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Curing Kinetics of Tannin and Lignin Biobased Adhesives Determined by DSC and ABES

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Journal of Renewable materials 2022年第8期10卷 2117-2131页

作者： jaša saražin Ida Poljanšek Antonio Pizzi milanŠernek university of Ljubljana Biotechnical FacultyLjubljana1000Slovenia universitéde Lorraine LERmaB-ENSTIB Epinal88000France

The curing process of two biobased adhesives:pine tanninhexamine(TH)and organosolv lignin non-isocyanate polyurethane(NIPU),suitable for interior nonstructural use,were compared with commercial urea-formaldehyde(UF)*** in chemical structure before and after the curing process were observed with Fouriertransform infrared spectroscopy(FTIR).The process of adhesive curing was monitored with differential scanning calorimetry(DSC)and the automated bonding evaluation system(ABES).Both DSC and ABES measurements confirmed UF as the fastest and NIPU as the slowest curing adhesive *** into account the ABES results,the optimal pressing parameters for the TH adhesive would be 4 min at 175℃,for the NIPU adhesive 7 min at 200℃and for the UF 1.5 min at 100℃.Strong linear correlation was observed between mechanical and chemical curing for the UF and NIPU adhesives,whereas lower correlation was observed for the TH *** all observed adhesives,the DSC measurements were underestimating the curing process determined by ABES in the first part and overestimating it at the *** underestimation was the most evident with the TH adhesive and the less with the UF *** comparing the uncured and cured FTIR spectra of all three types of adhesives,a drastic decrease in the characteristic band of-OH groups at 3330–3400 cm^(−1)and an increase in the signal intensity at 2920 cm^(−1)of aliphatic-CH2-groups were *** the UF adhesive,the C=O stretching frequency has shifted from 1632 cm^(−1)for uncured to three different bands at 1766,1701,and 1655 cm^(−1)for cured *** sharp band for phenolic alcohols at 1236 cm^(−1)of C–O stretch and hydroxyl O–H functional group at 1009 cm^(−1)and at 684 cm^(−1)of uncured TH adhesive diminished during curing,which indicates that a crosslinking reaction occurs via-OH *** peak of the C=O group of urethane bridges at 1697 cm^(−1)for uncured NIPU shifted to lower wavenumber at 1633 cm^(−1)for cured NIPU.

关键词： Biobased adhesives curing kinetics tannin lignin ABES DSC FTIR

Heterogeneous photo-assisted Fenton catalytic removal of tetracycline using Fe-Ce pillared bentonite

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Journal of Central South university 2014年第1期21卷 310-316页

作者：张亚平贾成光彭然马丰欧光南 College of Biology Engineering Jimei University

In the present work, a novel heterogeneous photo-Fenton catalyst was prepared by iron and cerium pillared bentonite. The catalyst Fe-Ce/bentonite was characterized by X-ray diffraction （XRD）, X-ray fluorescence （XRF）, Brunauer-Emmett-Teller （BET） and scanning electron microscopy （SEm） methods. It is found that Fe and Ce intercalate into the silicate layers of bentonite successfully. Tetracycline was removed by heterogeneous photo-Fenton reaction using the catalyst in this work. The effects of different reaction systems, hydrogen peroxide concentration, initial pH, catalyst dosage, UV power and introduction of different anions on degradation were investigated in details. The stability of catalyst was investigated through recycling experiment. The results show that removal rate of tetracycline is 98.13% under the conditions of 15 mmol/L H202, 0.50 g/L catalyst dosage, initial pH 3.0, 11 W UV lamp power and 60 min reaction time. However, the removal rate decreases after adding some anions. The hydroxyl radical plays an important role in heterogeneous photo-assisted Fenton degradation of tetracycline. The catalyst is very stable and can be recycled many times.

