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A case Study of heat Transfer from hot Runner Mould to the Fix Platen of the Injection-moulding Machine

厦门大学学报（自然科学版） 2002年第S1期41卷 97-98页

作者： c h tan K S Lee School of Mechanical & Manufacturing Engineering Department of Mechanical Engineering National University of Singapore Singapore Polytec hnic SingaporeSingapore

In an injection moulding process, the parallelism b et ween the tie bars of the injection moulding machine is very important as it will affect the mould closing and clamping system. In recent years, more and more ho t runner systems are being applied in the moulding industry to save material and decrease the losses of injection pressure. heat transfer from hot runner system from the fixed half which is secured in the fix machine platen could transmit s o much heat that it may cause high temperature differential between the machine fix platen and moving platen. This will cause the tie bar to become unparallel. Part quality will be compromised and the wear of the tie bar will be excessive. Overhaul of the tie bar may be necessary after a short period of time which is c ostly. This raises the need to analyze the heat transfer from the hot runner sys tem to the machine fix platen and the methods of isolating or minimizing the hea t transfer. In this case study, a photo lens article mould was used. The mould w as built with a direct hot runner nozzle system. heat conduction from hot runner and machine screw to machine fix platen were studied based on either using high temperature heat insulating plate put in placed between the mould and the mould ing machine fix platen or drill cooling channels in the front mould clamping pla te. The high temperature insulator is very costly as it is made out of glass re inforced polymer composite material. Experimental results were obtained and anal yzed to find the best method to minimize the unwanted heat transfer using the ch eapest and most effective method.

关键词： injection moulding cooling hot runner system i njection moulding machine platen tie bar

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The symmetric space,strong isotropy irreducibility and equigeodesic properties

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Science china Mathematics 2024年第1期67卷 129-148页

作者： Ming Xu Ju tan School of Mathematical Sciences Capital Normal UniversityBeijing 100048China School of Microelectronics and Data Science Anhui University of TechnologyMa'anshan 243032China

A smooth curve on a homogeneous manifold G/h is called a Riemannian equigeodesic if it is a homogeneous geodesic for any G-invariant Riemannian *** homogeneous manifold G/h is called Riemannian equigeodesic,if for any x∈G/h and any nonzero y∈Tx(G/h),there exists a Riemannian equigeodesic c(t) with c(0)=x and ■(0)=*** two notions can be naturally transferred to the Finsler setting,which provides the definitions for Finsler equigeodesics and Finsler equigeodesic *** prove two classification theorems for Riemannian equigeodesic spaces and Finsler equigeodesic spaces,***,a homogeneous manifold G/h with a connected simply connected quasi compact G and a connected h is Riemannian equigeodesic if and only if it can be decomposed as a product of Euclidean factors and compact strongly isotropy irreducible ***,a homogeneous manifold G/h with a compact semisimple G is Finsler equigeodesic if and only if it can be locally decomposed as a product,in which each factor is Spin(7)/G2,G2/SU (3) or a symmetric space of compact *** results imply that the symmetric space and the strongly isotropy irreducible space of compact type can be interpreted by equigeodesic *** an application,we classify the homogeneous manifold G/h with a compact semisimple G such that all the G-invariant Finsler metrics on G/h are *** suggests a new project in homogeneous Finsler geometry,i.e.,to systematically study the homogeneous manifold G/h on which all the G-invariant Finsler metrics satisfy a certain geometric property.

关键词： equigeodesic equigeodesic space flag manifold orbit type stratification symmetric space strongly isotropy irreducible space

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The comparison Between Finite Element Analysis and Experimental Results of the cooling of Injection Moulds with hot Runner System

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厦门大学学报（自然科学版） 2002年第S1期41卷 110-111页

作者： Y F Sun K S Lee c h tan A Y c Nee Department of Mechanical Engineering National University of Singap oreDepartment of Mechanical Engineering National University of Singap oreSchool of Mechanical & Manufacturing EngineeringDepartment of Mechanical Engineering National University of Singapore SingaporeSingaporeSingapore Polytechnic Singapore Singapore

In an injection moulding process, the mould cooling s ystem is very important as an efficient and uniform cooling effect can improve b oth the productivity and part quality. Due to the complexity of the process, muc h research on the mould cooling analysis and cooling design optimization has bee n focused on the core and the cavity, excluding other systems of injection mould s. however, the runner system introduces a considerable amount of heat into the mould. In recent years, more and more hot runner systems are being applied in th e moulding industry to save material and decrease losses of injection pressure. This raises the need to include the hot runner system in the cooling analysis. I n this paper, a photo frame part was studied. The mould was built with a hot run ner system. Two thermal sensors were installed: one measures the temperature of lateral surface of hot runner nozzle; the other measures the plastic temperature from the core side. A pressure sensor was also installed to measure the pressur e of the core impression. cooling analysis was performed using ABAQUS, ananalysi s software based on the Finite Element Method (FEM). The assembly including core , cavity and plastic part was modeled. heat conduction from hot runner to cavity and from polymer melt to the mould and force convection on the cooling channel surfaces were studied. The natural convection between the ambient air and the ex terior mould surface was ignored. The simulations were adjusted with the experim ental results to find out the heat input from hot runner and its influence on mo uld cooling. Finally, the optimal cooling design and optimal injection condition were obtained.

