Toughening of melamine–formaldehyde foams and advanced applications based on functional design

Bing Song,Xueli Zhu,Wei Wang,Liang Wang,Xiaoyuan Pei,Xiaoming Qian,Liangsen Liu,Zhiwei Xu 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.119 No.-

Owing to the intrinsic flame-retardancy, thermal stability, sound absorption, and easy processing, melamine–formaldehyde foams(MFs) have drawn substantial attention. Typically, the high-porosity and compressibilityof flexible MFs render them suitable for the construction of 3D templates and in thefabrication of porous N-doped carbon materials. But the widespread applications of MFs still suffer highbrittleness and low strength, calling for modifying and toughening MFs with more facile and economicalmethods, and much potential in advanced applications by functional design deserves further exploration. This review comprehensively summarized and evaluated the recent progress of the toughening methodsof MFs. We will also look into the applications of commercial MFs, carbonized MFs and foam-based compositesin flame retardancy and thermal management, oil/water separation, photothermal conversion,electrical energy storage, and other fields, aiming to give a guide for the preparation, modification, andexploitation of MFs both in traditional and emerging areas.

Fe0/C-bentonite alginate beads and oyster shell fixed-bed column combined process to continuously remove N-acetyl-p-aminophenol in persulfate system

Bing-huang Wang,Qian Zhang,Jun-Ming Hong 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.67 No.-

In this study, the ion-gelation method was applied to fabricate novel Fe–carbon–bentonite–alginate beads (Fe0/C-BABs). Fe0/C-BABs could effectively control Fe release during persulfate (PS) activation in N-acetyl-p-aminophenol (APAP) oxidation. A novel two-stage approach that combined Fe0/C-BABs and an oyster-shell-filled bed (OSFB) column was developed to address the low pH and high Fe concentration of the effluent of the traditional PS process. The application of the Fe0/C-BABs and OSFB column regulated pH levels and Fe release during the advanced oxidation of APAP. The characteristics of Fe0/C-BABs were also investigated through scanning electron microscopy, energy dispersive spectrometry, and Fourier transform infrared spectroscopy. The long-term operation performance of Fe0/C-BABs in a continuous fixed-bed reactor under simultaneous PS and APAP feeding was also evaluated. The effects of initial PS concentration, pH, fixed-bed weight, in-flow rate, and dissolved oxygen (DO) were investigated. Under selected conditions, 86.3% efficiency was achieved during the first stage of APAP degradation (effluent pH of 3.05, Fe contents: 106.25 mg L−1). Water quality improved after the effluent was passed through the OSFB column (effluent pH of 6.32, Fe contents: 21.43 mg L−1). Moreover, this study analyzed the free radicals and intermediates produced during APAP degradation to identify the possible routes of APAP degradation.

Influence of nickel-zinc ratio on microstructure, magnetic and dielectric properties of Ni(1−x)ZnxFe2O4 ferrites

Qian Liu,Li Lv,Jian-Ping Zhou,Xiao-Ming Chen,Xiao-Bing Bian,Peng Liu 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.2

Ni(1−x)ZnxFe2O4 (x = 0 − 1.0) ceramics were synthesized by a conventional solid-state reaction method. The samples have been investigated for their structures, microstructures, dielectric and magnetic properties in detail. A pure spinel crystal structure was obtained in the sintering temperature range of 1150-1250oC. The dielectric properties of part samples present a Debye relaxation phenomenon. The Curie temperature reduces linearly with the zinc concentrations. The magnetic permeability and saturation magnetization increase firstly to high values and then reduce with the zinc concentration. But the coercivity shows a different behavior. It increases at first and then decreases for the samples sintered at 1200oC while it descends monotonically with the zinc concentration for the samples sintered at 1250oC.

Effect of Collagen Scaffold with Adipose-derived Stromal Vascular Fraction Cells on Diabetic Wound Healing: A Study in a Diabetic Porcine Model

Yanan Jiang,Bing Chen,Yongbo Liu,Zhongyin Zhufu,Xin Yan,Xianglin Hou,Jianwu Dai,Qian Tan 한국조직공학과 재생의학회 2013 조직공학과 재생의학 Vol.10 No.4

Diabetes can impair neovascularization important for wound healing, and this study investigated the hypothesis that this effect can be reversed by an active provisional matrix. Here, a 3D collagen scaffold and uncultured adipose-derived SVFs were firstly utilized to construct a collagen-targeting system for wound healing in a diabetic porcine model. The diabetic porcine models were made by injected streptozocin (STZ) intravenously and removed full thickness skin from the dorsum. Each animal received four different samples: Group A (control groups, n=24), Group B (SVFs groups, n=24), Group C (scaffold groups, n=24), Group D (SVFs -scaffold groups, n=24). PBS was applied to the wounds in Group A. 1×105 SVFs suspended in PBS were sprayed on the wounds in Group B. Scaffolds only with PBS were covered on the wounds in Group C. Scaffolds with equal volume of cell suspension containing 1×105 SVFs were covered on the wounds in Group D. The healing rates were calculated and compared among the groups and the tissues of the wound were taken and evaluated for histological analysis. The diabetic wound treated with the SVFs -collagen scaffold showed a significant decrease in wound size, an increase of neovascularization and a maximum VEGF and bFGF expression in comparison with SVFs and scaffold alone. The SVFs-collagen scaffold accelerates wound healing since it stimulates higher capillary formation causes major proangiogenesis factors expression in diabetic pigs suffering from skin defects, suggesting this approach could have utility for diabetic wound healing.

