Effect of Template-Mediated Alumina Nanoparticle Morphology on Sapphire Wafer Production via Heat Exchange Method.

The sapphire crystal, the most commonly used LED substrate material, has excellent optical and chemical properties and has rapidly developed in recent years. However, the challenge of growing large-size sapphire crystals remains. This paper presents a novel approach using alumina nanoparticles synthesized with abietic acid as a template to enhance sapphire growth via the heat exchange method. This study explores the effects of temperature, time, and template amount on the structure and morphology of the synthesized alumina nanoparticles. The results show that the morphology of the raw material, particularly spherical alumina nanoparticles, positively affects the quality and yield stability of sapphire products. Furthermore, the light output power of GaN-based LED chips made with the experimentally fabricated sapphire substrate increased from 3.47 W/µm2 to 3.71 W/µm2, a 6.9% increase compared to commercially available sapphire substrates. This research highlights the potential of using abietic acid as a template for alumina nanoparticle synthesis and their application in sapphire growth for LED production.

The Morphologically Controlled Synthesis and Application of Mesoporous Alumina Spheres.

The control of alumina morphology is crucial yet challenging for its various applications. Unfortunately, traditional methods for preparing alumina particles suffer from several limitations such as irregular morphology, poor dispersibility, and restricted application areas. In this study, we develop a novel method for preparing spherical mesoporous alumina using chitin and Pluronic P123 as mixed templates. The effects of reaction temperature, time, and the addition of mixed templates on the phase structure, micromorphology, and optical absorption properties of the samples were investigated. The experimental results indicate that lower temperature and shorter reaction time facilitated the formation of spherical mesoporous alumina with excellent CO2 adsorption capacity. The periodic density functional theory (DFT) calculations demonstrate that both the (110) and (100) surfaces of γ-Al2O3 can strongly adsorb CO2. The difference in the amount of CO2 adsorbed by Al2O3 is mainly due to the different surface areas, which give different numbers of exposed active sites. This approach introduces a novel strategy for utilizing biological compounds to synthesize spherical alumina and greatly enhances mesoporous alumina's application efficiency in adsorption fields. Moreover, this study explored the electrochemical performance of the synthesized product using cyclic voltammetry, and improved loading of electrocatalysts and enhanced electrocatalytic activity were discovered.

Experimental and Simulation Research on the Preparation of Carbon Nano-Materials by Chemical Vapor Deposition.

Carbon nano-materials have been widely used in many fields due to their electron transport, mechanics, and gas adsorption properties. This paper introduces the structure and properties of carbon nano-materials the preparation of carbon nano-materials by chemical vapor deposition method (CVD)-which is one of the most common preparation methods-and reaction simulation. A major factor affecting the material structure is its preparation link. Different preparation methods or different conditions will have a great impact on the structure and properties of the material (mechanical properties, electrical properties, magnetism, etc.). The main influencing factors (precursor, substrate, and catalyst) of carbon nano-materials prepared by CVD are summarized. Through simulation, the reaction can be optimized and the growth mode of substances can be controlled. Currently, numerical simulations of the CVD process can be utilized in two ways: changing the CVD reactor structure and observing CVD chemical reactions. Therefore, the development and research status of computational fluid dynamics (CFD) for CVD are summarized, as is the potential of combining experimental studies and numerical simulations to achieve and optimize controllable carbon nano-materials growth.

Synthesis, Characterization and DNA Binding Investigations of a New Binuclear Ag(I) Complex and Evaluation of Its Anticancer Property.

AIM: A new Ag(I) complex (A3) was synthesized and evaluated for its anticancer activity against human cancer cell lines. MATERIALS AND METHODS: The complex A3 was characterized by 1H, 13C, and 31P nuclear magnetic resonance (NMR), infrared (IR) spectra, elemental analysis, and X-ray crystallography. The interaction of the complex with CT-DNA was studied by electronic absorption spectra, fluorescence spectroscopy, and cyclic voltammetry; cell viability (%) was assessed by absorbance measurement of the samples. RESULTS: The interaction mode of the complex A3 with DNA is electrostatic, and this complex shows good potential in anticancer properties against HCT 116 (human colorectal cancer cells) and MDA-MB-231 (MD Anderson-metastatic breast) cell lines with 0.5 micromolar concentrations. CONCLUSION: The Ag(I) complex could interact with DNA noncovalently and has anticancer properties.

