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Room-temperature phosphorescence from purely organic materials 被引量:4
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作者 Yang Liu Ge Zhan +2 位作者 Zhi-Wei Liu Zu-Qiang Bian Chun-Hui Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第8期1231-1240,1467,共10页
Room-temperature phosphorescence(RTP) materials have attracted great attention due to their involvement of excited triplet states and comparatively long decay lifetimes.In this short review,recent progress on enhanc... Room-temperature phosphorescence(RTP) materials have attracted great attention due to their involvement of excited triplet states and comparatively long decay lifetimes.In this short review,recent progress on enhancement of RTP from purely organic materials is summarized.According to the mechanism of phosphorescence emission,two principles are discussed to construct efficient RTP materials:one is promoting intersystem crossing(ISC) efficiency by using aromatic carbonyl,heavyatom,or/and heterocycle/heteroatom containing compounds;the other is suppressing intramolecular motion and intermolecular collision which can quench excited triplet states,including embedding phosphors into polymers and packing them tightly in crystals.With aforementioned strategies,RTP from purely organic materials was achieved both in fluid and rigid media. 展开更多
关键词 Room-temperature phosphorescence purely organic material Intersystem crossing Non-radiation transition
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Analysis of radiometer effect on proof mass in purely gravitational orbit
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作者 刘红卫 王兆魁 张育林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期583-592,共10页
Spacecrafts with the pure gravity environment are of great significance in precision navigation, gravity field measurement for celestial bodies, and basic physics ex- periments. The radiometer effect is one of the imp... Spacecrafts with the pure gravity environment are of great significance in precision navigation, gravity field measurement for celestial bodies, and basic physics ex- periments. The radiometer effect is one of the important interfering factors on the proof mass in a purely gravitational orbit. For the gravity field measurement system based on the inner-formation flying, the relationship between the radiometer effect on the inner- satellite and the system parameters is studied by analytical and numerical methods. An approximate function of the radiometer effect suitable for the engineering computation and the correction factor are obtained. The analytic results show that the radiometer effect on the inner-satellite is proportional to the average pressure while inversely pro- portional to the average temperature in the outer-satellite cavity. The radiometer effect increases with the temperature difference in the cavity, and its minimum exists when the cavity radius increases. When the minimum of the radiometer effect arrives, the ratio of the cavity radius to the inner-satellite radius is 1.189 4. This constant is determined by the spherical cavity configuration and independent of the temperature and pressure distributions. When the ratio of the cavity radius to the inner-satellite radius is more than 10, it is believed that the cavity is large enough, the radiometer effect is approxi- mately proportional to the square of the inner-satellite radius, and the influence of the outer-satellite cavity radius on the radiometer effect can be ignored. 展开更多
关键词 purely gravitational orbit proof mass inner-formation flying system ra-diometer effect cavity radius
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Restrictions on Purely Kinetic K-Essence
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作者 YANG Rong-Jia QI Jing-Zhao YANG Bao-Zhu 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第10期296-298,共3页
We restrict purely kinetic k-essence.Assuming that the equation of state is a power law of the kinetic energy,i.e.w=w0Xα,we find thatαmust be positive to obtain accelerated phases,constrained from the conditions for... We restrict purely kinetic k-essence.Assuming that the equation of state is a power law of the kinetic energy,i.e.w=w0Xα,we find thatαmust be positive to obtain accelerated phases,constrained from the conditions for stability and causality.In this case the k-essence behaves like a phantom.We also study the evolutions of the equation of state and the speed of sound with numerical simulations. 展开更多
关键词 KINETIC purely restrict
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Existence of Localized Modes in a Purely Anharmonic Chain
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作者 WANG Shaofeng 《Chinese Physics Letters》 SCIE CAS CSCD 1995年第2期95-97,共3页
For a monatomic one-dimensional chain of particles interacting via a nearest-neighbor purely anharmonic potential of any even order(such a chain is called purely anharmonic chain),it is proved that there really exist ... For a monatomic one-dimensional chain of particles interacting via a nearest-neighbor purely anharmonic potential of any even order(such a chain is called purely anharmonic chain),it is proved that there really exist exact localized modes. 展开更多
关键词 HARMONIC purely EXISTENCE
