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21.
Wonghil Chang GeumHee Chae So Ra Jang Jihye Shin Byoung Joon Ahn 《Journal of Industrial and Engineering Chemistry》2012,18(2):581-585
Palladium catalysts, Pd/MCM-41 and Pd/SBA-15 were prepared by impregnation of an aqueous solution of [Pd(NH3)4]Cl2 on MCM-41 and SBA-15. Palladium contents of Pd/MCM-41 and Pd/SBA-15 are 8.4% and 8.7%, respectively. It has been shown that these catalysts are very suitable to microwave-assisted Suzuki reactions under solvent-free condition. It is also found that the base additives for this reaction are K2CO3, Cs2CO3 or CsF. Thus, phenylboronic acid and phenyl iodide with Pd/MCM-41 produce biphenyl by microwave irradiation for 10 min in 97.4% yield. Phenyl bromide, instead of phenyl iodide, also proceeds the reaction with phenylboronic acid using Pd/MCM-41 or Pd/SBA-15 yielding biphenyl by microwave irradiation for 10 min in excellent yield. Whereas the reaction of phenyl chloride with phenylboronic acid gives poor yield in same condition. Various aryl iodides and aryl bromides are tested. In this paper our recent results of microwave-assisted Suzuki reaction using Pd/MCM-41 and Pd/SBA-15 under solvent-free condition are described. 相似文献
22.
Effects of Color,Scouring Method,and Age on the Visual Sensibility of Naturally Colored Organic Cotton (NaCOC) 下载免费PDF全文
Jangwoon Park Yoon Chang Wongi Hong Myungeun Lee Ahreum Han Youngjoo Chae Gilsoo Cho Heecheon You 《人机工程学与制造业中的人性因素》2014,24(3):318-327
In parallel to the social trend of green consumerism and well‐being, the demand for naturally colored organic cotton (NaCOC) continually increases in the textile and clothing industry. The present study examined the effects of NaCOC color, scouring method, and age on the visual sensibility of NaCOC. Two age groups (20s and 30s; 40s and 50s) of women rated three color sets of NaCOC specimens (ivory, green, and coyote brown) treated by two chemical scouring methods (Na2CO3 and NaOH) and two bioscouring methods (enzyme and boiling water) using 7‐point scales of nine visual sensibilities (bright‐dark; clear‐murky; heavy‐light; vivid‐subdued; warm‐cool; fresh‐stale; strong‐weak; showy‐plain; and luxurious‐cheap). Preferred scouring methods by NaCOC color and/or age group were recommended for each visual sensibility (e.g., preferred scouring methods for fresh sensibility are Na2CO3 for ivory NaCOC, Na2CO3 and NaOH for green NaCOC, and boiling water for coyote brown NaCOC). In addition, the representative visual sensibilities of each NaCOC color (e.g., those of coyote brown NaCOC are dark, murky, heavy, vivid, warm, stale, strong, plain, and luxurious sensibilities) were identified for the women participants. Last, it was demonstrated that a bioscouring method can replace the traditional chemical methods for selected visual sensibilities (e.g., boiling water for luxurious sensibility). © 2012 Wiley Periodicals, Inc. 相似文献
23.
Template‐Directed Directionally Solidified 3D Mesostructured AgCl–KCl Eutectic Photonic Crystals 下载免费PDF全文
24.
Photonic Crystals: Template‐Directed Directionally Solidified 3D Mesostructured AgCl–KCl Eutectic Photonic Crystals (Adv. Mater. 31/2015) 下载免费PDF全文
25.
Prakash Parthasarathy Hang Seok Choi Hoon Chae Park Jae Gyu Hwang Ho Seong Yoo Byeong-Kyu Lee Mukesh Upadhyay 《Korean Journal of Chemical Engineering》2016,33(8):2268-2286
Waste tyres have become a grave concern as their accumulation is aggregating every year. Not only the size of waste tyre has to be reduced, but also some useful energy has to be recovered out of it as the world badly requires energy from alternate sources. Pyrolysis is one such method to extract energy potential products from waste tyres. It is extensively used to generate carbon black (solid product), tyre-oil (liquid product) and syngas (gas product) from waste tyres. In that connection, this article discusses the effect of various parameters on the product composition of pyrolysis of waste tyres. The current usage of pyrolysis products and their typical characteristics are also discussed in this critique. Of late, extraction of high value added products, such as activated carbon from carbon black, and limonene from tyre-oil is gaining attention. The article also throws some light on the application and generation routes of activated carbon and limonene from waste tyres. 相似文献
26.
Ji Eun Lee Hoon Chae Park Hang Seok Choi Seung Yeon Cho Tae Young Jeong Sung Cheoul Roh 《Korean Journal of Chemical Engineering》2016,33(3):782-794
Numerical simulations were conducted using computational fluid dynamics to evaluate the effect of ventilation conditions on radon (222Rn) reduction performance in a residential building. The results indicate that at the same ventilation rate, a mechanical ventilation system is more effective in reducing indoor radon than a natural ventilation system. For the same ventilation type, the indoor radon concentration decreases as the ventilation rate increases. When the air change per hour (ACH) was 1, the indoor radon concentration was maintained at less than 100 Bq/m3. However, when the ACH was lowered to 0.01, the average indoor radon concentration in several rooms exceeded 148 Bq/m3. The angle of the inflow air was found to affect the indoor air stream and consequently the distribution of the radon concentration. Even when the ACH was 1, the radon concentrations of some areas were higher than 100 Bq/m3 for inflow air angles of 5° and 175°. 相似文献
27.