关键词： injection moulding cooling injection mould cool ing finite element method hot runner

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Mechanical behavior and damage constitutive model of sandstone under hydro-mechanical (h-M) coupling

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International Journal of Mining Science and Technology 2024年第6期34卷 837-853页

作者： Tao tan chunyang Zhang Yanlin Zhao Xiaoshuang Li School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Safety and health in Metal Mines Maanshan 243000China Sinosteel Maanshan General Institute of Mining Research co. Ltd.Maanshan 243000China School of Resource&Environment and Safety Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Urban construction Changzhou UniversityChangzhouJiangsu 213164China

Underground engineering often passes through water-rich fractured rock masses,which are prone to fracture and instability under the long-term coupling of in-situ stress field and pore water(P-W)pressure,ultimately threatening the stability of underground *** order to explore the mechanical properties of rocks under h-M coupling,the corresponding damage constitutive(D-c)model has become the focus of *** the inadequacy of the current research on rock strength parameters,energy evolution characteristics and D-c model under h-M coupling,the mechanical properties of typical sandstone samples are discussed based on laboratory *** results show that the variation of characteristic stresses of sandstone under h-M coupling conforms to the normalized attenuation equation and Mohr-coulomb(Mc)*** P-W pressure mechanism of sandstone exhibits a dynamic change from softening effect to h-M fracturing *** closure stress is mainly provided by cohesive strength,while the initiation stress,damage stress,and peak stress are jointly dominated by cohesive strength and friction *** addition,residual stress is attributed to the friction strength formed by the bite of the fracture ***,the energy evolution characteristics of sandstone under h-M coupling were studied,and it was found that P-W pressure weakened the energy storage capacity and energy dissipation capacity of sandstone,and h-M fracturing was an important factor in reducing its energy storage ***,combined with energy dissipation theory and statistical damage theory,two types of D-c models considering P-W pressure are proposed accordingly,and the model parameters can be determined by four *** application results indicate that the proposed and modified D-c models have high reliability,and can characterize the mechanical behavior of sandstone under h-M coupling,overcome the inconvenience of existing D-c models due to excessive mechanical

关键词： h-M coupling Water-saturated sandstone Mechanical mechanism Energy evolution D-c model

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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang c.N.Wu h.Peng P.c.hen R.Li h.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

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An improved pulse coupled neural networks model for semantic IoT

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Digital communications and Networks 2024年第3期10卷 557-567页

作者： Rong Ma Zhen Zhang Yide Ma Xiping hu Edith c.h.Ngai Victor c.M.Leung School of Information Science and Engineering Lanzhou UniversityLanzhou 730000China School of Medical Technology Beijing Institute of TechnologyBeijing100081China Department of Electrical and Electronic Engineer The University of Hong KongHong Kong 999077China college of computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China Department of Electrical and computer Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in mobile data ***,with the rapid development of artificial intelligence,semantic communication has attracted great attention as a new communication ***,for IoT devices,however,processing image information efficiently in real time is an essential task for the rapid transmission of semantic *** the increase of model parameters in deep learning methods,the model inference time in sensor devices continues to *** contrast,the Pulse coupled Neural Network(PcNN)has fewer parameters,making it more suitable for processing real-time scene tasks such as image segmentation,which lays the foundation for real-time,effective,and accurate image ***,the parameters of PcNN are determined by trial and error,which limits its *** overcome this limitation,an Improved Pulse coupled Neural Networks(IPcNN)model is proposed in this *** IPcNN constructs the connection between the static properties of the input image and the dynamic properties of the neurons,and all its parameters are set adaptively,which avoids the inconvenience of manual setting in traditional methods and improves the adaptability of parameters to different types of *** segmentation results demonstrate the validity and efficiency of the proposed self-adaptive parameter setting method of IPcNN on the gray images and natural images from the Matlab and Berkeley Segmentation *** IPcNN method achieves a better segmentation result without training,providing a new solution for the real-time transmission of image semantic information.

关键词： Internet of things(IoT) Semantic information Real-time application Improved pulse coupled neural network Image segmentation

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hepatitis B virus genotypes in precision medicine of hepatitis Brelated hepatocellular carcinoma:Where we are now

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1097-1103页

作者： caecilia h c Sukowati Sri Jayanti Turyadi Turyadi David h Muljono claudio Tiribelli Eijkman Research center for Molecular Biology Research Organization for HealthNational Research and Innovation Agency of IndonesiaJakarta 10340Indonesia Liver cancer Unit Fondazione Italiana Fegato ONLUSTrieste 34149Italy Faculty of Medicine Hasanuddin UniversityMakassar 90245South SulawesiIndonesia Faculty of Medicine and health University of SydneySydney 2050Australia

hepatitis B virus(hBV)infection is a major player in chronic hepatitis B that may lead to the development of hepatocellular carcinoma(hcc).hBV genetics are diverse where it is classified into at least 9 genotypes(A to I)and 1 putative genotype(J),each with specific geographical distribution and possible different clinical outcomes in the *** diversity may be associated with the precision medicine for hBV-related hcc and the success of therapeutical approaches against hcc,related to different pathogenicity of the virus and host *** Editorial discusses recent updates on whether the classification of hBV genetic diversity is still valid in terms of viral oncogenicity to the hcc and its precision medicine,in addition to the recent advances in cellular and molecular biology technologies.