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In Situ Observation of KB_(5) Crystal Growth Under Purely Diffusion Gel Systems by Holographic Interferometry
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作者 CHEN Wanchun SHEN Yunxue +2 位作者 MA Wenyi LI Ming CHEN Yansong 《Chinese Physics Letters》 SCIE CAS CSCD 1991年第9期469-471,共3页
KB_(5)O_(8).4H_(2)O(KB_(5))crystals have been grown in an agar-agar gel by temperature decrease method for simulating crystal growth in space.Nucleation and growth have been followed by interferometric holography.A co... KB_(5)O_(8).4H_(2)O(KB_(5))crystals have been grown in an agar-agar gel by temperature decrease method for simulating crystal growth in space.Nucleation and growth have been followed by interferometric holography.A concentration field surrounding the growing crystals was obtained and a Liesegang ring was observed.The pattern are visualized directly to reveal physical phenomena of purely diffusion crystal growth kinetics. 展开更多
关键词 DIFFUSION purely
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An Investigation of Purely Azimuthal Passive Localization and Position Adjustment in Attempted UAV Formation Flights
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作者 Qi Zhang Keren Sun Qiaozhen Zhang 《Journal of Applied Mathematics and Physics》 2023年第10期3075-3098,共24页
When a cluster of unmanned aerial vehicles (UAVs) is flying in formation, it is crucial to maintain the formation and not to be interfered by external electromagnetic wave signals. In order to maintain the formation, ... When a cluster of unmanned aerial vehicles (UAVs) is flying in formation, it is crucial to maintain the formation and not to be interfered by external electromagnetic wave signals. In order to maintain the formation, this paper proposes to use pure azimuth passive positioning to adjust the position of UAVs, i.e., certain UAVs in the formation transmit signals, the rest of the UAVs receive the signals passively, and extract the orientation information from them to adjust the position of the UAVs [1] [2] [3]. In this paper, the position adjustment problem of UAVs in “circular” formation flight under three models is investigated. To address the problem of “how to obtain the position of the receiving UAV when there are two UAVs with known numbers and evenly distributed on the circumference in addition to the UAV transmitting at the known center of the circle, and the rest of the UAVs with slight deviations in their positions are receiving the signals”, two purely mathematical geometric methods, namely, triangular localization method and polar co-ordinate method, are proposed respectively. We have determined the position of the receiving UAV;we have used the exhaustive method and the construction and disproof method to solve the problem of “how many UAVs are needed to transmit signals in order to realize the effective positioning of the UAVs when it is known that a certain UAV with a slight deviation in its position receives the signals emitted by two UAVs at the same time”, and the results show that: in addition to the known signals emitted by two UAVs, it is also necessary to transmit the signals emitted by two UAVs. The results show that in addition to the known two UAVs transmitting signals, two additional UAVs are required to transmit signals for precise po-sitioning. When the position of UAVs has deviation at the initial moment, the ideal approximation method and the target delimitation method are pro-posed, and the target of nine UAVs uniformly distributed on a circle of a spe-cific radius is achieved through several adjustments, after which the ad-vantages and disadvantages of each model are analyzed, and suggestions for improvement are put forward. The purely azimuthal passive localization method and the constructed model approach proposed in this paper can be extended to other fields, such as spacecraft formations in space and battle-ship formations at sea, as well as other formation flight position adjustment problems. 展开更多
关键词 Pure Azimuth Passive Positioning Unmanned Aerial Vehicle (UAV) Position Adjustment Electromagnetic Silence
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Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals
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作者 Wei-Lei Zhou Siwei Wang Yong Chen 《Science China Chemistry》 2025年第1期12-14,共3页
Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties^([1]).Particularly,two-dimensional(2D)materials with extremely high surface area an... Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties^([1]).Particularly,two-dimensional(2D)materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry^([2,3]). 展开更多
关键词 BONDS purely DIMENSIONAL
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Blastoids generated purely from embryonic stem cells both in mice and humans 被引量:2
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作者 Baojiang Wu Yanqiu Wang +4 位作者 Jia Yan Mengya Liu Xihe Li Fuchou Tang Siqin Bao 《Science China(Life Sciences)》 SCIE CAS CSCD 2024年第2期418-420,共3页
