• Food Science and Biotechnology
• /
• v.15 no.3
• /
• pp.441-446
• /
• 2006

The biological effects of heating and chemical treatment on castor meal were investigated in order to develop a procedure to inactivate its antigenic activity in a way that is suitable for industrial applications. A 1% solution of purified castor bean allergen (CB-1A) was heat-treated with or without exposure to NaOH and NaOCI (250 ppm each). CB-1A exhibited extreme stability when heat-treated alone. In the presence of NaOH and NaOCl, CB-1A showed a drastic decrease in antigenic activity as the temperature surpassed the critical level of $70^{\circ}C$. The gradual disappearance of disc gel electrophoresis bands presumably responsible for the allergenicity of CB-1A, along with the significant losses of the amino acids phenylalanine, methionine, arginine, histidine, and cysteine correlated with the loss of CB-1A activity. CB-1A showed a single symmetrical band in SDS acrylamide gel electrophoresis with an estimated molecular weight of 6,000 daltons. The chemical and heat treatments reduced the disulfide bond content of CB-1A by 9.1% with a coincident increase in sulfhydryl bonds.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.15 no.2
• /
• pp.276-279
• /
• 2015

This paper presents two 3-stage D-band stacked amplifiers developed in a $0.13-{\mu}m$ SiGe BiCMOS technology, employed to compare the conventional cascode topology and the common-base (CB)/CB stacked topology. AMP1 employs two cascode stages followed by a CB/CB stacked stage, while AMP2 is composed of three CB/CB stacked stages. AMP1 showed a 17.1 dB peak gain at 143.8 GHz and a saturation output power of -4.2 dBm, while AMP2 showed a 20.4 dB peak gain at 150.6 GHz and a saturation output power of -1.3 dBm. The respective power dissipation was 42.9 mW and 59.4 mW for the two amplifiers. The results show that CB/CB stacked topology is favored over cascode topology in terms of gain near 140 GHz.

• Elastomers and Composites
• /
• v.22 no.3
• /
• pp.195-203
• /
• 1987

In this study, as one of the developing ways of the functional elastomer, improvement of the functionality of CB-BR was attempted through moisture curing reaction. The curing reaction of CB-BR was determined with an use of 3-aminopropyltriethoxysilane(APS) as a crosslinking agent, also a solution reaction with an active chlorine of CB-BR was elucidated by using a reaction kinetics theory and a study of physical property was made through moisture curing on the compound of 3-aminopropyltriethoxysilane and CB-BR The results of this study obtained are as follows : 1) CB-BR reacted easily with APS in the liquid state and the reaction rate coefficient and activation energy were as follows : 2) Optimum pressure condition of moisture cured elastomer(CB-BR+APS) was 20 minutes at $150^{\circ}C$, and the crosslinked elastomer was close to the theoretical value (q=1) for Flory's equation($\frac{\alpha}{\alpha-1}=q{\nu}RT$)

• Fibers and Polymers
• /
• v.1 no.1
• /
• pp.32-36
• /
• 2000

An alternative strategy to .educe the percolation threshold of carbon black (CB) in polymer blends was investigated using random copolymer ternary blends of polystyrene (PS), poly(methyl methacrylate)(PMMA), and a styrene-methyl methacrylate random copolymer (SMMA). The target morphology was to selectively locate CB particles in the encapsulating layer of SMMA during melt mixing. The CB used in this study is BP-2000 from Cabot and has a strong selective affinity to PS. Even when the CB was premixed with SMMA, it moves to the PS phase during the melt mixing. However, we also observed the CB particles located at the interface between SMMA and PS phases. Through this study it is found that the interaction between polymers and CB particles is critical for selectively localizing CB particles in multi-component polymer blends. Although appropriate processing condition may retard the movement of CB particles to the polymer phase with affinity, it cannot prevent it completely and locate them to the SMMA phase, which is not thermodynamically favored. To locate CB particles in an encapsulating layer of ternary polymer blends, first of all, polymers forming it should have selective affinity to CB.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.6
• /
• pp.1337-1340
• /
• 2009

Electrical properties of a fluorinated carbon black (CB)-filled high-density polyethylene (HDPE) polymeric switch were investigated as a function of fluorination pressure at 0.1 ~ 0.4 MPa. From the FT-IR results, the absorption spectra of the fluorinated CB show an absorption band at 1400 ~ 1000 $cm^{-1}\;for\;{\nu}_{C-F}$ and the peak intensity increased with increasing fluorination pressure. Also, the analysis of XPS spectra of the fluorinated CB indicated that fluorine content increased with increasing fluorination pressure. Meanwhile, the surface free energy of the fluorinated CB decreased with increasing fluorination pressure. Consequently, the increase of fluorine contents of CB made a disappearance of negative temperature coefficient (NTC) behavior of the polymeric switch, which was probably due to the reduction of CB reaggregation after melting point of the HDPE, resulted from the decreasing of London dispersive component of the surface free energy for CB particles.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.4
• /
• pp.514-521
• /
• 2022

We report the effect of pH on the supramolecular complexation of two biothiols, viz., homocysteine (Hcy) and cysteine (Cys), with cucurbit[7]uril (CB[7]). Under basic pH conditions, Cys did not complex with CB[7], whereas Hcy efficiently complexed with CB[7], as confirmed by ¹H NMR spectroscopy and Ellman's reagent (5,5'-dithio-bis(2-nitrobenzoic acid), DTNB) assay. ¹H NMR and Raman spectroscopic studies revealed that, in the absence of CB[7], Hcy auto-oxidized slowly (~36 h) to homocystine (HSSH) under basic pH conditions. However, the rate of Hcy oxidation increased by up to 150 fold in the presence of CB[7], as suggested by the DTNB assay. Thus, supramolecular complexation under basic pH conditions led to the formation of a HSSH-CB[7] complex, and not Hcy-CB[7]. The results indicate that Hcy is rapidly oxidized to HSSH under the catalysis of CB[7], which acts as a reaction chamber, in basic pH conditions. Our studies suggest that Hcy concentration, a risk factor for cardiovascular disease, can be selectively and more easily quantified by supramolecular complexation with CB [7].

