A ‘‘micro-explosion” strategy for preparing membranes with high porosity, permeability, and dye/salt separation efficiency

Xinyang Li,Ligang Lin,Zitian Li,Jing Yang,Wensong Ma,Xu Yang,Xiaopeng Li,Chunhong Wang,Qingping Xin,Kongyin Zhao 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.119 No.-

In this study, inspired by ‘‘micro-explosion” strategies, a separation membrane with high porosity andpermeability, and highly efficient separation performance was prepared. With the use of polyvinylidenefluoride (Solvay6015) as membrane material, azodicarbonamide (AC) as an ‘‘explosion center point” tothe casting membrane solution, and NaOH as an ‘‘external stimulus” in the coagulation bath, the twochemicals undergo in-situ foaming reaction to form a loose nanofiltration membrane. FTIR, XPS, andTGA results demonstrated that the decomposition of AC was complete, which produced gases thatincreased the porosity of the membrane. The optimized membrane has a higher flux(101.72 L m2 h1 at 0.3 Mpa), higher negative surface charge, and better mechanical properties underthe premise of separating CR/NaCl. In the separation of pollutants with different molecular weights,the permeation flux of the optimized membrane increased by more than double. This foaming technologywas also applied to another membrane material, ethylene vinyl alcohol, from which we found that themembrane also had higher porosity and better permeability. Together, this paper presents an in-situfoaming method for preparing separation membranes and lays the foundation for solving the trade-offbetween membrane permeability and rejection in dye/salt separation.

The effect of aeration mode on the operational effectiveness and membrane bioreactors for greywater treatment and membrane fouling

Chunhong Shi,Bo Yan,Xiangmeng Zuo,Cheng Wang,Zifu Li,Lixin Zhu 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.2

This study aims to investigated the effect of aeration mode on membrane bioreactors (MBRs) using a self-designed integrated hollow fiber MBR and flat sheet organic MBR for rural greywater treatment. The pollutant removal efficiency, characteristics of activated sludge and mixed liquor, and mechanisms of membrane fouling were systematically analyzed under intermittent aeration and continuous modes. The results indicate that the permeability of MBRs in intermittent aeration mode is higher than that in the continuous aeration mode when operating at the same aeration rate. Due to the higher extracellular polymeric substance (EPS) and soluble microbial product (SMP) concentrations. The removal rates of TN and TP by both MBRs at the intermittent aeration mode were higher than those in the continuous aeration mode due to the difference in the aeration environment. Compared to the flat-sheet organic membrane, the hollow-fiber membrane surface was more likely to form biofilms, which cause biological fouling.The relative abundance of Thermomonas showed a positive correlation with the EPS concentration, indicating that Thermomonas participates in EPS synthesis. This study provides a theoretical basis for evaluating the influence of aeration modes on MBRs,and would be a useful guide for the better control of membrane fouling and treatment of rural greywater.

Influence of Hemp Fiber Softening Treatment & Blend Ratio on Quality Characteristics of Hemp-Based Ternary Blended YARNS

Chuanhe Li,Ruiqi Shao,Chunhong Wang,Guangwei Fu,Bingjie Yang 한국섬유공학회 2023 Fibers and polymers Vol.24 No.10

Quality characteristics of blended yarns, which play an important role in textile quality, are continually assessed by softness, breaking strength, breaking elongation, hairiness, irregularity, etc. In this study, hemp was softened and blended with other cellulose fibers with better softness to produce yarns. The softness of hemp is obviously lower than that of the other two fibers. With the increase of hemp fiber percentage content, the yarn properties deteriorated. Therefore, the softening treatment of hemp fiber is very necessary. Moreover, the blending hemp, cotton, and viscose in the yarn structure provided synergies, improving the weak properties of ternary fibers. Results show that softening treatment and lower percentage content of the hemp fiber will result in better yarn quality, which is consistent with the derivation result of the bending theoretical model. When the percentage content of treated hemp is 40 wt%, the overall performance of blended yarn is the best. Compared with the untreated hemp-based ternary blended yarns, the hairiness of blended yarn is significantly less (3.65 ends/m, compared to 12.23 ends/m), and the irregularity of yarn is lower (27.33% and 27.70%, respectively), yarn quality improved considerably. In addition, the resulting hemp yarn showed antibacterial activity against Escherichia coli and Staphylococcus aureus.