关键词： wastewater treatment advanced oxidation process photo-Fenton antibiotics Fe-Ce/bentonite

Coastal landscape evolution tracked from late Holocene wave-cut benches in the Sinan Archipelago,Southwest Korea

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Geoscience Frontiers 2020年第1期11卷 293-301页

作者： Sung-ja Choi Bokchul Kim Yong Sik Gihm sanghoon Kwon Geology Division Korea Institute of Geoscience and Mineral ResourcesDaejeon34132Republic of Korea Department of Earth System Sciences Yonsei UniversitySeoul03722Republic of Korea School of Earth Sciences The Ohio State UniversityColumbusOH43210USA

Glacio-isostatic adjustment(GIA)and tectonic activity are important factors in the formation of marine *** Holocene wave-cut benches in the eastern part of the West Sea of Korea,also called the Yellow Sea,can be divided into two steps:531 cm above sea level(ASL)for the upper bench(T2)and 464-481 cm ASL for the lower bench(T1).Sediments on the benches a re classified into four units,and are interpreted to be beach deposits acco rding to gravel shape,textu re,and seaward *** ove rlying sediment indicates that T2 was formed at approximately 530 cm ASL before 2900 yr BP,and T1 at approximately 460-480 cm ASL before 1520 yr *** Holocene(4000-2000 yr BP)relative sea level(RSL)curves based on GIA models are inconsistent with the wave-cut bench *** T1 and T2 benches to the RSL curves of the West Sea,the upper and the lower benches were uplifted by approximately 5-8 m and 4-7 m,*** the area is several hundred kilometers away from plate boundaries,the high frequency of earthquakes in the West Sea may have induced the uplift of wave-cut benches during the last 2000 *** indicate that the west coast of the Korean Peninsula(KP)should no longer be considered an area of subsidence,but be assigned to a regime of uplift during the late Holocene.

关键词： West Sea of Korea Yellow Sea Late Holocene Wave-cut benches Beach sediment Uplift Tectonics

Developments in diagnosis and treatment of paediatric septic arthritis

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World Journal of Orthopedics 2022年第2期13卷 122-130页

作者： Cornelia m Donders Anne J Spaans Herbert van Wering Christiaan ja van Bergen Department of Orthopaedic Surgery Meander Medical CentreAmersfoort 3813 TZNetherlands Department of Orthopaedic Surgery Sint MaartenskliniekNijmegen 6574 NANetherlands Department of Paediatrics Amphia HospitalBreda 4818 CKNetherlands Department of Orthopedic Surgery Amphia HospitalBreda 4818 CKNetherlands

Acute septic arthritis in children is an orthopaedic emergency.A delay in diagnosis and inappropriate treatment can result in devastating damage to the joint with lifelong disability as a *** clinical presentation can be a diagnostic challenge,especially in young children.A recent systematic review showed that joint tenderness and fever are important signals of septic *** is helpful in detecting the presence of a joint *** radiographs may show bone changes but magnetic resonance imaging is the most reliable imaging study for detecting concomitant *** diagnosis of acute septic arthritis is highly suggestive when pus is aspirated from the joint,in case of a positive culture or a positive gram stain of the joint fluid,or if there is a white blood-cell count in the joint fluid of more than 50000/*** aureus is the most commonly cultured *** systematic reviews have identified the most effective drainage techniques,including needle aspiration,arthroscopy and arthrotomy,depending on the affected *** the drainage procedure it is important to monitor the clinical and laboratory *** drainage procedures may be necessary in select cases.

关键词： Septic arthritis Paediatric Children Analysis Treatment Drainage

CD24 expression predicts distant metastasis in extrahepatic bile duct cancer

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World Journal of Gastroenterology 2013年第9期19卷 1438-1443页

作者： Kyubo Kim Hye Sook min Eui Kyu Chie Jin-Young jang Sun Whe Kim sae-Won han Do-Youn Oh Seock-Ah Im Tae-You Kim Yung-Jue Bang ja-June jang Sung W ha Department of Radiation Oncology Seoul National University College of Medicine Seoul 110-744 South Korea Department of Pathology Seoul National University College of Medicine Seoul 110-744 South Korea Institute of Radiation medicine Medical Research Center Seoul National University Seoul 151-742 South Korea Department of Surgery Seoul National University College of Medicine Seoul 110-744 South Korea Department of Internal medicine Seoul National University College of Medicine Seoul 110-744 South Korea