Carbohydrate metabolism genes dominant in a subtropical marine mangrove ecosystem revealed by metagenomics analysis

Huaxian Zhao,Bing Yan,Shuming Mo,Shiqing Nie,Quanwen Li,Qian Ou,Bo Wu,Gonglingxia Jiang,Jinli Tang,Nan Li,Chengjian Jiang 한국미생물학회 2019 The journal of microbiology Vol.57 No.7

Mangrove sediment microorganisms play a vital role in the energy transformation and element cycling in marine wetland ecosystems. Using metagenomics analysis strategy, we compared the taxonomic structure and gene profile of the mangrove and non-mangrove sediment samples at the subtropical estuary in Beibu Gulf, South China Sea. Proteobacteria, Bacteroidetes, and Firmicutes were the most abundant bacterial phyla. Archaeal family Methanosarcinaceae and bacterial genera Vibrio and Dehalococcoides were significantly higher in the mangrove sediments than in the nonmangrove sediments. Functional analysis showed that “Carbohydrate metabolism” was the most abundant metabolic category. The feature of carbohydrate-active enzymes (CZs) was analyzed using the Carbohydrate-Active EnZymes Database. The significant differences of CZs between mangrove and non-mangrove sediments, were attributed to the amounts of polyphenol oxidase (EC 1.10.3.-), hexosyltransferase (EC 2.4.1.-), and β-N-acetylhexosaminidase (EC 3.2.1.52), which were higher in the mangrove sediment samples. Principal component analysis indicated that the microbial community and gene profile between mangrove and non-mangrove sediments were distinct. Redundancy analysis showed that total organic carbon is a significant factor that affects the microbial community and gene distribution. The results indicated that the mangrove ecosystem with massive amounts of organic carbon may promote the richness of carbohydrate metabolism genes and enhance the degradation and utilization of carbohydrates in the mangrove sediments.

Utilization of Potato Starch Processing Wastes to Produce Animal Feed with High Lysine Content

( Ying Li ),( Bing Nan Liu ),( Jin Zhu Song ),( Cheng Jiang ),( Qian Yang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.2

This work aims to utilize wastes from the potato starch industry to produce single-cell protein (SCP) with high lysine content as animal feed. In this work, S-(2-aminoethyl)-L-cysteine hydrochloride-resistant Bacillus pumilus E1 was used to produce SCP with high lysine content, whereas Aspergillus niger was used to degrade cellulose biomass and Candida utilis was used to improve the smell and palatability of the feed. An orthogonal design was used to optimize the process of fermentation for maximal lysine content. The optimum fermentation conditions were as follows: temperature of 40°C, substrate concentration of 3%, and natural pH of about 7.0. For unsterilized potato starch wastes, the microbial communities in the fermentation process were determined by terminal restriction fragment length polymorphism analysis of bacterial 16S rRNA genes. Results showed that the dominant population was Bacillus sp. The protein quality as well as the amino acid profile of the final product was found to be significantly higher compared with the untreated waste product at day 0. Additionally, acute toxicity test showed that the SCP product was non-toxic, indicating that it can be used for commercial processing.

제7회 한증 형법 국제 학술심포지움 : 중국 환경범죄의 형법입법 완선에 관한 연구

쉬이첸페이 ( Xu Qian Fei ),짜오삥쯔 ( Zhao Bing Zhi ) 한국비교형사법학회 2009 비교형사법연구 Vol.11 No.2

최근 중국 환경범죄의 형법입법은 입법체제, 죄명체계, 범죄구성, 형벌처벌 등 면에서 모두 문제들을 갖고 있어 보완할 필요가 있다. 이를 위하여 과학적인 환경범죄 형법 입법 체제, 환경범죄의 죄명체계와 범죄구성의 완선(完善), 환경범죄의 형벌적용원칙의 완선, 형벌종류, 환경범죄의 형벌강도 조정을 확립해야 한다. 환경범죄 형법입법 완선을 진행할 때 반드시 형법의 보충성을 고수하여 환경 윤리관념의 갱신을 진행해야 한다.

