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排序方式: 共有964条查询结果,搜索用时 15 毫秒
1.
Kannan K. Thirumalai Rameshbabu S. 《Journal of Mechanical Science and Technology》2018,32(4):1739-1747
Journal of Mechanical Science and Technology - This paper investigates the tribological characteristics of modified jojoba oil (MJO) as a base stoke for SAE20W40 mineral oil (LO). In addition, a... 相似文献
2.
Sundaram Vickram Karunakaran Rohini Subramanian Srinivasan David Nancy Veenakumari Kumar Archana Krishnan Anbarasu Palanivelu Jeyanthi Sundaram Thanigaivel Govindarajan Gulothungan Nanmaran Rajendiran Padmalayam Sadanandan Srikumar 《International journal of molecular sciences》2021,22(4)
Zinc (Zn), the second-most necessary trace element, is abundant in the human body. The human body lacks the capacity to store Zn; hence, the dietary intake of Zn is essential for various functions and metabolism. The uptake of Zn during its transport through the body is important for proper development of the three major accessory sex glands: the testis, epididymis, and prostate. It plays key roles in the initial stages of germ cell development and spermatogenesis, sperm cell development and maturation, ejaculation, liquefaction, the binding of spermatozoa and prostasomes, capacitation, and fertilization. The prostate releases more Zn into the seminal plasma during ejaculation, and it plays a significant role in sperm release and motility. During the maternal, labor, perinatal, and neonatal periods, the part of Zn is vital. The average dietary intake of Zn is in the range of 8–12 mg/day in developing countries during the maternal period. Globally, the dietary intake of Zn varies for pregnant and lactating mothers, but the average Zn intake is in the range of 9.6–11.2 mg/day. The absence of Zn and the consequences of this have been discussed using critical evidence. The events and functions of Zn related to successful fertilization have been summarized in detail. Briefly, our current review emphasizes the role of Zn at each stage of human reproduction, from the spermatogenesis process to childbirth. The role of Zn and its supplementation in in vitro fertilization (IVF) opens opportunities for future studies on reproductive biology. 相似文献
3.
Synthesis and characterization of poly(ethylene oxide)‐based glycopolymers and their biocompatibility with osteoblast cells 下载免费PDF全文
Mummuluri Trinadh Kannan Govindaraj Tota Rajasekhar Marshal Dhayal Annadanam V Sesha Sainath 《Polymer International》2015,64(6):795-803
Poly(ethylene oxide)‐block‐poly(methacryl‐d ‐glucopyranoside) (PEO‐GP) and poly(methacryl‐d ‐glucopyranoside) (H‐GP) glycopolymers were synthesized by deacetylation of acetylated polymers which were synthesized via atom transfer radical polymerization. The synthesized glycopolymers were characterized using 1H NMR, 13C NMR and Fourier transform infrared (FTIR) spectroscopies, gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The deacetylated polymers exhibited onset decomposition temperatures about 60 °C lower compared to the polymers having acetyl pendants. The glass transition temperature (Tg) of the acetylated homopolymer was 133 °C and that of the PEO‐based block copolymer was 124 °C. The deacetylated polymers H‐GP and PEO‐GP exhibited Tg values of about ?30 °C. Biocompatibility of the H‐GP and PEO‐GP glycopolymers was obtained by studying osteoblast cell adhesion, viability and proliferation in vitro. The cell viability showed an increase with increasing concentration of H‐GP from 0.1 to 1 µmol L?1 and then decreased with further increase in its concentration (10–1000 µmol L?1). PEO‐GP did not show a significant variation in cell viability on variation of its concentration from 0.1 to 1000 µmol L?1. The significant improvement in biocompatibility with osteoblast cells in the presence of PEO‐GP was considered as due to the covalently bonded PEO segment of the methacrylate glycopolymer block. © 2014 Society of Chemical Industry 相似文献
4.
Ponnusamy Nandha Kumar Shangavi Subramanian Uthirapathy Vijayalakshmi Sanjeevi Kannan 《Journal of the American Ceramic Society》2020,103(6):3528-3540
Structurally stable β-Ca3(PO4)2/t-ZrO2 composite mixtures with the aid of Dy3+ stabilizer were accomplished at 1500°C. The precursors comprising Ca2+, P5+, Zr4+, and Dy3+ have been varied to obtain five different combinations. The results revealed the fact that complete phase transformation of calcium-deficient apatite to β-Ca3(PO4)2 occurred only at 1300°C, whereas the evidence of t-ZrO2 crystallization is obvious at 900°C. The dual occupancy of Dy3+ at β-Ca3(PO4)2 and t-ZrO2 structures was evident; however, Dy3+ initially prefers to occupy β-Ca3(PO4)2 lattice until its saturation limit and thereafter accommodates at the lattice site of ZrO2. The typical absorption and emission behavior of Dy3+ were noticed in all the systems and, moreover, the surrounding symmetry of Dy3+ domains has been determined from the luminescence study. All the systems ensured paramagnetic response that is generally contributed by the presence of Dy3+. A gradual increment in the phase content of t-ZrO2 in the composite mixtures ensured a significant improvement in the hardness and Young's modulus of the investigated compositions. 相似文献
5.