AIm: To evaluate the prognostic significance of CD24 expression in patients undergoing adjuvant chemoradiotherapy for extrahepatic bile duct (EHBD) cancer. mETHODS: Eighty-four patients with EHBD cancer who underwent curative resection followed by adjuvant chemoradiotherapy were enrolled in this study. Postoperative radiotherapy was delivered to the tumor bed and regional lymph nodes up to a median of 40 Gy (range: 40-56 Gy). All patients also received fluoropyrimidine chemotherapy for radiosensitization during radiotherapy. CD24 expression was assessed with immunohistochemical staining on tissue microarray. Clinicopathologic factors as well as CD24 expression were evaluated in multivariate analysis for clinical outcomes including loco-regional recurrence, distant metastasisfree and overall survival. RESULTS: CD24 was expressed in 36 patients (42.9%). CD24 expression was associated with distant metastasis, but not with loco-regional recurrence nor with overall survival. The 5-year distant metastasis-free survival rates were 55.1% and 29.0% in patients with negative and positive expression, respectively (P=0.0100). On multivariate analysis incorporating N stage, histologic differentiation and CD24 expression, N stage was the only significant factor predicting distant metastasis-free survival (P=0.0089), while CD24 expression had borderline significance (P=0.0733). In subgroup analysis, CD24 expression was significantly associated with 5-year distant metastasis-free survival in node-positive patients (38.4% with negative expression vs 0% with positive expression, P=0.0110), but not in nodenegative patients (62.0% with negative expression vs 64.0% with positive expression,P=0.8599). CONCLUSION: CD24 expression was a significant predictor of distant metastasis for patients undergoing curative resection followed by adjuvant chemoradiotherapy especially for node-positive EHBD cancer.

关键词： CD24 Tissue microarray Extrahepatic bile duct cancer Adjuvant chemoradiotherapy Distant metastasis

Involvement of NAC transcription factor NaNAC29 in Alternaria alternata resistance and leaf senescence in Nicotiana attenuata

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Plant Diversity 2021年第6期43卷 502-509页

作者： Lan ma Rongping Li Luoyan ma Na Song Zhen Xu Jinsong Wu Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of BotanyChinese Academy of SciencesLanhei Road 132650201KunmingChina university of Chinese Academy of Science Beijing 100049China

NAC-LIKE,ACTIVATED BY AP3/PI(NAP)is a NAC transcription factor regulating leaf senescence in Arabidopsis *** wild tobacco Nicotiana attenuata,a nuclear localized NAC transcription factor NaNAC29 was identified to be highly elicited after inoculation of Alternaria alternata,a notorious necrotic fungus on tobacco *** NaNAC29 possesses similar tertiary structure to NAP with 60%amino acid ***,it remains unknown the role of NaNAC29 in plant defense responses to *** and leaf senescence in *** this paper,Defensin-like protein 1(NaDLP1)was highly induced in *** after *** inoculation and bigger lesions were developed in NaDLP1-silenced ***,***-induced NaDLP1 was reduced by 76%in VIGS NaNAC29 plants and by 61%in ja deficient irAOC plants at 3 days post *** regulation of NaDLP1 expression by NaNAC29 was clearly independent on ja pathway,since exogenous methyl jasmonate treatment could not complement the induction levels of NaDLP1 in NaNAC29-silenced plants to the levels in WT ***,the expression of NaNAC29 was low expressed in young leaves but highly in senescent leaves and darktreated ***29-silenced plants,which were generated by virus-induced gene silencing(VIGS NaNAC29),showed delayed senescence *** addition,constitutive over-expression of NaNAC29 in *** could rescue the delayed-senescence phenotype of nap and caused precocious leaf senescence of wild-type Col-0 *** the data above demonstrate that NaNAC29 is a NAP homolog in *** participating in the defense responses to *** by regulation of a defensin protein NaDLP1 and promoting leaf senescence.

