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chinese chemical Letters 2020年第3期31卷 697-700页

作者： Jian Li Qi-Long Hu Xue-Ping chen Ke-Qiang Hou Albert s.c.chan Xiao-Feng Xiong Guangdong Key Laboratory of chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China

An efficient asymmetric and enantio-swithchable organocatalytic[3+3]annulation reaction using MBH-2-naphthoates of nitroalkenes and 4-hydroxyquinolin-2(1H)-ones has been *** substituted tetrahydropyrano[3,2-c]qui noli nones scaffolds with two adjacent stereogenic centers are obtained with high yield(up to 95%yield)and good stereoselectivities(up to>20:1 dr and 96%ee)in an enantio-switchable ***,gram scale synthesis was achieved and the nitro group could easily transform into an amino group without any appreciable loss in the diastereo-and enantioselectivity.

关键词： Organocatalysis Asymmetric synthesis Enantioswitchable cinchona alkaloid Tetrahydropyran[3,2-c]quinolines

convergence,scalarization and continuity of Minimal solutions in set Optimization

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Journal of the Operations Research s.c.ety of china 2024年第3期12卷 773-793页

作者： Karuna c.s.Lalitha Department of Mathematics University of DelhiDelhiDelhi110007India Department of Mathematics University of Delhi South CampusNew DelhiDelhi110021India

The paper deals with the study of two different aspects of stability in the given space as well as the image space,where the solution concepts are based on a partial order relation on the family of bounded subsets of a real normed linear *** first aspect of stability deals with the topological set convergence of families of solution sets of perturbed problems in the image space and Painlevé–Kuratowski set convergence of solution sets of the perturbed problems in the given *** convergence in the given space is also established in terms of solution sets of scalarized perturbed *** s.c.nd aspect of stability deals with semicontinuity of the solution set maps of parametric perturbed problems in both the spaces.

关键词： Topological convergence Painlevé-Kuratowski convergence Upper semicontinuity Lower semicontinuity stability scalarization

Temperature correction for Thickness Measurements of Hot Rolled steel Plates

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Journal of Iron and steel Research International 2010年第12期17卷 23-29页

作者： c Gheorghies s.c.ndurache-Bota Faculty of sciences Dunarea de Jos University

Measuring the thickness of steel plates during the hot rolling process Is.c.ucial tor getnng me necessary feedback to obtain the desired values at room temperature. The dilatation and the phase transformations of steel occur during heating and subsequent cooling and rolling strongly influences the results of thickness measurements. The radiometrie method provides the necessary means for making real-time and fully automatized measurements of steel thickness during rolling, if only the temperature correction is precisely known and taken into consideration. This article proves that the experimental results.c.ncerning the relative variation of steel thickness and corresponding massthickness variation can be correctly explained by means of the theory of metal dilatation correlated with the theory of nuclear radiation absorption when passing through a metal or metallic alloy, s.c. as steel.

关键词： hot rolling dilatation phase transformation temperature correction attenuation

sources and Deficiency Diseases of Mineral Nutrients in Human Health and Nutrition:A Review

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Pedosphere 2014年第1期24卷 13-38页

作者： U.c.GUPTA s.c.GUPTA Agriculture and Agri-canada canada Crops and Livestock Research Centre The Department of Plastic surgery Loma Linda University

Mineral nutrients are fundamentally metals and other inorganic compounds. The life cycle of these mineral nutrients begins in soil, their primary source. soil provides minerals to plants and through the plants the minerals go to animals and humans; animal products are also the source of mineral nutrients for humans. Plant foods.c.ntain almost all of the mineral nutrients established as essential for human nutrition. They provide much of our skeletal structure, e.g., bones and teeth. They are critical to countless body processes by serving as essential co-factors for a number of enzymes. Humans.c.n not utilize most foods without critical minerals and enzymes responsible for digestion and absorption. Though mineral nutrients are essential nutrients, the body requires them in small, precise amounts. We require them in the form found in crops and they can be classified into three different categories： major, s.c.ndary, and micro or trace minerals. This.c.assification is based upon their requirement rather than on their relative importance. Major minerals s.c. as potassium （K） and phosphorus （P） are required in amounts of up to 10 g d-1. The daily requirement of s.c.ndary and micro minerals ranges from 400 to 1 500 mg d-1 and 45 ~tg d-1 to 11 mg d-1, respectively. To protect humans from mineral nutrient deficiencies, the key is to consume a variety of foods in modest quantities, s.c. as different whole grains, low fat dairy, and different meats, vegetables and fruits. For insurance purposes, a supplement containing various mineral nutrients.c.n be taken daily.

