Refining Characteristics of Hardwood Pulp Using Straight- and Curved-bar Plates: A Time Series Study

Huan Liu,Jixian Dong,Xiaojun Jiang,Chong Luo,Xiaohui Tian,Ruifang Yang,Litao Zhang,Bo Wang,Yan Yan 한국펄프·종이공학회 2019 펄프.종이기술 Vol.51 No.5

There are obvious differences in the refining characteristics of plates with straight bars compared to curved bar plates having the same bar parameters during refining. The objective of this research is to explore the difference in the refining characteristics of the straight bar and curved bar plates on experimental and theoretical studies. The bar angle of the curved bar plate is defined, and the two plates are used in the refining of bleached sulphate eucalyptus pulp (BSEP). Samples at different refining times were collected, and the properties of the fibers, pulp, and paper were detected and analyzed. It was found that the curved bar and straight bar plates have a similar influence on the pulp SR freeness. However, the curved bar plate effectively retained the fiber length, which means that its fiber cutting effect is weaker than that of the straight bar plate. Meanwhile, the fiber external fibrillation of the samples refined by the curved bar plate was better than that of the samples refined by the straight bar, which showed a higher tensile and tear index of the formed paper. Through the theoretical analysis of refining intensity via characterization of the parameter bar edge length (BEL), the specific edge load (SEL) of the curved bar plate was lower, and the refining characteristics predicted by the refining intensity were similar to the results from the experiments conducted in this paper.

The Influence of Entrepreneurial Leadership on Team Performance – Focusing on the Mediating Role of Team Efficacy

Huan-Huan Wang,Yan-Nan LI,Jong-Kwan Kim 한국디지털정책학회 2020 디지털융복합연구 Vol.18 No.10

Enhanced Removal of Phenol from Aquatic Solution in a Schorl-catalyzed Fenton-like System by Acid-modified Schorl

Huan-Yan Xu,Murari Prasad,Peng Wang 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.4

Schorl modified by H₂SO4 has been successfully developed to enhance schorl-catalyzed Fenton-like reaction for removal of phenol in an aqueous solution. The phenol removal percentage can be increased from 4% to 100% by the system of modified schorl and H₂O₂. Batch experiments indicate that the percent increases in removal of phenol by increasing the dosage of catalyst, temperature and initial concentration of H₂O₂. The results of XRD, FT-IR and SEM suggest that no new phases are formed after removal of phenol by modified schorl. ICP-AES results reveal that more dissolution of iron results in higher catalytic oxidant activity in the system of modified schorl and H₂O₂. Besides minor adsorption, mineralcatalyzed Fenton-like reaction governs the process.

Experimental investigation of crack growth behaviors and mechanical properties degradation during gear bending fatigue

Huan Yan,Peitang Wei,Pengliang Zhou,Ling Chen,Huaiju Liu,Caichao Zhu 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.3

Tooth bending fatigue remains as a fundamental bottleneck restricting the safety and reliability of modern high-performance gear. In this study, a serial of bending fatigue tests on case carburized and shot peening treated gears is conducted. The fatigue crack propagation behaviors during bending fatigue test were analyzed. The alternations of macroscopic mechanical properties and microstructure features of gear samples subjected to bending fatigue are experimentally examined and analyzed in detail. It is found that the measured tooth root crack trajectories basically conform to the dangerous section of the tooth root determined by the 30° tangent method with a slight variation of about 1°. The phenomena of residual stress relaxation in gear bending fatigue is observed with the maximum residual compressive stress decreasing from -698 MPa of intact state to -572 MPa of failure state. Furthermore, the content of retained austenite of tooth root surface decreases by about 3.8 % after the gear bending fatigue failure, and the grain size of the tooth root core region illustrates a certain tendency of coarsening.