Dear Editor,Embryonic stem cells(ESCs)and trophoblast stem cells(TSCs)are derived from blastocysts(Lu et al.,2001).Blastocyst-like structures(blastoids)are self-assembled structures formed by a combination of ESCs and... Dear Editor,Embryonic stem cells(ESCs)and trophoblast stem cells(TSCs)are derived from blastocysts(Lu et al.,2001).Blastocyst-like structures(blastoids)are self-assembled structures formed by a combination of ESCs and TSCs(Rivron et al.,2018).To increase the success rate of blastoid formation and its similarity with the features of blastocysts,some reports showed that blastoid could also be derived from a combination of three cell lines,ESCs,TSCs,and extraembryonic endoderm cells(XENs),or novel type of stem cells(Sozen et al.,2018;Weatherbee et al.,2023:Wu et al.,2023;Zhang et al.,2023;Zhang et al.,2019). 展开更多
关键词 purely SIMILARITY
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Coupled modeling and analysis of radiometer effect and residual gas damping on proof mass in purely gravitational orbit 被引量:10
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作者 LIU HongWei WANG ZhaoKui ZHANG YuLin 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第4期894-902,共9页
Spacecrafts free of all but gravitational forces are important in precision navigation,gravity field measurement and basic scientific research.The Inner-formation Flying System,one kind of spacecrafts free of all but ... Spacecrafts free of all but gravitational forces are important in precision navigation,gravity field measurement and basic scientific research.The Inner-formation Flying System,one kind of spacecrafts free of all but gravitational forces,is used for gravitational field measurement with high precision.Restraining the interfering factors on the inner-satellite is one of the keys to gravitational field measurement.Radiometer effect and residual gas damping are both interfering forces on the inner-satellite caused by gas molecules.By analyzing the mechanism of the two forces,a coupled model for radiometer effect and residual gas damping was established,which contained the coupling term and reflected the actual force of gas molecules on the inner-satellite.The simulation results showed the coupling property of radiometer effect and residual gas damping:The actual force of gas molecules is directly proportional to the average pressure in the cavity and the largest cross-sectional area of the inner-satellite,but is inversely proportional to the square root of the average temperature in the cavity. 展开更多
关键词 purely gravitational orbit proof mass radiometer effect residual gas damping coupled modeling
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Negative refraction based on purely imaginary metamaterials 被引量:5
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作者 Yang-Yang Fu Ya-Dong Xu Huan-Yang Chen 《Frontiers of physics》 SCIE CSCD 2018年第4期237-245,共9页
By introducing a new mechanism based on purely imaginary metamaterials (PIMs), we reveal that bidirectional negative refraction and planar focusing can be obtained using a pair of PIM slabs, over- coming the unidire... By introducing a new mechanism based on purely imaginary metamaterials (PIMs), we reveal that bidirectional negative refraction and planar focusing can be obtained using a pair of PIM slabs, over- coming the unidirectional limit in parity-time (PT)-symmetric systems. Compared with PT-symmetric systems, which require two different types of materials, the proposed negative refraction can be realized using two identical media. In addition, asymmetric excitation with bidirectional total transmission is observed in our PIM system. Therefore, a new way to realize negative refraction with properties that are unavailable in PT-symmetrie systems is presented. 展开更多
关键词 negative refraction coherent perfect absorber LASER purely imaginary metamaterials
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Stimulus-responsive room temperature phosphorescence in purely organic luminogens 被引量:13
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作者 Jie Yang Manman Fang Zhen Li 《InfoMat》 SCIE CAS 2020年第5期791-806,共16页
Luminogens that exhibit stimulus-responsive room temperature phosphorescence(RTP)have attracted significant attention for their applications in a wide range of fields such as data storage,sensors,and bio-imaging.Howev... Luminogens that exhibit stimulus-responsive room temperature phosphorescence(RTP)have attracted significant attention for their applications in a wide range of fields such as data storage,sensors,and bio-imaging.However,very few such materials are known,partly because of the unclear internal mechanism.In this review,we summarize recent advances in the field of stimulusresponsive RTP in purely organic luminogens,focusing on their unique emission behaviors and internal mechanisms governing the phenomena.We also attempt to identify the relationship between the mechanism,luminogens,and possible applications. 展开更多
关键词 purely organic luminogens room temperature phosphorescence stimulus-responsive emission
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Purely Hom-Lie bialgebras 被引量:3
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作者 Liqiang Cai Yunhe Sheng 《Science China Mathematics》 SCIE CSCD 2018年第9期1553-1566,共14页