关键词： deficiency diseases deficiency symptoms origin recommended daily dose toxicity

Inverse methodology as applied to reconstruct local textile features from measured pressure field

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Journal of Materials science & Technology 2021年第12期71卷 241-247页

作者： s.Bancora c.Binetruy s.Advani comas.c.rdona Ecole centrale de Nantes Research Institute in Civil Engineering and Mechanics(GeM)UMR CNRS 618344321 Nantes Cedex 3France Department of Mechanical Engineering University of DelawareNewarkDelaware 19716USA

One can compute the final deformation of a known geometry under specific boundary conditions using the constitutive laws of mechanics that describe their stress strain *** s.c. cases the initial geometry is known,and all operators mapping the deformation are defined on the reference ***,there are situations in which the final configuration of a deformation might be known but not the *** inverse formulation allows one to determine the initial geometry of a domain,given its final deformation state,the material behavior law and a set of boundary *** the present work we propose a method to reconstruct the mesoscale geometry of a textile based on its mechanical response during *** do so,stress boundary conditions are acquired by means of a pressuresensitive *** adopting an appropriate material law,the thickness and width information of the yarns are deduced from the pressure field experienced by the compacted *** 3 D scanning techniques s.c. as.c.,the proposed method can be applied on any domain size,allowing long-range variability to be *** the best of the authors’knowledge,there are no previous works that use a pressure-sensitive film on a large domain to capture the input data for a shape *** example application serves as a demonstration of a methodology which could be applied to other classes of materials.

关键词： Textiles Pressure sensors Inverse method Digital twin Geometry reconstruction Hyperelasticity

Pore size Distribution of High Performance Metakaolin concrete

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Journal of Wuhan University of Technology(Materials science) 2002年第1期17卷 42-46页

作者： c.s.Poon s.c.Kou L.Lam Department of civil and structural Engineering The Hong Kong Polytechnic University Hong Kong China

The compressive strength, porosity and pore size distribution of high performance metakaolin (MK) concrete were investigated. concretes.c.ntaining 0,5% , 10% and 20% metakaolin were prepared at a water / cementitious material ratio ( W/c) of 0. 30. In parallel, concrete mixtures with the replacement of cement by 20% fly ash or 5 and 10% silica fume were prepared for comparison. The specimens were cured in water at 27℃ for 3 to 90 days. The results show that at the early age of curing (3 days and 7 days), metakaolin replacements increase the compressive strength, but silica fume replacement slightly reduces the compressive strength. At the age of and after 28 days , the compressive strength of the concrete with metakaolin and silica fume replacement increases. A strong reduction in the total porosity and average pore diameter were observed in the concrete with MK 20% and 10% in the first 7 days.

关键词： high performance concrete metakaolin pore size distribution

Zinc-oxide/PDMs.c.ad tapered fiber saturable absorber for passively mode-locked erbium-doped fiber laser

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chinese Phys.c. B 2021年第5期30卷 384-389页

作者： F D Muhammad s A s Husin E K Ng K Y Lau c A c Abdullah M A Mahdi Department of Phys.c. Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Wireless and Photonics Networks Research centre Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Electronics and Nanoengineering Tietotie 3Aalto University02150 EspooFinland

We propose and demonstrate a passively mode-locked erbium-doped fiber laser(EDFL)based on zinc-oxide/polydimethylsiloxane(ZnO/PDMs)saturable absorber(sA)that evanescently interacts with the light on a tapered *** ZnO/PDMs.c.mposite is.c.ated on the whole surface of the tapered fiber to guarantee the maximum efficiency of the sA device,with a measured insertion loss of 0.87 dB and a modulation depth of 6.4%.The proposed laser can generate soliton mode-locking operation at a threshold power of 33.07 *** generated output pulse yields a repetition rate and pulse width of 9.77 MHz and 1.03 ps,*** results indicate that the proposed ZnO/PDMs.c.ad tapered fiber could be useful as an efficient,compatible,and low-cost sA device for ultrafast laser applications.