Iron-loaded Natural Clay as Heterogeneous Catalyst for Fenton-like Discoloration of Dyeing Wastewater

Huan-Yan Xu,Xiu-Lan He,Ze Wu,Lian-Wei Shan,Wei-Dong Zhang 대한화학회 2009 Bulletin of the Korean Chemical Society Vol.30 No.10

The clay-based Fe-bearing catalyst was successfully prepared through ion-exchange reaction and applied as heterogeneous catalyst for discoloration of acid fuchsine (AF) in an aqueous solution by Fenton-like action.Experimental results demonstrated that the AF discoloration ratios increased by increasing Fe-loaded clay dosage and initial H2O2 concentration, and by decreasing the pH, respectively. The lower the initial AF concentration, the shorter the reaction time needed to achieve complete discoloration of AF. Comparative studies indicated that AF discoloration ratios were much higher in presence of Fe-loaded clay and H2O2 than those in presence of H2O2, raw natural clay or Fe-loaded clay only and raw natural clay and H2O2 jointly. After AF discoloration, there existed no new phases in the clay samples detected by XRD and no change in the clay crystal morphology observed by SEM. A mechanism proposed suggested adsorption and Fenton-like reaction were responsible for discoloration of AF.

Feeding and related morphology of salivary glands of Bradysia odoriphaga (Diptera: Sciaridae)

Huan-Huan Gao,Yi-Fan Zhai,Xue Cao,Xian-Hong Zhou,Zhong-Yan Wang,Fang Wang,Hao Chen,Yi Yu 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.2

The amount of Bradysia odoriphaga larval feeding at each developmental stage and the related morphology of salivary glands were investigated in this study. The amount of daily feeding in the third instar was greatest among all the developmental stageswhile the amount of cumulative feeding in the fourth-instar accounted for 53.56% of the total amount of larval feeding. The daily amount of feeding by B. odoriphaga during the whole larval stage peaked in the 8th and 14th day after hatching. The paired and transparent salivary glands of B. odoriphaga were characterized by two distinct regions: an anterior region and a posterior region. At the fourth-instar and pupal stage, the length of salivary glands decreased significantly compared with that of the third-instar, and the integrity of epithelium cytoplasm in the salivary glands also decreased markedly because of the formation of cytoplasmic vacuoles and degradation of rough endoplasmic reticulum and mitochondria. We concluded that the decrease of daily feeding amount in the last instar was related to the structural change of salivary gland closely. The function of salivary glands in B. odoriphaga was mainly secretion of silk and cocooning-like materials during the last larval instar.

Analysis of the Baroreceptor and Vestibular Receptor Inputs in the Rostral Ventrolateral Medulla following Hypotension in Conscious Rats

Yan Lan,Huan-Jun Lu,Xian Jiang,Li-Wei Li,Yan-Zhao Yang,Guang-Shi Jin,박주영,김민선,박병림,Yuan-Zhe Jin 대한약리학회 2015 The Korean Journal of Physiology & Pharmacology Vol.19 No.2

Input signals originating from baroreceptors and vestibular receptors are integrated in the rostralventrolateral medulla (RVLM) to maintain blood pressure during postural movement. The contributionof baroreceptors and vestibular receptors in the maintenance of blood pressure following hypotensionwere quantitatively analyzed by measuring phosphorylated extracellular regulated protein kinase(pERK) expression and glutamate release in the RVLM. The expression of pERK and glutamate releasein the RVLM were measured in conscious rats that had undergone bilateral labyrinthectomy (BL)and/or sinoaortic denervation (SAD) following hypotension induced by a sodium nitroprusside (SNP)infusion. The expression of pERK was significantly increased in the RVLM in the control groupfollowing SNP infusion, and expression peaked 10 min after SNP infusion. The number of pERKpositive neurons increased following SNP infusion in BL, SAD, and BL+SAD groups, although theincrease was smaller than seen in the control group. The SAD group showed a relatively higherreduction in pERK expression when compared with the BL group. The level of glutamate release wassignificantly increased in the RVLM in control, BL, SAD groups following SNP infusion, and thispeaked 10 min after SNP infusion. The SAD group showed a relatively higher reduction in glutamaterelease when compared with the BL group. These results suggest that the baroreceptors are morepowerful in pERK expression and glutamate release in the RVLM following hypotension than thevestibular receptors, but the vestibular receptors still have an important role in the RVLM.