Pamidimarri D.V.N. Sudheer Yokimiko David Cheol Gi Chae You Jin Kim Mary Grace Baylon Kei-Anne Baritugo Tae Wan Kim Min-Sik Kim Jeong Geol Na Si Jae Park 《Korean Journal of Chemical Engineering》2016,33(10):2788-2801
Coal, the most primitive fossil fuel, has been exploited for ages, and reserves dictate the economies of many countries. Presently, most energy is generated by direct combustion, raising concerns over global warming. Biological pretreatment of fossil resources and generation of alternative green energy can address the environmental issues associated with global coal utilization. Biological coal treatment can produce industrially important chemicals and bio-methane by employing microorganisms able to depolymerize/degrade coal. This review discusses current advances in microbial coal conversion, such as the efforts made to comprehend microbial processes, significant outputs of coal conversion, principle components responsible for coal conversion, and factors affecting the biological processes to convert coal. Development of these biological processes can be a stepping stone for greener coal; however, integration of multidisciplinary technologies is needed to increase the efficiency of economic coal utilization and production of economically and industrially feasible biomethane. 相似文献
28.
Sang-Ik Han Jong-Hyun Chae Kristin Bilyeu J. Grover Shannon Jeong-Dong Lee 《Journal of the American Oil Chemists' Society》2014,91(2):229-234
Soybean [Glycine max (L.) Merr] with increased oleic acid is desirable to improve oxidative stability and functionality of soybean seed oil. Recently, soybean genotypes with high oleic acid (≥70 %) were developed by breeding programs. Efficient and effective identification of high oleic acid soybean genotypes using non-destructive near infrared reflectance (NIR) on whole seeds would greatly enhance progress in breeding programs. The objective of this study was to develop a calibration equation for NIR determination of high oleic acid from single soybean seeds. A total of 600 intact, single F2 seeds were scanned by NIR. Spectral data were collected between 400 and 2,500 nm at 2 nm intervals. The relationship between NIR spectral patterns of each soybean seed and its oleic acid content was examined. The best predicted equations for oleic acid were selected on the basis of minimizing the standard error of cross-validation and increasing the coefficient of determination. Validation demonstrated that the equations for determining total oleic acid and over 50 % oleic acid content had high predictive ability (r 2 = 0.91 and r 2 = 0.99, respectively). To validate the newly developed equation, F2 seeds from a different genetic background were tested. Again, high oleic acid from single soybean seeds was accurately predicted from various genetic backgrounds. Therefore, applying the calibration equations to NIR will be useful to rapidly and efficiently select high oleic acid soybean genotypes in breeding programs. 相似文献
29.
HM, an HMG1-like mitochondrial DNA-binding protein, is required for maintenance of the yeast mitochondrial genome when cells are grown in glucose. To better understand the role of HM in mitochondria, we have isolated several multicopy suppressors of the temperature-sensitive defect associated with an abf2 null mutation (lacking HM protein). One of these suppressors, SHM1, has been characterized at the molecular level and is described herein. SHM1 encodes a protein (SHM1p) that shares sequence similarity to a family of mitochondrial carrier proteins. On glycerol medium, where mitochondrial function is required for growth, shm1 deletion mutants are able to grow, whereas shm1 abf2 double mutants are severely inhibited. These results suggest that SHM1p plays an accessory role to HM in the mitochondrion. The GenBank Accession Number for the SHM1 sequence is U08352. 相似文献
30.
Sun Woo Jin Gi Ho Lee Ji Yeon Kim Chae Yeon Kim Young Moo Choo Whajung Cho Eun Hee Han Yong Pil Hwang Yong An Kim Hye Gwang Jeong 《International journal of molecular sciences》2022,23(3)
Skeletal muscle is a heterogeneous tissue composed of a variety of functionally different fiber types. Slow-twitch type I muscle fibers are rich with mitochondria, and mitochondrial biogenesis promotes a shift towards more slow fibers. Leucine, a branched-chain amino acid (BCAA), regulates slow-twitch muscle fiber expression and mitochondrial function. The BCAA content is increased in porcine whole-blood protein hydrolysates (PWBPH) but the effect of PWBPH on muscle fiber type conversion is unknown. Supplementation with PWBPH (250 and 500 mg/kg for 5 weeks) increased time to exhaustion in the forced swimming test and the mass of the quadriceps femoris muscle but decreased the levels of blood markers of exercise-induced fatigue. PWBPH also promoted fast-twitch to slow-twitch muscle fiber conversion, elevated the levels of mitochondrial biogenesis markers (SIRT1, p-AMPK, PGC-1α, NRF1 and TFAM) and increased succinate dehydrogenase and malate dehydrogenase activities in ICR mice. Similarly, PWBPH induced markers of slow-twitch muscle fibers and mitochondrial biogenesis in C2C12 myotubes. Moreover, AMPK and SIRT1 inhibition blocked the PWBPH-induced muscle fiber type conversion in C2C12 myotubes. These results indicate that PWBPH enhances exercise performance by promoting slow-twitch muscle fiber expression and mitochondrial function via the AMPK/SIRT1 signaling pathway. 相似文献