Design of Novel Reactive Dyes Containing Cationic Groups: Mechanism and Application for Environmentally Friendly Cotton Dyeing

Meihui Wang,Chong Guo,Chunhong Li,Tao Zhao 한국섬유공학회 2020 Fibers and polymers Vol.21 No.12

In this work, four novel, high fixation reactive dyes containing cationic groups were synthesized using maminophenyltrimethylammoniumsalt or 4-(ethylsulfurate sulfonyl) aniline as the diazo component, 3-(N,N-diethylamino)acetanilide or 3’-aminoacetanilide as the coupling component and m-aminophenyltrimethylammonium salt or N-(2-aminoethyl)pyridinium chloride as the cationic group. The synthesized dyes containing multiple cationic groups were characterized by FTIRand 1H-NMR spectroscopy. The spectral properties were measured by UV-Vis absorption spectroscopy. Compared withconventional reactive dyes containing cationic groups, the synthesized dyes exhibited good water solubility uponintroduction of a quaternary ammonium into the chromophore. The structural design of synthetic azo dyes allows enhancedthe water solubility due to the introduction of a cationic group. The dyeing properties of the synthesized dyes to cotton fabricwere explored at various temperatures and salt and alkaline concentrations. The results showed that the synthesized dyespossessed good dyeing properties with nearly 80% fixation and good color fastness on cotton (3-5) in the absence of salt. Thesuccess of the salt-free dyeing of cotton fabric with these dyes is an excellent example of environmentally friendly cottondyeing. This study provides an important platform for the design of novel reactive dyes for cotton dyeing to reduce effluentpollution.

A personalized prognostic model for long-term survival in patients with intrahepatic cholangiocarcinoma: a retrospective cohort study

Xianhui Dong*,Pengwei Zhang*,Chunhong Ye,Li Li 대한외과학회 2024 Annals of Surgical Treatment and Research(ASRT) Vol.107 No.1

Purpose: This study aimed to determine the optimal cutoff points for age and tumor size of patients with intrahepatic cholangiocarcinoma (ICC) and to establish and verify a predictive nomogram of overall survival at 1, 3, and 5 years. Methods: From the SEER (Surveillance, Epidemiology, and End Results) database, 1,325 ICC patients were selected and randomly divided into training and testing cohorts at a 7:3 ratio. Using the X-tile software, age and tumor size were classified into 3 subgroups: ≤61, 62–74, and ≥75 years and ≤35, 36–55, and ≥56 mm. Subsequently, univariate and multivariate Cox regression analyses were performed using the R software in the training cohort to determine independent risk factors, compile the prediction nomogram, and verify it with the testing cohort findings. Results: The C-indexes of the new prediction nomograms in the training and testing cohorts were 0.738 (95% confidence interval [CI], 0.718–0.758) and 0.750 (95% CI, 0.72–0.78), respectively. Furthermore, the areas under the 1-, 3-, and 5-year receiver operating characteristic (ROC) curves based on the nomogram were 0.792, 0.853, and 0.838, respectively, higher than the ROC based on the 7th and 8th editions of the American Joint Cancer Commission (AJCC) staging system. Conclusion: This study established and verified a prognostic nomogram that improved the accuracy of the 1-, 3-, and 5-year survival predictions for ICC patients, compared with that based on the 7th and 8th editions of the AJCC staging system, and can help clinicians make personalized survival predictions.

Efficient Removal of the Organochlorine Pesticide and Heavy-Metal Residues in Epimedium brevicornum Maxim by Supercritical Fluid Extraction

Zhao, Chunjie,Bai, Lu,Li, Huanxin,Li, Fei,Xin, Chunhong 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.12

A method involving depuration of 12 organochlorine pesticides (OCPs) and 7 heavy metals from Epimedium brevicornum Maxim was developed using supercritical fluid extraction (SPE). The pesticides in the study consisted of ${\alpha},\;{\beta}-,\;{\gamma}-,\;and\;{\delta}-Benzene$ hexachloride, Pentachloronitrobenzene (PCNB), Pentachloroaniline (PCA), Heptachlor (HEPT), Methyl -pentachlorophenyl sulfide (MPCPS), pp'-DDE[1,1-dichloro-2, 2-bis (p-chlorophenyl) ethylene], op'-DDT [1,1,1-trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane], pp'-DDD [1,1-dichloro-2-2-bis(p-chlorophenyl)]ethane, pp'-DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane]. A series of experiments was conducted to optimize the final extraction conditions as following: pure $CO_2$, extraction pressure of 15 Mpa, extration temperature of $60^{\circ}C$, extraction time of 10 min, flow rate at 55 kg/h. A GC method with electron capture detection was employed to determination of the OCPs, and an atomic absorption spectrometry (AAS) was designed for the determination of 7 heavy metals including of Pb, Cd, Cu, Fe, Zn, As, Hg in Epimedium brevicornum Maxim. A HPLC method was developed for the quantitative determination of active constituents. The SFE was used to remove the organochlorine pesticide and heavy metals from Epimedium brevicornum Maxim, receiving high decontamination rate of pesticide residue and low loss of active constituents.

