布,认为优异的烯醇选择性与ZSM-22分子筛孔道的空间限域作用以及Ni^(δ+)的存在有关。 展开更多
关键词 水热 分子筛 封装 催化剂 1 4-丁炔二醇 加氢 1 4-丁烯二醇
在线阅读 下载PDF
Effect of Experimental Parameters on the Encapsulation of Insulin-loaded Poly(lactide-co-glycolide) Nanoparticles Prepared by a Double Emulsion Method 被引量:3
13
作者 潘妍 赵会英 +3 位作者 徐晖 魏刚 郝劲松 郑俊民 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第1期38-41,共4页
Insulin-loaded poly(lactide-co-glycolide) nanoparticles (INS-PLGA-NPs) were prepared by a double emulsion method (w/o/w), using ethyl acetate as organic solvent and poloxamer188 as emulsifier. Experimental parameter... Insulin-loaded poly(lactide-co-glycolide) nanoparticles (INS-PLGA-NPs) were prepared by a double emulsion method (w/o/w), using ethyl acetate as organic solvent and poloxamer188 as emulsifier. Experimental parameters such as the emulsifier and PLGA concentrations, the pH and concentration of the insulin solution, the solvent evaporation method and PVA in the internal phase were investigated for the encapsulation efficiency. The results indicated that higher emulsifier concentration, relatively less amount of PLGA and lower insulin concentration would increase the entrapment of insulin. Furthermore, pH of insulin solution approaching to pI (5.3), adding some PVA to the internal phase and a shorter evaporation time helped to enhance the incorporation efficiency of insulin. Optimized preparation parameters led to nanoparticles with well-defined characteristics such as an average size around 149.6 nm, a polydispersity lower than 0.1 and high encapsulation efficiency up to 42.8%. 展开更多
关键词 NANOPARTICLES PLGA encapsulation
暂未订购
Run by Run Control of Time-pressure Dispensing for Electronics Encapsulation 被引量:5
14
作者 Cong-Ping Chen Han Ding 《International Journal of Automation and computing》 EI 2008年第4期419-424,共6页
To alleviate the influence of gas compressibility on the process performance of time-pressure dispensing for electronics encapsulation,a predictive model is developed based on power-law fluid to estimate the encapsula... To alleviate the influence of gas compressibility on the process performance of time-pressure dispensing for electronics encapsulation,a predictive model is developed based on power-law fluid to estimate the encapsulant amount dispensed.Based on the simple and effective model,a run by run (RbR) supervisory control scheme is delivered to compensate the variation resulting from gas volume change in the syringe.Both simulation and experiment have shown that the dispensing consistency has been greatly improved with the model-based RbR control strategy developed in this paper. 展开更多