关键词： hepatitis B virus hepatocellular carcinoma Genotypes Pathogenesis Precision medicine

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Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.h.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

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An Isolable Phosphinogermylyne as a Synthon of One-coordinate GeⅠRadical

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chinese Journal of chemistry 2024年第7期42卷 736-742页

作者： Dongmin Wang haonan chen Yuhao he Xiaodan chen Li Zhang Gengwen tan Key Laboratory of Bioinorganic and Synthetic chemistry of Ministry of Education Guangdong Basic Research Center of Excellence for Functional Molecular EngineeringSchool of ChemistryIGCMESun Yat-Sen UniversityGuangzhouGuangdong 510275China School of Electronic Engineering Guangxi Universityof Science and TechnologyLiuzhouGuangxi 545000China college of chemistry and Material Jinan UniversityGuangzhouGuangdong 510632China Innovation center for chemical Science College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China Key Laboratory of Organosilicon chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhouZhejiang 311121China

Reduction of chlorogermylene MsFluindtBu-Gecl 1 with potassium graphite(Kc8)afforded putative germylyne radical MsFluindtBu-Ge 2 as confirmed by electron paramagnetic resonance(EPR)***,it slowly decayed via c—h bond activation at the fluorenyl moiety to yield a bis(germylene)3 at room *** using a Lewis base to stabilize the unoccupied p orbital at the GeⅠradical center,acyclic two-coordinate GeⅠradicals MsFluindtBu-Ge(IMe4)4(IMe4=1,3,4,5-tetramethyl-imidazolin-2-ylidene),MsFluindtBu-Ge(IiPr)5(IiPr=1,3-diisopropyl-4,5-dimethyl-imidazolin-2-ylidene),MsFluindtBu-Ge(PMe3)6 were isolated in crystalline *** unpaired electron in 4-6 mainly resides at the Ge 4p orbital as revealed by EPR spectroscopic studies and theoretical ***,facile ligand exchange of PMe3 in 6 with IMe4 and IiPr was observed to afford 4 and 5,***,phosphinogermylyne 6 reacted with PhEEPh(E=S,Se),4-tetrabutylphenylacetylene(Ar'cch),[cpMo(cO)3]2 and nBu3Snh to furnish germylenes MsFluindtBu-GeEPh(E=S 7,Se 8),MsFluindtBu-Gech=chAr'9,a germylyne complex MsFluindtBu-Ge≡Mo(cO)2cp 10 and a Ge(Ⅳ)compound MsFluindtBu-Geh2SnnBu311,*** reactivity studies demonstrate that 6 can act as a synthon of one-coordinate germylyne radical attributing to labile coordination of trimethylphosphine.

关键词： Phosphinogermylyne Germanium Radicals Donor-acceptor systems Radical reactions

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Deformable microlaser force sensing

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Light(Science & Applications) 2024年第6期13卷 1196-1209页

作者： Eleni Dalaka Joseph Shill Jonathan h.h.Booth Anna Popczyk Stefan R.Pulver Malte c.Gather Marcel Schubert centre of Biophotonics SUPASchool of Physics and AstronomyUniversity of St AndrewsNorth HaughSt AndrewsUK humboldt centre for Nano-and Biophotonics Department of ChemistryUniversity of CologneKölnGermany School of Psychology and Neuroscience University of St AndrewsSt Mary’s QuadSouth StreetSt AndrewsUK Institute for Bioengineering of catalonia BarcelonaSpain

Mechanical forces are key regulators of cellular behavior and function,affecting many fundamental biological processes such as cell migration,embryogenesis,immunological responses,and pathological *** force sensors and imaging techniques have been developed to quantify these otherwise invisible forces in single cells and in ***,current techniques rely heavily on high-resolution microscopy and do not allow interrogation of optically dense tissue,reducing their application to 2D cell cultures and highly transparent biological ***,we introduce DEFORM,deformable microlaser force sensing,a spectroscopic technique that detects sub-nanonewton forces with unprecedented spatio-temporal *** is based on the spectral analysis of laser emission from dye-doped oil microdroplets and uses the force-induced lifting of laser mode degeneracy in these droplets to detect nanometer *** validation by atomic force microscopy and development of a model that links changes in laser spectrum to applied force,DEFORM is used to measure forces in 3D and at depths of hundreds of microns within tumor spheroids and late-stage Drosophila *** furthermore show continuous force sensing with single-cell spatial and millisecond temporal resolution,thus paving the way for non-invasive studies of biomechanical forces in advanced stages of embryogenesis,tissue remodeling,and tumor invasion.

关键词： invasion otherwise hundreds

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