The joint effect of different concentration of Cd<SUP>2+</SUP> and ionic liquid on the growth of wheat seedlings

Zhonglin Chen,Qian Zhou,Feng Leng,Bing Dai,Xueyang Zhao,Weichen Zhang,Neng Liu,Wei Guan,Kui Liu 대한환경공학회 2017 Environmental Engineering Research Vol.22 No.3

The joint effect of different concentrations (0.05-0.375 mmol/L) of Cd<SUP>2+</SUP> and various concentrations (50-400 mg/L) of [C3mim][OAc] on the growth and physiology of wheat seedlings were investigated. The toxicity of Cd<SUP>2+</SUP> could be significantly reduced by lower concentrations (50-200 mg/L) of [C3mim][OAc]. With higher concentration (≥ 300 mg/L) of [C3mim][OAc], the reduction became less, and compared to Cd<SUP>2+</SUP> stress only, the toxicity of 400 mg/L [C3mim][OAc] increased. As for different Cd<SUP>2+</SUP> concentrations, the optimal reduction depends on the balance between the exact concentration of Cd<SUP>2+</SUP> and [C3mim][OAc]: With low Cd<SUP>2+</SUP> concentration (0.05-0.250 mmol/L) requiring 50 mg/L [C3mim][OAc], it could reach a dynamic equilibrium, while high Cd<SUP>2+</SUP> concentration (0.375 mmol/L) requiring 100 mg/L [C3mim][OAc]. The growth and physiological indexes of wheat seedlings show a decrease in toxicity compared to the Cd alone treatment, when the dynamic equilibrium is reached. The concentration of Cd<SUP>2+</SUP> in leaf tissues showed that low concentration (50-200 mg/L) of [C3mim][OAc] can reduce the toxicity of Cd<SUP>2+</SUP> (0.05-0.375 mmol/L) by decreasing the level of Cd<SUP>2+</SUP> concentration in the tissues, whereas the higher concentration (≥ 300 mg/L) of [C3mim][OAc] can increase the concentration of Cd<SUP>2+</SUP>.

제7회 한증 형법 국제 학술심포지움 : 납치죄 논쟁문제 연구

짜오삥쯔 ( Zhao Bing Zhi ),치옌샤오핑 ( Qian Xiao Ping ) 한국비교형사법학회 2009 비교형사법연구 Vol.11 No.2

납치죄는 인권을 침해하는 비교적 복잡하고 심각한 범죄이며 형법이론과 사법실무 중에 일련의 문제를 가지고 있다. 본문은 납치죄의 형사책임연령 문제를 해결하기 위해서는 <형법개정안(7)>에서의 납치죄에 관한 부분을 종합하여 형법 제17조제2항 납치죄의 죄명규정을 추가해야할 필요성을 주장한다. 납치죄의 주관적 측면에서는 합리적으로 범죄목적을 해석해야한다. 납치죄의 미수와 중지형태의 인정측면에서는 ``단일행위설``을 유지해야한다. 납치죄의 가중측면에서는 ``피납치자의 살해``를 결과가중범으로 이해해야 하며, 납치죄의 감경문제에서는 ``비교적 경한 정황``의 성격과 범위를 주의해야한다. 이러한 것을 기초로 본문은 납치죄의 입법보완에 대한 건의를 제시하고자 하였다.

Polyethylene Terephthalate/Carbon Fabric/Polyurethane Foam Sandwich Composites: Flame Retardance and Mechanical Properties

Liwei Wu,Jingyan Ban,Qian Jiang,Ting-Ting Li,Bing-Chiuan Shiu,Shih-Yu Huang,Ching-Wen Lou,Jia-Horng Lin 한국섬유공학회 2019 Fibers and polymers Vol.20 No.6

Polyethylene terephthalate (PET) nonwoven fabrics, carbon fabrics (CF), and flexible polyurethane (PU) foamsare made into novel sandwich composites using one-step molding. The flame retradance and mechanical properties of thesandwich composites are evaluated, examining the influences of the content of flame retardant agent (20, 30, 40, and 50 wt%)and areal density of PET panels (200, 300, and 400 g/m2). The test results show that the PET/CF/PU sandwich composites arerated flame retardant as V0 and do not generate melts. The failure mode of PET/CF/PU sandwich composites converts fromoverall fracture to layered fracture as a result of increasing the flame retardant agent. The tensile strength at break of PET/CF/PU sandwich composites with corresponding PET panels is 650 N for 200 g/m2, 928 N for 300 g/m2, and 1744 N for 400 g/m2,which are 42.63 %, 60.48 %, and 77.85 % greater than those of the PET/PU sandwich composites. Moreover, the burstingstrength of PET/CF/PU sandwich composites with corresponding PET panels is 3322 N for 200 g/m2, 3869 N for 300 g/m2,and 4978 N for 400 g/m2, which are 195 %, 180 %, and 143 % greater than those of the PET/PU sandwich composites.