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排序方式: 共有294条查询结果,搜索用时 15 毫秒
1.
Anh Ha Lan Nhan Dang Duc Frew Russell Quynh Tran Minh 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3613-3621
Journal of Radioanalytical and Nuclear Chemistry - This research aimed to authenticate the geographical origin of imported fresh apples using isotopic techniques. The results show that the... 相似文献
2.
《印度化学会志》2023,100(2):100913
Owing to contribution of thermo-diffusion phenomenon in various engineering and industrial frame works, scientists have presented some exclusive investigations on this topic. In current research, the thermos-diffusion prospective of second grade material accounted by a moving cylinder have been predicted. The applications of Soret and Dufour effects based on the thermos-diffusion phenomenon is evaluated. The magnetic force and viscous dissipation effects are presented for the current flow model. Additionally, the improvement in thermal transport of viscoelastic fluid is suggested with radiative phenomenon. The convective boundary constraints are used to report the thermos-diffusion phenomenon. The system based on dimensionless form is obtained with interaction of new variables. The shooting technique is used for numerical observations by using MATLAB software. The physical impact of phenomenon in view of parameters is graphically attributed. It has been noted that increasing velocity profile is results due to curvature parameter and viscoelastic parameter. The enhancement in thermal profile is noted due to Dufour number and Eckert number. 相似文献
3.
《Journal of Saudi Chemical Society》2023,27(5):101708
Praseodymium oxide (Pr6O11), hematite (Fe2O3), graphene oxide (GO), and polycaprolactone (PCL) based polymeric nanocomposites (NCs) are fabricated, aiming their usage as bio-scaffold for medical purposes. Because of their distinctive light absorption and stability, Fe2O3 and Pr6O11 have been introduced as potential optical elements. The structure and size examination of NCs were executed by XRD, Raman, and FESEM. Pr6O11/Fe2O3/GO@PCL polymeric NC is exhibited Pr6O11, and Fe2O3 average size of 1.4, 0.4 µm, while average pores size 2.1 µm. As well, the Uv–Vis shows an absorption edge shifting along the x-axis that it begins with 3.1 eV for pure PCL, after that it declined to 1.7 eV for Pr6O11@PCL NC. Also, Pr6O11 @PCL, and Pr6O11/ Fe2O3@PCL NCs show the lowest similar contact angle with 38°. Regarding cell attachment evaluation test, the Pr6O11/Fe2O3/GO@PCL NC healing valuation is touched ∼ 80%. As a result, the structure enabled 3-dimensional the division of normal cells, so promoting wound healing. 相似文献
4.
Tibor Rozsa Mihaela Duma Laurian Vlase Ioana Ionuţ Adrian Pîrnău Brînduşa Tiperciuc Ovidiu Oniga 《Journal of heterocyclic chemistry》2015,52(4):999-1006
Thiazole and bisthiazole derivatives represent a prevalent scaffold in the antimicrobial drug discovery. Therefore, we have decided to synthesize some new series of 4,5′‐bisthiazoles. A total of 17 compounds were synthesized, their structural elucidation being based on elemental analysis (C,H,N,S) and spectroscopic data (MS and 1H NMR). Their in vitro antimicrobial activities were assessed against several Gram‐positive and Gram‐negative bacteria strains and also against one fungal strain (Candida albicans) using the difusimetric method. Some of the compounds showed modest to good antibacterial activity against Gram‐negative Escherichia coli and Salmonella typhimurium and Gram‐positive Staphylococcus aureus and Bacillus cereus bacterial strains. All of the synthesized compounds showed moderate to very good antifungal activity against C. albicans. 相似文献
5.
In recent years, the essential work of fracture (EWF) method has been extensively employed for assessing a material's toughness by specific essential fracture work, especially for polymers showing ductile failure. However, most research has studied either the in-plane stress mode or the out-of-plane stress mode. To obtain a more in-depth understanding of the EWF theory, the specific essential and non-essential fracture work of polypropylene random copolymer (PP-R) was investigated in both in-plane stress mode and out-of-plane stress mode. The effects of ligament length, amount of pre-cracking and pre-cracking method on the specific essential and non-essential fracture work were explored. The specific essential fracture work obtained in both stress modes is compared and discussed. 相似文献
6.