[Effects of soybean isoflavones on the cell cycles, the cell apoptosis and the proliferation of spleen in radiated mice].

AIM: To study effect of soybean isoflavones (SI) on spleen in radiated mice. METHODS: 90 male mice were randomly divided into control group, radiated group, radiated plus 0.5% dose SI group. After 2-week feeding, the mice received 4.0 Gy 137Cs gamma-radiation, the cell cycles, cell apoptosis and proliferation on the spleen and the spleen index were observed in radiated after 12 h, 24 h, 1 week and 2 weeks. RESULTS: After the mice were radiated, the spleen were significantly atrophy, the rate of the cell apoptosis and the cell cycles of G0-G1 phase in splenocytes were significantly increased (P < 0.01), the cell cycles rate of S phase and the proliferation index were significantly decreased in spleen (P < 0.05). Compared with radiated group, the spleen atrophy and the rate of the cell cycles of G0-G1 phase were significantly decreased (P < 0.05), and the cell cycles of G2-M phase and the proliferation index were significantly increased (P < 0.05) in the mice supplied 0.5% soybean isoflavones. CONCLUSION: The soybean isoflavones could significantly increase spleen radioprotective effect in mice.

[The regulatory effects of arginine on hepatic insulin-like growth factor-1 secretion in rats and its implication].

OBJECTIVE: To explore the regulatory effect of arginine on the secretion of hepatic insulin-like growth factor-1 (IGF-I), and the mechanism of enhancing the immune function by arginine. METHODS: Wistar rats were randomly divided into normal control (NC), wound control (WC), and wound with arginine (Arg) groups, with 8 rats in each group. The rats in WC and Arg groups were inflicted with soft tissue trauma on the back. The rats in Arg group were fed a diet supplemented with 5% arginine for one week, while those in NC and WC groups were fed with glycine. The serum contents of arginine, ornithine, growth factor (GH), NO and IGF-I were determined 7 days after feeding. T cell proliferation and IGF-I mRNA expression in hepatic tissue were also measured. Meanwhile, the rat hepatocytes were cultured in serum-free medium containing different concentrations of arginine. The supernatant was collected for the determination of IGF-I level. RESULTS: 1). There was no obvious difference of the serum level of arginine and ornithine between NC and WC groups (P > 0.05), but the contents of them were obviously higher in the Arg group compared with other two groups (P < 0.01). 2). No difference in the serum GH level was found among all the groups (P > 0.05), but the serum NO content in WC and Arg groups was significantly lower than that in NC group (P < 0.01), and the serum IGF-I content in WC group decreased obviously compared with that in NC group (P < 0.01). 3). The thymocyte proliferation rate in WC group was also markedly lower than that in NC group (P < 0.01), but that in Arg group was improved compared with WC group (P < 0.01). 4). The expression of hepatic IGF-I mRNA: The relative value of IGF-I mRNA was 1.19 +/- 0.06, 1.08 +/- 0.06 and 1.29 +/- 0.06 in NC, WC and Arg, respectively, while the value in WC was lower than that in NC (P < 0.05) group, and that in Arg group was much higher than that in WC group (P < 0.01). 5). The IGF-I level in the supernatant of cultured hepatocytes: When Arg concentration was 0.0750, 0.7500, 7.5000 mmol/L in the culture medium, the IGF-I level in the supernatant of hepatic cell medi-um was obviously higher than that in the medium without arginine (P < 0.01). Although IGF-I level decreased in the culture medium with arginine in the dose of 37.5000 mmol/L, it was still obviously higher than that in the medium without arginine (P < 0.01). CONCLUSION: Arginine could also produce the immune enhancing effect by stimulating hepatic IGF-I secretion.

[Study on the effect of leptin on fibroblast proliferation and collagen synthesis in vitro in rats].