关键词： NaNAC29 Defensin-like protein 1 Tobacco Brown spot disease Aging

The protective effect of caffeine on DNA photosensitive damage:A gel electrophoresis

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Nuclear Science and Techniques 2009年第4期20卷 223-227页

作者： HUANG Liping ma Jianhua College of Biology Engineering Jimei University Xiamen 361021 China

Agarose gel electrophoresis was performed to study interaction effect of caffeine on photosensitive injury of DNA caused by anthraquinone-2-sulphonic acid disodium(AQS),a model compound of strong photosensitizer,under 254 nm or 365nm UV irradiation Photosensitive injury of DNA induced by AQS under deoxidized condition was used as *** results show that caffeine may resist effectively the injury effect of photosensitive damage and strong UV irradiation on *** effects depend on the caffeine and AQS concentration,and irradiation *** in concentration of 0.01-3.0μg/μL,may prevent DNA from damage induced by UV light,but caffeine in concentration of>5.0μg/μL accelerates the DNA *** particular,in the aqueous solution system of DNA,caffeine and AQS,at pH 6.25-7.35,the caffeine in concentration of 2.5-4.50μg/μL may resist the photosensitive injury of DNA caused by AQS under the deoxidized condition and exposure by 254 nm UV for 10 *** caffeine in concentration of 5μg/μL would present a synergetic effect on the photosensitive injury of *** molecular mechanism also is discussed.

关键词：凝胶体电泳 DNA UV照射核技术

Identity（Re） Construction and the Sense of Belongingness among International Students in China:A Case Study of Zhejiang Normal university

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Identity（Re） Construction and the Sense of Belongingness a...

作者： ja ZIN 浙江师范大学

学位级别：硕士

Discussion about international students in China is a topic with a long history and different *** the development of the socio-economy of China,the number of international students in China grows faster than *** number of International Students coming to China is adhesively increasing,though summative with a lot of challenges faced during their studies and majorly accruing from ***,their life experiences and identity issues deserve more attention that it already hadIdentity is now defined as a self-concept,self-perception,both individual and social-cultural,and that may develop over time regarding to a group which they belong to,such as a particular student in Chinese *** is an individual’s sense of belonging to a group;this belonging offers a feeling of security and *** identity（re）construction is mostly shaped by both historical and cultural *** the theoretical framework combining social identity theory（Tajfel,1974）and maslow’s（1943）theory of human motivation,this thesis investigated the identity construction and sense of belongingness of international students in Zhejiang Normal university as a case *** study utilized combining semi-structured interviews and a thematic analysis to examine the intercultural experiences of ten international students through their own *** themes were uncovered and further discussed on findings as the participants shared stories about the difficulties,they have been challenged with such as cultural misunderstanding,academic achievement,social acceptance,identity confusion,and other societal pressures and *** students encountered various problems in both their academic and social life.

关键词：国际学生归属感师范大学

Organosolv Lignin for Non-Isocyanate Based Polyurethanes (NIPU) as Wood Adhesive

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Journal of Renewable materials 2021年第5期9卷 881-907页

作者： jaša saražin Antonio Pizzi Siham Amirou Detlef Schmiedl milanŠernek Biotechnical Faculty University of LjubljanaLjubljana1000Slovenia LERmaB-ENSTIB Universitéde LorraineEpinal88000France Fraunhofer Institute for Chemical Technology Pfinztal76327Germany

A non-isocyanate-based polyurethane(NIPU)wood adhesive was produced from organosolv lignin,which is a bio-sourced raw material,available in large quantities and produced as a by-product of the paper *** formulation of this new lignin-based NIPU adhesive,which is presented,was chemically characterised by matrix-Assisted Laser Desorption Ionization Time of Flight(maLDI ToF)mass spectrometry and by Fourier Transform Infra-Red(FTIR)spectrometry *** oligomers formed were determined and showed that the three species involved in the NIPU adhesive preparation were formed by the co-reaction of the three reagents used:lignin,dimethyl carbonate,and hexamethylene *** and branched structures were both *** properties of the adhesive were determined using the Automated Bonding Evaluation System(ABES)and internal bond(IB)strength test of the laboratory particleboard bonded with *** adhesive has shown satisfactory mechanical properties after hot pressing at 230℃.Such a temperature is used industrially in the most modern particleboard factories,but since it is hardly feasible for more conventional wood bonding equipment,the reactivity of the NIPU adhesive was successfully increased with the addition of a small percentage of a silane coupling *** the addition of the silane,the proposed NIPU adhesive could also be used at a hot-pressing temperature lower than 200℃.

关键词： Organosolv lignin NIPU maLDI ToF FTIR ABES