SiO2 nano particles, with particle size of 12 nm, were first modified by substituting surface OH groups with O-hexyl moiety. Then, poly1-hexene/modified-SiO2 composites with various nano-SiO2 weight fractions were prepared by three different methods: in situ, solution, and melt methods and designated as PH-SiO2/Insitu, PH-SiO2/Sol and PH-SiO2/Melt, respectively. PH-SiO2/Insitu samples showed highly uniform particle dispersion up to 30 wt. % of silica while in PH-SiO2/Sol and PH-SiO2/Melt samples agglomeration of the silica nanoparticles occurred for filler contents ≥5 wt. % (i.e. 5, 10, 20 and 30 wt%). In the synthesized composites, the storage modulus significantly increased as high as 20.7 times when compared with neat poly1-hexene. Maximum decomposition temperature (Tmax) and char yield at 600 °C increased with increasing silica level. Rheological results showed that Gʹ> Gʺ over the frequency range, illustrating the elastic behavior of the composite samples. In fact, samples showed the characteristic of a non-Newtonian fluid with a strong shear thinning effect in which η* increased with increasing filler weight fraction. From the results, it can be expected that modified silica could replace silica nanoparticles in polyolefin nanocomposite reinforcement. 相似文献
7.
Bio-based bacterial cellulose (BC) epoxy composites were manufactured and their mechanical properties were examined. The BC was initially fabricated from Vietnamese nata de coco by means of alkaline pretreatment followed by solvent exchange. The obtained fibers were dispersed in epoxy resin (EP) by both mechanical stirring and ultrasonic techniques. The resulting blend was used as the matrix for glass-fiber (GF) composite fabrication using a prepreg method followed by multiple hot-press-curing steps. The morphology, mechanical characteristics and mode-I interlaminar fracture toughness of the fabricated composites were investigated. With a 0.3-wt% BC content, the mode-I interlaminar fracture toughness for both crack initiation and crack propagation were improved by 128.8% and 1110%, respectively. The fatigue life was dramatically extended by a factor of 12, relative to the unmodified composite. Scanning electron microscopy images revealed that the BC plays a vital role in increasing the interlaminar fracture toughness of a GF/EP composite via the mechanisms of crack reflection, debonding and fiber-bridging. 相似文献
8.
Huu-Hung Nguyen Thi-Phuong Nguyen Nguyen Tien Trung Cam-Tu D. Phan Thi-Bich-Ngoc Dao Dinh-Tri Mai Jirapast Sichaem Ngoc-Hong Nguyen Cong-Luan Tran Thuc-Huy Duong 《Arabian Journal of Chemistry》2021,14(7):103189
Two new cycloartanes, combretanones G and H (1 and 2), were isolated from the leaves of Combretum quadrangulare. Their structures were elucidated by applying a set of spectroscopic methods, while their relative configurations were determined using DFT-NMR chemical shift calculations and subsequent assignment of DP4 probabilities. Compounds 1 and 2 are C-23/C-24 stereoisomers of the previously-reported euphonerin E. Both exhibited moderate cytotoxicity against three human cancer cell lines. Compound 2 was shown to be a potent antiparasitic. Our results confirm the traditional medicinal uses of Combretum quadrangulare in Vietnam. 相似文献
9.
Than Ha An Quoc Pham Thien Huu Nguyen Duyen Ky Vo Pham Thuong Hoai Khacef Ahmed 《Plasma Chemistry and Plasma Processing》2022,42(1):73-89
Plasma Chemistry and Plasma Processing - Non-thermal plasma is widely considered as an effective technology for applications in agriculture. Particularly, numerous reports studies have highlighted... 相似文献
10.
Liu Zhifang Zhang Shanyuan 《Acta Mechanica Solida Sinica》2006,19(1):1-8
A nonlinear wave equation of elastic rod taking account of finite deformation, transverse inertia and shearing strain is derived by means of the Hamilton principle in this paper. Nonlinear wave equation and truncated nonlinear wave equation are solved by the Jacobi elliptic sine function expansion and the third kind of Jacobi elliptic function expansion method. The exact periodic solutions of these nonlinear equations are obtained, including the shock wave solution and the solitary wave solution. The necessary condition of exact periodic solutions, shock solution and solitary solution existence is discussed. 相似文献