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A convenient method for measuring gas-liquid volumetric mass transfer coefficient in micro reactors

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Chinese Chemical Letters 2024年第4期35卷 389-392页

作者： haoyang wang Ronghao Zhang Yanlun Ren Li Zhang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

The research on gas-liquid multiphase reactions using micro reactors is becoming increasingly widespread, given their excellent mass transfer performance. Establishing an accurate and reliable method to measure the gas-liquid mass transfer performance of micro reactors is crucial for evaluating and optimizing the design of micro reactor structure. In this paper, the physical absorption method of aqueous solution-CO_(2) and the chemical absorption method of sodium carbonate solution-CO_(2) were proposed. By analyzing the chemical reaction equilibrium during the absorption process, the relationship between the mass transfer of CO_(2) and the solubility of hydroxide ions in the solution was established, and the total gas-liquid mass transfer coefficient was immediately obtained by measuring the p H value. The corresponding testing platform and process have been established based on the characteristics of the proposed method to ensure fast and accurate measurement. In addition, the chemical absorption method takes into account temperature factors that were not previously considered. The volumetric mass transfer coefficient measured by these two methods is in the same range as those measured by other methods using the same microchannel structure in previous literature. The methods have the advantages of low equipment cost, faster measurement speed, and simpler procedures, which can facilitate its wide application to the evaluation of the mass transfer performance and hence can guide the structure optimization of microchannel reactors.

关键词： Volumetric mass transfer coefficient measurement Gas-liquid two phase Micro reactors Physical absorption Chemical absorption

Study of the Transient Reactive Pd(Ⅳ) Intermediate in the Pd(OAc)2-Catalyzed Oxidative Coupling Reaction System by Electrospray Ionization Tandem Mass Spectrometry

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Chinese Journal of Chemistry 2013年第3期31卷 371-376页

作者： Wei Zhu haoyang wang Haihui Peng Guosheng Liu Yinlong Guo Shanghai Mass Spectrometry Center Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Pd-catalyzed oxidative coupling reaction was of great importance in the aromatic C--H activation and the for-mation of new C-O and C--C bonds. Sanford has pioneered practical, directed C-H activation reactions em-ploying Pd（OAc）2 as catalyst since 2004. However, until now, the speculated reactive Pd（Ⅳ） transient intermedi-ates in these reactions have not been isolated or directly detected from reaction solution. Electrospray ionization tandem mass spectrometry （ESI-MS/MS） was used to intercept and characterize the reactive Pd（Ⅳ） transient inter-mediates in the solutions of Pd（OAc）2-catalyzed oxidative coupling reactions. In this study, the Pd（IV） transient in-termediates were detected from the solution of Pd（OAc）2-catalyzed oxidative coupling reactions by ESI-MS and the MS/MS of the intercepted Pd（IV） transient intermediate in reaction system was the same with the synthesized au-thentic Pd（Ⅳ） complex. Our ESI-MS（/MS） studies confirmed the presence of Pd（Ⅳ） reaction transient intermedi-ates. Most interestingly, the MS/MS of Pd（Ⅳ） transient intermediates showed the reductive elimination reactivity to Pd（Ⅱ） complexes with new C-O bond formation into product in gas phase, which was consistent with the proposed reactivity of the Pd（Ⅳ） transient intermediates in solution.

关键词： electrospray ionization tandem mass spectrometry (ESI-MS/MS) Pd(IV) transient intermediate oxi^dative coupling reaction

A Polysaccharide-based Hydrogel and PLGA Microspheres for Sustained P24 Peptide Delivery: An In vitro and In vivo Study Based on Osteogenic Capability

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Chemical Research in Chinese Universities 2019年第5期35卷 908-915页

作者： CAI Qing QIAO Chunyan NING Jun DING Xinxin wang haoyang ZHOU Yanmin Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling School of StomotologyJilin UniversityChangchun 130021P.R.China The First Hospital of Jilin University Changchun 130021P.R.China

A bone morphogenetic protein-2(BMP-2) derived synthetic oligopeptide, S [PO4]KIPKASSVPTELSAISTLYLDDD(P24), has shown great potential for facilitating bone regeneration. However, P24 cannot be directly used onto bone defects, while a continuous sustained delivery of P24 may lead to a better formation of bone tissue. Based on this issue, we have developed a sustained delivery system incorporating P24-loaded poly(lactide-co-glycolide)(PLGA) microspheres and nano-hydroxyapatite(n-HA) into the composite hydrogel. The P24-contained compound material was characterized with NMR, FTIR and SEM to demonstrate the fomiation of compound structure containing P24, PLGA and n-HA. A continuous drug release of P24 was observed for over 60 d that evidently enhanced the efficiency in promoting the proliferation of MC3T3-E1 cells and the secrete of alkaline phosphatase(ALP) in vitro. Moreover, the osteoinduction eflect of the hydrogel system with P24 peptide niicrospheres was demonstrated in vivo and manifested by the result of immunohistochemistry. This novel injectable composite hydrogel is expected to be applied to improving the bone defect treatment in bone tissue engineering.