Analysis of the Baroreceptor and Vestibular Receptor Inputs in the Rostral Ventrolateral Medulla following Hypotension in Conscious Rats

Lan, Yan,Lu, Huan-Jun,Jiang, Xian,Li, Li-Wei,Yang, Yan-Zhao,Jin, Guang-Shi,Park, Joo Young,Kim, Min Sun,Park, Byung Rim,Jin, Yuan-Zhe The Korean Society of Pharmacology 2015 The Korean Journal of Physiology & Pharmacology Vol.19 No.2

Input signals originating from baroreceptors and vestibular receptors are integrated in the rostral ventrolateral medulla (RVLM) to maintain blood pressure during postural movement. The contribution of baroreceptors and vestibular receptors in the maintenance of blood pressure following hypotension were quantitatively analyzed by measuring phosphorylated extracellular regulated protein kinase (pERK) expression and glutamate release in the RVLM. The expression of pERK and glutamate release in the RVLM were measured in conscious rats that had undergone bilateral labyrinthectomy (BL) and/or sinoaortic denervation (SAD) following hypotension induced by a sodium nitroprusside (SNP) infusion. The expression of pERK was significantly increased in the RVLM in the control group following SNP infusion, and expression peaked 10 min after SNP infusion. The number of pERK positive neurons increased following SNP infusion in BL, SAD, and BL+SAD groups, although the increase was smaller than seen in the control group. The SAD group showed a relatively higher reduction in pERK expression when compared with the BL group. The level of glutamate release was significantly increased in the RVLM in control, BL, SAD groups following SNP infusion, and this peaked 10 min after SNP infusion. The SAD group showed a relatively higher reduction in glutamate release when compared with the BL group. These results suggest that the baroreceptors are more powerful in pERK expression and glutamate release in the RVLM following hypotension than the vestibular receptors, but the vestibular receptors still have an important role in the RVLM.

Enhanced Removal of Phenol from Aquatic Solution in a Schorl-catalyzed Fenton-like System by Acid-modified Schorl

Xu, Huan-Yan,Prasad, Murari,Wang, Peng Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.4

Schorl modified by $H_2SO_4$ has been successfully developed to enhance schorl-catalyzed Fenton-like reaction for removal of phenol in an aqueous solution. The phenol removal percentage can be increased from 4% to 100% by the system of modified schorl and $H_2O_2$. Batch experiments indicate that the percent increases in removal of phenol by increasing the dosage of catalyst, temperature and initial concentration of $H_2O_2$. The results of XRD, FT-IR and SEM suggest that no new phases are formed after removal of phenol by modified schorl. ICP-AES results reveal that more dissolution of iron results in higher catalytic oxidant activity in the system of modified schorl and $H_2O_2$. Besides minor adsorption, mineral-catalyzed Fenton-like reaction governs the process.

해경(海景)이 주택가격에 미치는 영향에 관한 연구

장연연(Yan yan Zhang),주환보(Huan bao Zhou),판강지(Gang zhi Fan) 건국대학교 부동산도시연구원 2016 부동산 도시연구 Vol.9 No.1

해안가 주변의 주택은 다른 지역에 비해 더 높은 가격을 형성함에도 불구하고 사람들은 투자나 거주의 목적으로 해안가 주변의 주택을 선호한다. 따라서 본 연구에서는 중국 칭다오시의 부동산 거래 데이터를 기반으로 주택 가격 결정모형을 이용하여 바다 조망권이 부동산 가격에 미치는 영향에 대하여 연구하였다. 바다 조망권은 세 가지 측면에서 측정한다. 주택이 바다를 바라보는 방향, 내부에서 바다를 바라볼 수 있는지, 주택 자체가 바다근처에 위치하고 있는지를 고려한다. 본 연구의 결과에 따르면 바다 전망은 칭다오시 주택 가격에 통계적으로 유의한 정(+)의 영향을 미친다. 우리의 연구 결과는 칭다오시 정부가 도시의 부동산 산업의 건전한 발전을 위한 주택 정책을 만들 수 있도록 도움이 될 것이다. 또한 이러한 연구 결과는 중국에 있는 항구 도시에서 주택 가격 결정을 조명하는데 도움이 된다. Houses near an ocean usually have higher prices than those that are not. This paper attempts to further investigate this phenomenon by focusing on the impact of ocean-front view on housing price using the housing transaction data collected from Qingdao s real estate market through the hedonic pricing model. We measure the features of ocean-front view from three dimensions, namely orientation to ocean, ocean view visibility and proximity to ocean. Our regression results clearly show that ocean-front view has a significant positive impact on the prices of residential properties, implying the importance of ocean-front view in the determination of housing prices.