In this paper, we first show that there is a Hom-Lie algebra structure on the set of(σ, σ)-derivations of an associative algebra. Then we construct the dual representation of a representation of a Hom-Lie algebra.We... In this paper, we first show that there is a Hom-Lie algebra structure on the set of(σ, σ)-derivations of an associative algebra. Then we construct the dual representation of a representation of a Hom-Lie algebra.We introduce the notions of a Manin triple for Hom-Lie algebras and a purely Hom-Lie bialgebra. Using the coadjoint representation, we show that there is a one-to-one correspondence between Manin triples for Hom-Lie algebras and purely Hom-Lie bialgebras. Finally, we study coboundary purely Hom-Lie bialgebras and construct solutions of the classical Hom-Yang-Baxter equations in some special Hom-Lie algebras using Hom-O-operators. 展开更多
关键词 Horn-Lie algebras Manin triples purely Horn-Lie bialgebras classical Hom-Yang-Baxter equations
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Molecular uniting set identified characteristic(MUSIC): a promising strategy for purely organic RTP luminogens 被引量:1
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作者 Xiangfeng Shao 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第8期975-976,共2页
The room temperature phosphorescences(RTP)are of growing interest owing to their promising applications in material science and bioimaging.To date,the lumiogens showing persistent RTP effect mainly contain the noble... The room temperature phosphorescences(RTP)are of growing interest owing to their promising applications in material science and bioimaging.To date,the lumiogens showing persistent RTP effect mainly contain the noble metals which have the shortcomings such as high cost,potential toxicity.The exploration of metal free luminogens,i.e.,purely organic RTP luminogens,is thus of great importance for the community. 展开更多
关键词 RTP Molecular uniting set identified characteristic a promising strategy for purely organic RTP luminogens MUSIC
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Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete
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作者 SHI Yuqiong LI Jingyi +1 位作者 ZHANG Yang LI Li 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期65-78,共14页
In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive streng... In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive strength.In this study,505 groups of data were collected,and a new database of compressive strength of PFGC was constructed.In order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative analysis.The five machine learning models all showed good compressive strength prediction performance on PFGC.Among them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,respectively.While R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,respectively.The two models have high prediction accuracy and outstanding generalization ability.In order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 variables.These 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide dosage.Curing temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement concrete.The importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash. 展开更多
关键词 machine learning pure fly ash geopolymer compressive strength feature perception
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Microstructure and Mechanical Properties of Explosively Welded Nickel/Steel Composite Plate Interface
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作者 Li Yan Wang Guicheng +3 位作者 Zhang Wenbin Yang Haijuan Li Jucai Liu Cuirong 《稀有金属材料与工程》 北大核心 2025年第8期1971-1979,共9页
High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscop... High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscope,scanning electron microscope,electron backscatter diffraction,and mechanical property testing,and the microstructural features and mechanical properties of the explosive welding interface were explored.The results show that along the direction of explosive welding,the pure nickel N6/steel 45#composite plate interface gradually evolves from a flat bond to a typical wavy bond.The grains at the crests and troughs exhibit high heterogeneity,and the closer to the interface,the finer the grains.Recrystallization and low-stress deformation bands are formed at the bonding interface.Nanoindentation tests reveal that plastic deformation occurs in the interfacial bonding zone,and the nanohardness values in the crest regions are higher than that in the trough regions.The tensile strength of the N6/45#interface is 599.8 MPa,with an average shear strength of 326.3 MPa.No separation phenomenon is observed between N6 and 45#after the bending test. 展开更多
关键词 explosive welding pure nickel N6/steel 45#composite plate MICROSTRUCTURE NANOINDENTATION
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Error Bounds for Uniform Asymptotic Expansions-Modified Bessel Function of Purely Imaginary Order
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作者 Wei SHI Roderick WONG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第5期759-780,共22页
The authors modify a method of Olde Daalhuis and Temme for representing the remainder and coefficients in Airy-type expansions of integrals.By using a class of rational functions,they express these quantities in terms... The authors modify a method of Olde Daalhuis and Temme for representing the remainder and coefficients in Airy-type expansions of integrals.By using a class of rational functions,they express these quantities in terms of Cauchy-type integrals;these expressions are natural generalizations of integral representations of the coe?cients and the remainders in the Taylor expansions of analytic functions.By using the new representation,a computable error bound for the remainder in the uniform asymptotic expansion of the modified Bessel function of purely imaginary order is derived. 展开更多