Modelling and Prediction of Stress Relaxation for Thermal Bonded Nonwoven Geotextiles

Shiyuan Sun,Xiaoping Gao,Chunhong Fu,Yudong Zhou,Xiaoying Wei,Jiaxin Li,Yiping Qiu 한국섬유공학회 2020 Fibers and polymers Vol.21 No.7

Stress relaxation experiments were performed on three types of thermal bonded nonwoven geotextiles in this studyto model and predict their stress relaxation behaviors. Four mechanical models, including the standard linear solid mechanicsmodel, Eyring’s model, the modified two-Maxwell-unit model and the modified three-Maxwell-unit model were used topredict stress values for 600 h based on 3 and 90 h experimental relaxation data. Results indicated that Eyring’s model and themodified three-Maxwell-unit model fitted the experimental results better than the other two. Estimation using modified three-Maxwell-unit model seemed to construct an upper bound while that using Eyring’s model form a lower bound for thecorresponding experimental data. In addition, predicted curves were much closer to the experimental curve when equationsof the two models were built with the 90 h experimental data than those data of 3 h. Thus, the prediction capability of the twomodels can be substantially improved by employing the data with longer time. In summary, the combination of the modifiedthree-Maxwell-unit model and Eyring’s model can well forcast the range of actual stress during stress relaxation experimentswith the longer term experimental data.

Effect of curing mechanism on sulfuric acid corrosion resistance of geopolymer recycled aggregate concrete

Zhenmeng Chen,Hui Liu,Pinghua Zhu,Haichao Li,Tianze Ge,Lei Yang,Chunhong Chen,Yanlong Dong 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.4

To explore the effect of curing mechanism on the mechanical properties and sulfuric acid corrosion resistance of the geopolymer recycled aggregate concrete (GRAC), the specimens were cured at high temperature (60oC, 80oC) for 6 h, 24 h and 48 h respectively, and then lasted up to 7 d at room temperature. After the curing period was over, the laboratory accelerated simulation test of specimens was carried out by the periodic immersion method: the GRAC specimens (φ 50 × 100 mm) were immersed in the sulfuric acid solution with pH = 1 for 5 d and then dried at room temperature for 24 h, with a total circulation of 90 d. The results showed that after being eroded by sulfuric acid solution, the GRAC specimens cured at 60oC for 48 h had higher compressive strength with 19.9 MPa, lower mass loss rate (only 0.23%) and neutralization depth (5.71 mm) than those under other curing time. The GRAC specimens cured 80oC for 24 h also had a good performance: compressive strength achieved 16.9 MPa and had lower neutralization depth (5.99 mm), which was less affected by sulfuric acid corrosion. However, the GRAC specimens cured at 60oC for 48 h had the better mechanical properties than that cured at 80oC for 24 h. Excessive high temperature curing (80oC) would lead to more voids and microcracks inside GRAC, and destroy the dense structure, thereby reducing mechanical property of concrete. These voids and pores provided more erosion channels for sulfuric acid solution, which accelerated the corrosion rate. From the point of view of energy saving and concrete performance, no more than 60°C of curing temperature is recommended for industrial use.

Efficient Removal of the Organochlorine Pesticide and Heavy-Metal Residues in Epimedium brevicornum Maxim by Supercritical Fluid Extraction

Chunjie Zhao,Lu Bai,Huanxin Li,Fei Li,Chunhong Xin 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.12

A method involving depuration of 12 organochlorine pesticides (OCPs) and 7 heavy metals from Epimedium brevicornum Maxim was developed using supercritical fluid extraction (SPE). The pesticides in the study consisted of α, β-, γ-, and δ-Benzene hexachloride, Pentachloronitrobenzene (PCNB ), Pentachloroaniline (PCA), Heptachlor (HEPT), Methyl -pentachlorophenyl sulfide (MPCPS), pp'-DDE[1,1-dichloro-2, 2-bis (p-chlorophenyl) ethylene], op'-DDT [1,1,1- trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane], pp'-DDD [1,1-dichloro-2-2-bis(p-chlorophenyl)] ethane, pp'-DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane]. A series of experiments was conducted to optimize the final extraction conditions as following: pure CO2, extraction pressure of 15 Mpa, extration temperature of 60oC, extraction time of 10 min, flow rate at 55 kg/h. A GC method with electron capture detection was employed to determination of the OCPs, and an atomic absorption spectrometry (AAS) was designed for the determination of 7 heavy metals including of Pb, Cd, Cu, Fe, Zn, As, Hg in Epimedium brevicornum Maxim. A HPLC method was developed for the quantitative determination of active constituents. The SFE was used to remove the organochlorine pesticide and heavy metals from Epimedium brevicornum Maxim, receiving high decontamination rate of pesticide residue and low loss of active constituents.

A Decision-Making Method for Selecting Cloud Computing Service based on Information Entropy

Rong Jiang,Hongzhi Liao,Ming Yang,Chunhong Li 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.4

This paper proposes an information-entropy-based decision-making method for selecting cloud computing service. Firstly, an evaluation index system (EIS-DMSCS) is developed. Secondly, a decision-making method is constructed. Finally, the application example proves the scientificity, effectiveness and feasibility of this method.