关键词 Time-pressure dispensing predictive model run by run (RbR) control electronics encapsulation.
在线阅读 下载PDF
与刀具共形封装的PVDF压电薄膜切削力传感器非线性度研究
15
作者 刘蒙霖 林铁 +5 位作者 沈宏 王旭东 孟祥建 曹华军 陶桂宝 褚君浩 《工具技术》 北大核心 2026年第2期124-132,共9页
实时、准确获取刀具切削力,实现在线监测刀具磨破损和加工状态,是智能与精密加工的一项关键内容。聚偏氟乙烯(PVDF)压电薄膜传感器因其可实现与刀具共形封装、不削弱刀具强度,成为研究热点。但传感器对切削力响应非线性会减小切削力测... 实时、准确获取刀具切削力,实现在线监测刀具磨破损和加工状态,是智能与精密加工的一项关键内容。聚偏氟乙烯(PVDF)压电薄膜传感器因其可实现与刀具共形封装、不削弱刀具强度,成为研究热点。但传感器对切削力响应非线性会减小切削力测量范围,限制刀具使用场景。采用欧拉—伯努利悬臂梁模型,分析与刀具共形封装的PVDF压电薄膜传感器对切削力响应非线性的影响因素,获得二阶非线性响应解析式,并通过准静态加载实验对理论模型进行验证。同时,基于解析式讨论抑制响应非线性的方法。结果表明,二阶非线性主要来源于金属屏蔽层对压电薄膜产生的面外压力。本文工作可以为PVDF压电薄膜的传感器设计提供参考。 展开更多
关键词 切削力传感器 PVDF压电薄膜 非线性 共形封装
在线阅读 下载PDF
凉山乌洋芋花青素水凝胶制备及其特性分析
16
作者 尹琳 左清吕 +5 位作者 马逸飞 张子豪 杨潇 阳辉蓉 曾英杰 巩发永 《食品工业科技》 北大核心 2026年第4期69-77,共9页
目的:系统研究乌洋芋花青素的高效提取工艺,构建明胶/结冷胶复合水凝胶递送体系,并阐明其在胃肠消化环境中的稳定性与生物安全性。方法:采用酸性乙醇法提取花青素并构建水凝胶体系;通过流变仪和质构分析仪表征不同浓度明胶-结冷胶复合... 目的:系统研究乌洋芋花青素的高效提取工艺,构建明胶/结冷胶复合水凝胶递送体系,并阐明其在胃肠消化环境中的稳定性与生物安全性。方法:采用酸性乙醇法提取花青素并构建水凝胶体系;通过流变仪和质构分析仪表征不同浓度明胶-结冷胶复合水凝胶(配比8:2,m/m)的表观黏度、凝胶强度及包埋效率;利用体外模拟消化模型评估花青素在胃液(pH3.0,2 h)和肠液(pH6.8,6 h)中的稳定性和溶胀特性,并通过CCK-8法检测水凝胶对IEC-6细胞增殖的影响。结果:酸性乙醇辅助提取使花青素得率达57.20 mg/g,显著高于常规浸提法(P<0.05)。0.5%复合水凝胶(壁材为质量比8:2的明胶-结冷胶,芯材为乌洋芋花青素)呈现最优性能:凝胶强度21.4 g、表观黏度0.09 Pa·s及包埋率90.81%。花青素水凝胶在宽角频率范围内形成了稳定的三维网络结构,有效保证了花青素的包埋。储藏稳定性实验显示,4℃条件下花青素的降解显著低于37℃,且水凝胶在高温下表现出较好的稳定性。SEM图像显示,花青素复合水凝胶形成了典型的三维多孔网络结构,孔径主要分布在50~200μm之间。模拟消化实验进一步验证了水凝胶能有效延缓花青素的降解,并促进其在小肠中的缓释。CCK-8法实验表明,复合水凝胶几乎没有细胞毒性(P>0.05),证明其具有较高的安全性。结论:明胶/结冷胶复合水凝胶可显著提升乌洋芋花青素的胃肠稳定性与靶向递送效率,为其在功能食品开发中的应用提供理论支撑。后续需通过体内实验验证其生物利用度提升效果。 展开更多
关键词 乌洋芋 花青素 水凝胶 包埋 稳定性 生物相容性
在线阅读 下载PDF
ZSM-5分子筛限域镍铂团簇催化剂的制备及其烷烃芳构化性能
17
作者 吴鲁楠 师楠 +5 位作者 李骏 杨修洁 丑维超 娄斌 温福山 刘东 《石油学报(石油加工)》 北大核心 2026年第1期1-10,共10页
采用原位水热合成法将Ni和Pt封装在ZSM-5分子筛的孔道结构中,制备了Ni-Pt@ZSM-5催化剂,并以正己烷为原料,考察催化剂的芳构化性能。评价结果表明,Ni-Pt@ZSM-5催化剂展现出较高的芳构化活性,在反应温度400℃时,正己烷转化率达到97.64%,... 采用原位水热合成法将Ni和Pt封装在ZSM-5分子筛的孔道结构中,制备了Ni-Pt@ZSM-5催化剂,并以正己烷为原料,考察催化剂的芳构化性能。评价结果表明,Ni-Pt@ZSM-5催化剂展现出较高的芳构化活性,在反应温度400℃时,正己烷转化率达到97.64%,芳烃选择性达到81.29%。通过XRD、TEM和CO脉冲吸附等表征技术发现,由于受ZSM-5分子筛孔道结构的限制,NiPt团簇的粒径减小,金属分散度提高,这有助于活性NiPt位点的充分暴露。XPS、H_(2)-TPR、NH_(3)-TPD和Py-FTIR等表征结果表明,与负载型催化剂Ni-Pt/ZSM-5相比,Ni-Pt@ZSM-5的孔道内NiPt团簇与ZSM-5分子筛骨架之间的相互作用更强;此外,Ni-Pt@ZSM-5中的羟基化层状硅酸镍提供了更多的Lewis酸位点,从而调节了催化剂表面的酸性位点分布。 展开更多