关键词 Modified Bessel function of purely imaginary order Airy function Uniform asymptotic expansion Error bound
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Purely Inseparable Extensions and Ramification Filtrations
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作者 Hao Yu HU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2021年第1期35-58,共24页
In this article,we investigate the shift of Abbes and Saito’s ramification filtrations of the absolute Galois group of a complete discrete valuation field of positive characteristic under a purely inseparable extensi... In this article,we investigate the shift of Abbes and Saito’s ramification filtrations of the absolute Galois group of a complete discrete valuation field of positive characteristic under a purely inseparable extension.We also study a functoriality property for characteristic forms. 展开更多
关键词 Abbes and Saito’s ramification filtration purely inseparable extension characteristic form
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Another Look at the Kanmuryojukyo(“The Meditation on the Buddha of Infinite Life Sutra”)
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作者 Kenneth Lee 《Journal of Literature and Art Studies》 2025年第3期251-261,共11页
The Kanmuryojukyo(“The Meditation on the Buddha of Infinite Life Sutra”)is among the three principle canons of Pure Land Buddhism(Jpn.Jodo Shu and Jodo Shinshu)along with Amitayus Sutra and the Amitabha Sutra.Althou... The Kanmuryojukyo(“The Meditation on the Buddha of Infinite Life Sutra”)is among the three principle canons of Pure Land Buddhism(Jpn.Jodo Shu and Jodo Shinshu)along with Amitayus Sutra and the Amitabha Sutra.Although the original Sanskrit text was never found,it was translated into Chinese by a monk named Kalayasas in the 5th century and became an influential text in Mahayana Buddhism in East Asia with the help of commentaries written by notable Chinese scholars,such as Shandao in the 7th century.The sutra contains the story of Queen Vaidehi who is imprisoned by her murderous son Ajatasattu and visited by Shakyamuni Buddha in response to her prayer to be born in Amitabha’s pure land.Though in prison,the Buddha tells her how to be liberated and reborn in the pure land by meditating sixteen visualizations. 展开更多
关键词 Contemplation Sutra Amitayus Pure Land Buddhism Sukhavati Dharmakara
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Journal of Mathematical Research with Applications Guide for Authors
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《Journal of Mathematical Research with Applications》 2025年第3期F0003-F0003,共1页
Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Appli... Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad felds of sciences and technology,scientists and engineers interested in mathematics. 展开更多
关键词 applied mathematics MATHEMATICS mathematical research research papers pure mathematics journal overview
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Pure drug nanomedicines-where we are?
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作者 Yaoyao Lai Bing Xie +1 位作者 Wanting Zhang Wei He 《Chinese Journal of Natural Medicines》 2025年第4期385-409,共25页
Pure drug nanomedicines(PDNs)encompass active pharmaceutical ingredients(APIs),including macromolecules,biological compounds,and functional components.They overcome research barriers and conversion thresholds associat... Pure drug nanomedicines(PDNs)encompass active pharmaceutical ingredients(APIs),including macromolecules,biological compounds,and functional components.They overcome research barriers and conversion thresholds associated with nanocarriers,offering advantages such as high drug loading capacity,synergistic treatment effects,and environmentally friendly production methods.This review provides a comprehensive overview of the latest advancements in PDNs,focusing on their essential components,design theories,and manufacturing techniques.The physicochemical properties and in vivo behaviors of PDNs are thoroughly analyzed to gain an in-depth understanding of their systematic characteristics.The review introduces currently approved PDN products and further explores the opportunities and challenges in expanding their depth and breadth of application.Drug nanocrystals,drug-drug cocrystals(DDCs),antibody-drug conjugates(ADCs),and nanobodies represent the successful commercialization and widespread utilization of PDNs across various disease domains.Self-assembled pure drug nanoparticles(SAPDNPs),a next-generation product,still require extensive translational research.Challenges persist in transitioning from laboratory-scale production to mass manufacturing and overcoming the conversion threshold from laboratory findings to clinical applications. 展开更多
关键词 Pure drug nanomedicines Drug nanocrystals Drug-drug cocrystals Antibody-drug conjugates Drug nanoparticles Nanobodies
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