OBJECTIVE: To investigate the effect of leptin on fibroblast proliferation and collagen synthesis as to elucidate that fibroblasts play a role in leptin's effect on wound healing. METHODS: Purified dermal fibroblasts were derived from sucking wistar rat skin and exposed to leptin at concentration of 0, 10, 50, 100, 200, and 400 ng/ml. The survived fibroblasts were assessed by the colorimetric thiazolyl blue (MTT) assay. Replication of fibroblast was quantified by the incorporation of 3H-thymidine. Collagen synthesis of fibroblast cell was measured by the incorporation of 3H-proline into collagenase-sensitive protein. RESULTS: The absorption of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 0.082 +/- 0.013, 0.091 +/- 0.018 was higher than that of control group 0.063 +/- 0.010, P < 0.05. The incorporations of 3H-thymidine of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 379 +/- 101 cpm, 326 +/- 33 cpm were significantly higher than those of control group 219 +/- 56 cpm, P < 0.05. The incorporations of 3H-proline of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 911 +/- 55 cpm, 1 072 +/- 259 cpm were significantly higher than that of control group 679 +/- 176 cpm, P < 0.05. CONCLUSION: Leptin can promote rat cutaneous fibroblast proliferation and collagen synthesis in vitro. This suggests that cutaneous fibroblast plays a role in leptin's promoting skin wound healing and it may be one of the main mechanisms by which leptin enhances skin wound healing.

[Effects of genistein on bone mineralization in ovariectomized rats].

AIM: To investigate the effects of genistein on bone mineralization in ovariectomized rats. METHODS: Forty-seven Wistar rats were randomly allocated into six groups: sham-operated (sham), ovariectomized (ovx), ovariectomized supplied with diethyl stilbestrol (E, 20 microg x kg bw(-1) x d(-1)) or genistein (25, 50, 100 mg x kg bw(-1) x d(-1)). After the rats had been fed for three months, analysis of the bone mineral density, parameters related to mineralization, bone content of Ca, P, Mg, Mn and Zn and serum concentration of parathyroid calcitonin and estrogen was performed. RESULTS: Bone mineral density, bone Ca, P, Zn and Mg content and serum estrogen concentration in ovariectomized rats were significantly decreased, but mean osteoid width increased, mineralization lag time and osteoid maturation period prolonged compared with sham animals. After three months supplementation to ovariectomized rats, bone Ca, P and Mg content increased, mean osteoid width decreased, mineralization lag time and osteoid maturation period shortened compared with ovariectomized animals. CONCLUSION: Genistein promotes bone mineralization by increasing bone Ca, P, Mg and adjusting serum calcitonin to prevent osteoporosis.

[Effects of genistein on bone mineral density and biomechanical properties and morphometric parameters in ovariectomized rats].

OBJECTIVE: To investigate the effects of genistein on bone mineral density and biomechanical properties and morphometric parameters in ovariectomized rats. METHODS: Forty-seven Wistar rats were randomly allocated into six groups: sham-operated (sham), ovarietomized (ovx), ovarietomized supplied with diethyl stilbestrol (E, 20 microg/kg BW) or genistetin (25, 50, 100 mg/kg BW). After the rats had been fed for three months, the bone mineral density and biomechanical properties and histomorphometric parameters of the rats was analysed. RESULTS: The trabecular bone volume and the mean trabecular plate density and bone density of ovariectomized rats were significantly decreased, while the mean trabecular plate space increased compared with sham animals. After three months supplementation to ovariectomized rats, trabecular bone volume and mean trabecular plate density increased. CONCLUSION: Genistein can reduced bone loss on ovariecromized rats.

[Effects of genistein on proliferation and differentiation of osteoblast].

AIM: To study the effects of genistein on proliferation and differentiation of osteoblasts in neonatal rat calvaria cultures. METHODS: Osteoblasts were isolated from neonatal rat calvaria through trypsin and collagenase digestion, and cultured in the presence of different doses of genistein (10(-5) mol/L, 10(-6) mol/L and 10(-7) mol/L). The proliferation and DNA and collagen synthesis of osteoblasts were assayed by MTT method and 3H-TdR and 3H-proline incorporation. The activity of ALP were measured by ALP assay kit. RESULTS: Genistein significantly increased osteoblast 3H-TdR and 3H-proline incorporation and MTT, 10(-6) mol/L genistein increased ALP activity. CONCLUSION: Genistein increased osteoblast DNA and collagen synthesis in neonatal rat calvaria cultures, and promoted osteoblast proliferation and differentiation.