关键词 分子筛限域 ZSM-5分子筛 正己烷 铂镍双金属 芳构化
在线阅读 下载PDF
陶瓷基复合储热材料的制备与动态高温热流作用下的性能研究
18
作者 何西波 王伟 帅永 《储能科学与技术》 北大核心 2026年第2期344-352,共9页
长周期、动态高温热流持续储/放热工况下,定形复合相变储热材料熔盐的泄漏量远大于稳定条件。本研究对陶瓷基复合相变材料的制备工艺与单元结构进行优化,以提升其在动态高温热流作用下的热循环稳定性。通过不锈钢空心球对皮瓤结构的球... 长周期、动态高温热流持续储/放热工况下,定形复合相变储热材料熔盐的泄漏量远大于稳定条件。本研究对陶瓷基复合相变材料的制备工艺与单元结构进行优化,以提升其在动态高温热流作用下的热循环稳定性。通过不锈钢空心球对皮瓤结构的球形陶瓷基储热单元进行二次封装,两者间采用碳粉降低热阻,进一步设计并完成连续12 h、400℃的高温热流作用下的实验测试以对比不同复合储热材料间的泄漏性。优化后的新型陶瓷基球形储热材料的质量衰减仅为0.73%,有效储热量衰减0.68%,且具备优异的传热速率,这归结于多孔陶瓷骨架强而有力的吸附力和传热,以及球形不锈钢外壳提供的均匀受热面积。此外,通过一系列实验评估新型复合相变储热材料在填充床潜热储热系统内部的热传输过程,系统完成储/放热的时间分别为27 min和14 min,整体的储/放热效率为71.4%,㶲效率为64.8%,同样高于硅藻土基相变储热单元与不锈钢直接封装熔盐的相变储热单元。研究结果可为定形复合相变材料在余热回收、光热利用等领域的实际应用提供重要的指导和参考。 展开更多
关键词 复合相变材料 泄漏性 封装 实验
在线阅读 下载PDF
壳聚糖添加量对壳聚糖-籼米淀粉二元基壬酸复合物的影响
19
作者 关皓天 黄永春 +3 位作者 唐湘毅 胡欣月 李子康 王成龙 《食品科学》 北大核心 2026年第3期67-78,共12页
为探究壳聚糖-淀粉二元复合物对风味分子壬酸的包埋机制及性能调控规律,本研究系统考察不同分子质量(50、200、500、1000 kDa)和质量分数(1%、1.5%、2%)的壳聚糖与淀粉形成的复合基质对壬酸包埋能力、包埋稳定性及复合物结构理化特性的... 为探究壳聚糖-淀粉二元复合物对风味分子壬酸的包埋机制及性能调控规律,本研究系统考察不同分子质量(50、200、500、1000 kDa)和质量分数(1%、1.5%、2%)的壳聚糖与淀粉形成的复合基质对壬酸包埋能力、包埋稳定性及复合物结构理化特性的影响。对复合凝胶进行质构分析发现,改变壳聚糖分子质量与质量分数可显著调控复合凝胶的质构特性:低至中等分子质量(50、200 kDa)组的硬度、咀嚼性随壳聚糖质量分数升高而降低,500 kDa组则呈上升趋势;流变学特性表明,添加壳聚糖可以增加复合凝胶的储能模量(G′)和损耗模量(G″),糊化温度的调控效果依赖于壳聚糖分子质量与添加量的共同作用,50 kDa壳聚糖以质量分数为1%时延迟糊化效果最优,200、500 kDa壳聚糖则以1.5%添加量效果最佳,1000 kDa壳聚糖在质量分数为2%时有最佳延迟糊化效果。X射线衍射分析显示,随壳聚糖添加量增加,复合物在7.8°、13°、20°处衍射峰更尖锐;短程有序性分析表明,官能团峰值发生移动但无新特征峰形成,证实分子间作用力发生改变;微观形貌呈现表面光滑、规则的蜂窝状结构;X射线光电子能谱验证了淀粉与壳聚糖的相互作用;热重分析结果表明,1.5%添加量下复合物残余量最大(27.91%,200 kDa组)。本研究可为开发高效风味分子包埋载体及优化食品风味稳定化技术提供理论依据。 展开更多
关键词 壳聚糖 淀粉 风味分子 包埋 复合物凝胶
在线阅读 下载PDF
弹性壁面附近气泡脉动非线性特性研究
20
作者 王寻 胡承昊 +2 位作者 李蕊 苏庆刚 邵朝晖 《振动与冲击》 北大核心 2026年第4期38-50,90,共14页
包膜气泡被广泛应用于医学超声成像和靶向送药等领域,掌握不同环境中包膜气泡的动力学特性具有重要意义。该研究对弹性壁面附近包膜气泡的动力学方程进行数值求解,基于计算结果研究了塑料、生物组织和铝三种壁面对气泡脉动的影响。研究... 包膜气泡被广泛应用于医学超声成像和靶向送药等领域,掌握不同环境中包膜气泡的动力学特性具有重要意义。该研究对弹性壁面附近包膜气泡的动力学方程进行数值求解,基于计算结果研究了塑料、生物组织和铝三种壁面对气泡脉动的影响。研究中借助庞加莱分析法和分岔图对气泡脉动非线性特性进行了重点讨论。研究表明与自由气泡相比,塑料和生物组织这类柔性壁面会使得气泡出现非线性分岔和混沌所需要的驱动声压幅度升高,而铝壁面这类硬质壁面则效果相反。由频率响应相关分析可知,柔性壁面会减弱气泡脉动混沌程度,且使得气泡谐振频率向高频偏移,而硬质壁面则会增强气泡脉动混沌程度,并降低气泡谐振频率。随着气泡与壁面距离的增加,塑料壁面附近的气泡脉动非线性程度增强,而铝壁面附近的气泡非线性程度减弱。但随着壁面厚度的增加,塑料壁面和铝壁面附近气泡脉动的非线性程度总体上均有所增强,且铝壁面附近气泡非线性程度的增强更为显著。另外,气泡到生物组织壁面的距离和生物组织壁面的厚度对气泡脉动影响较小。该研究为不同壁面附近包膜气泡脉动的控制提供了理论支持,有利于促进包膜气泡在多种场景下的应用。 展开更多
关键词 弹性壁面 包膜气泡 分岔图 非线性脉动
在线阅读 下载PDF
上一页 1 2 239 下一页 到第
使用帮助 返回顶部