• Journal of Service Research and Studies
• /
• v.10 no.4
• /
• pp.71-88
• /
• 2020

CB(Convertible bond) is mezzanine security that have the characteristics of bonds and stocks. From the perspective of investors, the purpose of the research is to empirically investigate the degree of investment efficiency of CB and to suggest efficient investment plans. The research method investigated the maturity interest rate, conversion price, and conversion date for CB, and then linked it with daily stock price fluctuations after the conversion date to determine the degree of investment efficiency and stock conversion effect of CB. As a result of the study, it was analyzed that the ratio of the conversion price exceeded days was only about 1/4 of the conversion date, so the investment efficiency was low. The conversion day yield was -6.3% on average and the maturity day yield was -5.2% on average, showing a minus return on average, which was calculated differently from investor expectations. It was analyzed that the number of stocks with a minus conversion day is 2.4 times greater than the number of plus stocks and 3.7 times more than the number of plus stocks with a minus maturity return, so the expected return on stock conversion of CB is low. The research contribution was derived from the problem that the expected rate of return of CB is not high, and it is that the investor's point of view when purchasing CB was established.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.4 no.2
• /
• pp.73-79
• /
• 2018

In our previous study, tricarbonyl $^{99m}Tc$-labeled TSPO-binding ligand, named $^{99m}Tc$-CB256, having positively charge (+1) was investigated but did not show promising results in in vivo environment despite of a nanomolar binding affinity for TSPO. Because the overall positively charge of $^{99m}Tc$-CB256 would likely interrupt its target protein uptake, we herein designed the neutral tricarbonyl-$^{99m}Tc$ labeled TSPO-binding ligand ($^{99m}Tc$-CB257, 1). $^{99m}Tc$-CB257 was prepared by the facile incorporation of the $[^{99m}Tc(CO)_3]^+$ into a N-(hydroxycarbonylmethyl)-2-picoly moiety in CB257. The radiochemical yield of $^{99m}Tc$-CB257 after HPLC purification was $54.1{\pm}2.4%$ (decay corrected, n = 3). The authentic Re-CB257 (2) was synthesized by using $(NEt_4)_2[Re(CO)_3Br_3]$ in 69.0% yield. The binding affinity of 2 for TSPO was measured in leukocyte and showed approximately 280 times higher than that observed for the positively charged (+1) ligand, Re-CB256 ($K_i=0.57{\pm}0.06nM$ versus $159.3{\pm}8.7nM$, respectively). Our results indicated that 1 can be considered potentially as a new SPECT radiotracer for TSPO-rich cancer and provides the foundation for further in vivo evaluation related with abnormal TSPO-overexpression environments.

• Journal of the Korean Applied Science and Technology
• /
• v.32 no.4
• /
• pp.718-723
• /
• 2015

For the fabrication of the Si negative electrode in Li-ion batteries (LIBs) containing the cross-linking polymer binder, in this work, the urethane acrylate (UA) oligomer was synthesized via a simple synthetic process. The cross-linked poly(urethane acrylate) (CPUA)/carbone black (CB)/Si composite (CPUA/CB/Si composite) was fabricated through reactions between their reactive vinyl segments in the UA oligomer. Interestingly, the CPUA/CB/Si composite showed better cycle performance than the poly(vinylidene fluoride) (PVdF)/CB/Si composite (PVdF/CB/Si composite) and the polyurethane (PU)/CB/Si composite (PU/CB/Si composite). The CPUA/CB/Si composite had the best lithiation of about $2586mAh\;g^{-1}$. The UA oligomer showed a good compatibility with the electrode materials and current collector after and before a curing process.

• Journal of Embryo Transfer
• /
• v.19 no.1
• /
• pp.35-42
• /
• 2004

The purpose of this study was to evaluate the effects of Cytochalasin B treatment on the survivability The different concentration and exposed times of CB of porcine embryos frozen by vitrification were observed. The results were summarized as follows ; 1. The survivability rates of the porcine embryos treated CB(60.5%) were significantly higher than non-treated(32.8%)(p＜0.1). However the recovered with normal morphology rates(84.2%) were no significantly different than non-treated(81.9%). 2. We observed by different concentration of CB treatment, the group of CB treated with 7.5 $\mu\textrm{g}$/$m\ell$ were significantly showed a higher of normal morphology(44/45; 98%) and viability rate(33/45;73%) than other groups(morphology: 65∼70%, viability: 15∼74%)(p<0.05). While the control was lower as 70% of morphology and 38% of viability. 3. We examined exposed time of in-vitro CB treated embryos, the group of more than 20 minutes exposed were significantly were observed a higher rates of normal morphology and viability(p<0.05). And the group of 13 minutes, 14,000 rpm centrifuged(64%) were significantly higher than non-centrifuged(36%). Survivability of porcine embryos were improved in CB treated group. It suggested that 7.5 $\mu\textrm{g}$/$m\ell$ concentration of CB treatment, 20 minutes exposed times and 13 minutes, 14000 rpm centrifuged prior to vitrification improve normal morphology and survivability rates.