关键词： zinc-oxide saturable absorber tapered fiber mode-locked fiber laser

chemical characteristics of aerosols at coastal station in Hong Kong.Ⅱ. Environmental behavior of trace elements during the April 1995 to April 1996

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Journal of Environmental sciences 2004年第2期16卷 212-221页

作者： K.s.Lam Z.L.cheng s.c.Kot c.W.Tsang Department of civil and structural Engineering the Hong Kong Polytechnic UniversityResearch Center for Eco-Environmental Sciences Chinese Academy of SciencesDepartment of Mechanical Engineering The Hong Kong University of Science & Technology Clear Water BayDepartment of Applied Biology and Chemical Technology the Hong Kong Polytechnic University Hung Hom Hong Kong ChinaBeijing 100085 ChinaHong Kong ChinaHung Hom Hong Kong China

An one-year of sampling aerosol program was.c.rried out during the period of April 1995 to April 1996 at coastal region, cape D′Aguilar, in Hong Kong. The trace element composition of aerosol particles(TsP and PM 10 ) were measured and analyzed by using the Instrumental Neutron Activation Analysis(INAA) and Inductive couple Plasma-Mass spectrometry(IcP-Ms) techniques. The results showed that the polluted elements s.c. as: V, Zn, As, Pb, cd, sb, I, se, Bi, with high enrichment factor(E.F) values, are derived from anthropogenic sources, while sc, Al, Fe, Mn, sm, La, sr are less than 10 in E.F, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V(V *) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. La/sm, Mn */V * and Bi/Al indicate that both TsP and PM 10 of La/sm ratios are mainly related to soil and dust, Mn */V * are probably represent fossil combustion and Bi/Al are possibly ass.c.ated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis(APcA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime.

关键词： TsP PM 10 trace elements enhancement factor element ratios seasonal variation factor analysis

Intralenticular metallic foreign body: a case report

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International Journal of Ophthalmology(English edition) 2011年第3期4卷 326-328页

作者： s.c.Reddy Department of Ophthalmology Faculty of MedicineUniversity of Malaya

A case of retained intralenticular iron piece with signs of mild anterior uveitis at the time of presentation is reported in a 45 year-old man. His vision improved with topical cycloplegics and corticosteroids. After six months, his vision deteriorated grossly due to cataract formation. He regained good vision following removal of foreign body, extracapsular extraction with posterior chamber intraocular lens implantation. This.c.se highlights the conservative management of the condition till the patient develops.c.taract resulting in visual disability; and good visual recovery following cataract surgery with intraocular lens implantation.

关键词： intralenticular foreign body anterior uveitis traumatic cataract penetrating eye injury

MHD graphene-polydimethylsiloxane Maxwell nanofluid flow in a squeezing channel with thermal radiation effects

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Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1269-1284页

作者： G.c.sHIT s.MUKHERJEE Department of Mathematics Jadavpur University

The magnetohydrodynamic (MHD) graphene-polydimethylsiloxane (PDMs) nanofluid flow between two squeezing parallel plates in the presence of thermal radiation effects is investigated. The energy efficiency of the system via the Bejan number is studied extensively. The governing partial differential equations are converted by using the similarity transformations into a set of coupled ordinary differential equations. The set of these converted equations is solved by using the differential transform method (DTM). The entropy generation in terms of the Bejan number, the coefficient of skin-friction, and the heat transfer rate is furthermore investigated under the effects of various phys.c.l parameters of interest. The present study shows that the Bejan number, the velocity and thermal profiles, and the rate of heat transfer decrease with a rise in the Deborah number De while the skin-friction coefficient increases. It is also observed that the entropy generation due to frictional forces is higher than that due to thermal effects. Thus, the study bears the potential application in powder technology as well as in biomedical engineering.

关键词： graphene-polydimethylsiloxane (PDMs) Maxwell fluid differential transform method (DTM) thermal radiation Bejan number