关键词： BMP-2 derived peptide Hydrogel PLGA microsphere Osteogenesis Tissue engineering

Biochar addition to tea garden soils:effects on tea fluoride uptake and accumulation

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Biochar 2023年第1期5卷 641-656页

作者： haoyang wang Teng Hu Minghan wang Yunshan Liang Chengwen Shen Huaqin Xu Yaoyu Zhou Zhonghua Liu College of Resources and Environment Hunan Agricultural UniversityChangsha 410128HunanChina Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area Changsha 410128HunanChina Key Laboratory of Tea Science of Ministry of Education Hunan Agricultural UniversityChangsha 410128HunanChina National Research Center of Engineering and Technology for Utilization of Functional Ingredients From Botanicals Collaborative Innovation Center of Utilization of Functional Ingredients From BotanicalsHunan Agricultural UniversityChangsha 410128HunanChina

Long-term consumption of tea with high fluoride(F)content has a potential threat to human *** application of different amounts of biochar to reduce F accumulation in tea leaves has been little *** this study,a pot experiment was conducted to investigate the effect of biochar amounts(0,0.5%,2.5%,5.0%,8.0%,and 10.0%,w/w)on tea F content during the tea plant *** in tea quality,soil F fraction,and soil properties caused by biochar and the relationship with tea F accumulation were also *** results showed that the application of biochar amendment significantly reduced water-soluble F contents in tea leaves compared to CK(without biochar),especially in the 8.0%treatment(72.55%).Overall,biochar contributed to improving tea polyphenols and caffeine,but had no significant impact on free amino acids and water *** with CK,5.0-10.0%biochar significantly increased soil water-soluble F content due to the substitution of F−with OH−under high ***,biochar applied to tea garden soil was effective in decreasing the soil exchangeable aluminum(Ex-Al)content(46.37-91.90%)and increasing the soil exchangeable calcium(Ca^(2+))content(12.02-129.74%)compared to CK,and correlation analysis showed that this may help reduce F enrichment of tea *** general,the application of 5.0-8.0%biochar can be suggested as an optimal application dose to decrease tea F contents while simultaneously improving tea quality.

关键词： Fluoride Biochar Tea quality Fluoride fractions Fluoride-aluminum complexes

Behaviors of Leucine and Isoleucine in Ion Mobility- Quadrupole Time of Flight Mass Spectrometry

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Chinese Journal of Chemistry 2015年第12期33卷 1359-1364页

作者： Su Guo Fang Zhang haoyang wang Manyu Zhang Zhixu Zhang Xiang Zhang Yinlong Guo National Center for Organic Mass Spectrometry in Shanghai Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China Agilent Technologies (China) CO. Ltd. 1350 North Sichuan Road Shanghai 200080 China Department of Chemistry Fudan University 220 Handan Road Shanghai 200433 China School of Food Science and Biotechnology Zhejiang Gongshang University Hangzhou Zhejiang 310018 China

In this study, ion mobility separation coupled with tandem mass spectrometry （IM-tandem MS） was utilized to investigate the ionization behaviors of two amino acids including leucine and isoleucine. Under the electrospray ionization （ESI） mode, two protonation sites in each molecular sturcture caused two forms of protomer. One arose from the amino being protonated （amino-protomer） and the other from the carboxyl being protonated （car- boxyl-protomer）. In the two-dimensional （drift time, m/z） spectrum, the protomers had the same mass, but the dis- tinguishable drift times and fragmentation patterns. For the characterization purpose, the theoretical collision cross section （CCS） values of the protomers were calculated and proven to be consistent with the experimental. Moreover, the quantified relationship between the amino acids and their protomers was evaluated. It showed that the abun- dance of the carboxyl-protomer was proportional to the concentration of the amino acid, whereas that of the amino- protomer did not have the same trend. Under the atmospheric pressure chemical ionization （APCI） mode, only the carboxyl-protomer was observed. In addition, the amino-protomer and the cluster ions observed under ESI were absent completely. The results demonstrate that the ionization mode impacts heavily on the ionization behaviors of leucine and isoleucine not only on the form of therir protomers but also On the quantified relationship.