Gui-Jia Gao Mei-Qi Zeng En-Liang Zhang Rong-Chang Zeng Lan-Yue Cui Dao-kui Xu Feng-Qin Wang M.Bobby Kannan 《材料科学技术学报》2021,83(24):161-178
The microstructure and chemical compositions of the solid solution-treated Mg-3Nd-1Li-0.2Zn alloy were characterized using optical microscope,scanning electron microscope(SEM),transmission electron microscope(TEM),electron probe micro-analyzer(EPMA)and X-ray photoelectron spectroscopy(XPS).The corrosion behaviour of the alloy was investigated via electrochemical polarization,electrochemical impedance spectroscopy(EIS),hydrogen evolution test and scanning Kelvin probe(SKP).The results showed that the microstructure of the as-extruded Mg-3Nd-1Li-0.2Zn alloy contained α-Mg matrix and nanometric second phase Mg41 Nd5.The grain size of the alloy increased significantly with the increase in the heat-treatment duration,whereas the volume fraction of the second phase decreased after the solid solution treatment.The surface film was composed of oxides(Nd2O3,MgO,Li2O and ZnO)and carbonates(MgCO3 and Li2CO3),in addition to Nd.The as-extruded alloy exhibited the best corrosion resistance after an initial soaking of 10 min,whereas the alloy with 4h-solution-treatment possessed the lowest corrosion rate after a longer immersion(1 h).This can be attributed to the formation of Nd-containing oxide film on the alloys and a dense corrosion product layer.The dealloying corrosion of the second phase was related to the anodic Mg41Nd5 with a more negative Volta potential relative to α-Mg phase.The preferential corrosion of Mg41Nd5 is proven by in-situ observation and SEM.The solid solution treatment of Mg-3Nd-1Li-0.2Zn alloy led to a shift in corrosion type from pitting corrosion to uniform corrosion under long-term exposure. 相似文献
6.
Joy Jestin Balakrishnan Kannan Madhavankutty Sreeraj 《Universal Access in the Information Society》2022,21(3):717-723
Universal Access in the Information Society - Lack of Sign Language-based learning tools is a hindrance in acquiring knowledge for deaf students. Technology-based tools have introduced innovative... 相似文献
7.
Kannan Govindan Devika Kannan K. Mathiyazhagan Ana Beatriz Lopes de Sousa Jabbour Charbel José Chiappetta Jabbour 《The International journal of environmental studies》2013,70(4):477-493
Industries need to adopt the environmental management concepts in the traditional supply chain management. The green supply chain management (GSCM) is an established concept to ensure environment-friendly activities in industry. This paper identifies the relationship of driving and dependence that exists between GSCM practices with regard to their adoption within Brazilian electrical/electronic industry with the help of interpretive structural modelling (ISM). From the results, we infer that cooperation with customers for eco-design practice is driving other practices, and this practice acts as a vital role among other practices. Commitment to GSCM from senior managers and cooperation with customers for cleaner production occupy the highest level. 相似文献
8.
To quantitatively characterize the substances contributing to estrogenic activity in river water, in vitro bioassay using MVLN cells and instrumental analysis using liquid chromatograph–mass spectrometer (LC/MS) or liquid chromatograph–tandem mass spectrometer (LC/MS/MS) were applied to river water extracts taken from various locations in the Tama River, Japan. Tama River water samples were extracted using solid phase extraction and the crude extracts were fractionated by high-performance liquid chromatography (HPLC) into 10 fractions. The sixth fraction contained nonylphenol (NP) and octylphenol (OP) at concentrations in the range of 51.6–147 and 6.9–81.9 ng/L, respectively (concentrations corresponding to the original sample volumes). No estrogenic activity, expressed as 17β-estradiol equivalents (E2-EQB), however, was observed in this fraction (<0.6 ng-E2eq/L). Instrumentally determined estrogenic activity (E2-EQC), which is the concentrations of NP and OP multiplied by their corresponding relative potency, was below the detection limit of the MVLN cell bioassay. Estrogenic activities were detected only in HPLC fraction nos. 7, 8 and 9. Estrone (E1), estradiol (E2) and bisphenol A (BPA) were detected in these fractions. Estriol (E3) and ethynylestradiol (EE2) were not detected (<0.2 ng/L) in these fractions. The calculated E2-EQC for BPA was below the detection limit of bioassay. The E2-EQC for E1 and E2 were on the same order as the estrogenic activity determined by the bioassay (E2-EQB). The ratios of E2-EQC and E2-EQB for E1 and E2 in the three factions collectively (nos. 7–9) were 0.49–0.97 and 0.29–1.12, respectively. Above results indicated that the major causal substances to the estrogenic activity in the Tama River were E1 and E2. 相似文献
9.
Jeya Jeevahan G. Mageshwaran G. Britto Joseph R. B. Durai Raj R. Thamarai Kannan 《Chemical Engineering Communications》2017,204(10):1202-1223
Energy demand, decreasing fossil fuel reserves, and health-related issues about pollutants have led researchers to search for renewable alternative fuels to either partially or fully replace fossil fuels. Among many alternative fuels, biodiesel became one of the most popular choices due to similar properties to that of conventional diesel. Biodiesel produces slightly lower brake thermal efficiency compared to that of conventional biodiesel, but has an advantage of reduced emissions of CO2, CO, HC, and smoke. However, biodiesel shows higher NOx emission which, when used in increased biodiesel market, may become a serious problem. Various strategies were attempted by different researcher to reduce NOx emissions. In this paper, various strategies, adapted for reducing NOx emissions of biodiesel fuel used in diesel engines for automobile applications, are reviewed and discussed. The strategies are grouped into three major groups, namely combustion treatments, exhaust after-treatments, and fuel treatments. Among various strategies discussed, fuel treatments, such as low temperature combustion, mixing fuel additives and reformulating fuel composition, reduce NOx emission without compromising other emission and performance characteristics and they seem to be promising for future biodiesel fuel. 相似文献