关键词： leucine isoleucine IM-tandem MS ESI APCI

Reliable screening of pesticide residues in maternal and umbilical cord sera by gas chromatography-quadrupole time of flight mass spectrometry

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Science China Chemistry 2014年第5期57卷 669-677页

作者： FAN RuoJing ZHANG Fang wang haoyang ZHANG Li ZHANG Jing ZHANG Ying YU ChongTian GUO YinLong Shanghai Mass Spectrometry Center Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Department of Gynaecology and Obstetrics Yijishan Hospital of Wannan Medical College Agilent Technologies (China) CO. Ltd.

The widespread use of pesticides induces heavy adverse effects on human health,especially for the pregnant women and the *** this study,a screening method has been developed for the determination of multi-pesticides in maternal and umbilical cord *** pesticides in sera were collected using solid phase extraction(SPE),and analyzed by gas chromatography-quadrupole time of flight mass spectrometry(GC-QTOF MS).To set up the quality criteria,a database of 50 pesticides was created and the accurate masses of 3 up to 5 representative ions with their intensity ratios were included for each *** addition,a novel"identification points"(IPs)system relying on the accurate MS1 and MS2 spectra was used to interpret the data for each suspected *** methodology was then applied to a pair of maternal and umbilical cord sera.A total of six pesticide residues were screened out *** conclusion,GC-QTOF MS combined with an accurate mass database seemed to be one of the most efficient tools for systematic pesticide analysis.

关键词： pesticide residues screening maternal and umbilical cord sera gas chromatography-quadrupole time of flight massspectrometry

Combination of Solid-Phase Micro-Extraction and Direct Analysis in Real Time-Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for Sensitive and Rapid Analysis of 15 Phthalate Plasticizers in Beverages

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Chinese Journal of Chemistry 2015年第2期33卷 213-219页

作者： Mengxi Wu haoyang wang Guoqing Dong Brian D.Musselman Charles C.Liu Yinlong Guo Shanghai Mass Spectrometry Center Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China IonSense Inc.999 BroadwaySuite 404SaugusMA 01906USA ASPEC Technologies Limited Room 1506RunFengDeShang Bldg ANo.60 An Li LuChaoyang DistrictBeijing 100101China

A method for rapid identification and quantification of phthalate plasticizers in beverages was developed.A number of 15 phthalate plasticizers which covered all the phthalates concerned in the US Consumer Product Safety Improvement Act(CPSIA),European Union legislations and Chinese national standards(GB)were *** a combined solid-phase micro-extraction(SPME)and direct analysis in real time mass spectrometry(DART-MS)approach,phthalates at sub-ng•mL^(−1)levels can be qualitatively and quantitatively analyzed in a short *** use of ultrahigh-resolving power and the accurate mass measurement capacity naturally provided by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS)minimizes the matrix interferences and thus enables the evaluation of phthalates in a complex matrix without extensive sample handlings or *** limits of quantification(LOQs)were estimated to be at 0.3-5.0 ng•mL^(−1),lower than the Maximum Residue Limit(MRL)regulated by the European Union legislations(2007/19/EC)in foods,beverages,food packaging and toys(0.3-30 ng•mL^(−1)).This rapid and easy-to-use SPME-DART-FT-ICR-MS method provided a relatively high-throughput and powerful analytical approach for quick testing and screening phthalates in beverages and water samples to ensure food safety.

关键词： solid-phase micro-extraction direct analysis in real time Fourier transform ion cyclotron resonance mass spectrometry phthalates

Research on the Urban Agriculture Planning Models of Metropolis:A Case Study of Chengdu

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Journal of Landscape Research 2014年第5期6卷 22-25页

作者： QUE Yi wang haoyang School of Civil Engineering and Architecture Southwest Petroleum University

With the accelerating urbanization, ecological environment of the city has attracted increasing attention, so the resulting problems have become key research focuses in all countries. Against this background, urban agriculture has been applied as one of the effective approaches for relieving urbanization. From the perspective of industrial form of urban agriculture, planning models of urban agriculture were explored, industrial form and planning model of Chengdu urban agriculture were analyzed to forecast its development prospects. Multi-dimensional development, and sustainable development measures were given to guarantee the sustainable development of urban agriculture.

关键词： Urban agriculture Large city Planning model Sustainable development Chengdu

Analysis on Adaptability of Porous Asphalt Mixture to Heavy Duty Asphalt Pavements

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Analysis on Adaptability of Porous Asphalt Mixture to Heavy ...