Search

Your search keyword '"Zeng, Kuo"' showing total 341 results
Start Over Author "Zeng, Kuo"
341 results on '"Zeng, Kuo"'

103. Biomass pyrolysis mechanism for carbon-based high-value products.

Author

Liu, Juping, Chen, Xu, Chen, Wei, Xia, Mingwei, Chen, Yingquan, Chen, Hanping, Zeng, Kuo, and Yang, Haiping

Abstract

The utilization of biomass, the only carbon-bearing renewable energy source, is critical for environmental and energy sustainability as well as carbon neutrality. Pyrolysis is the efficient conversion of biomass to fuel gas, liquid oil, and solid char. It is necessary to understand the mechanism of biomass pyrolysis for valuable and efficient utilization. In this review, recent progress with respect to biomass pyrolysis properties, the pyrolysis process, and product upgrading strategies focusing on carbon-based high-value liquid fuels and carbon-bearing materials are summarized. First, the correlations between the pyrolysis behavior and biomass structure and process conditions are considered. The mechanisms of the biomass pyrolysis of hemicellulose, cellulose, and lignin as well as the potential effect of inorganic matter on biomass pyrolysis are discussed. Furthermore, the regulation and controlling strategies for the biomass pyrolysis of high-value products are outlined. Finally, the challenges and prospects are discussed in order to provide a comprehensive picture of biomass pyrolysis development, which is significant for the understanding of biomass pyrolysis and the development of biomass utilization technology. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

106. Molecular Characterization of Sub-Frontal Recurrent Medulloblastomas Reveals Potential Clinical Relevance

Author

Chen, Zirong, primary, Zhang, Xiaolin, additional, Liu, Guohao, additional, Peng, Peng, additional, He, Yue, additional, Wang, Jiajia, additional, Dong, Minhai, additional, Guo, Zhongyin, additional, Wan, Lijun, additional, Zeng, Kuo, additional, Xiang, Wang, additional, Yang, Huaitao, additional, Chen, Tao, additional, Long, Guoxian, additional, Xi, Qingsong, additional, Zhang, Bin, additional, and Wan, Feng, additional

Published
2022
Full Text
View/download PDF

116. Design of a Self-Management Solar Pyrolysis Packed-Bed Reactor by Coupling Thermal Energy Storage

Author

Zuo, Hongyang, Zeng, Kuo, zhong, Dian, Li, Jun, Xu, Huaqian, Lu, Yongwen, Lu, Wang, Zhou, Hongyu, Flamant, Gilles, Yang, Haiping, and Chen, Hanping

Abstract

A new packed-bed reactor coupled with thermal energy storage (TES) for solar pyrolysis of biomass is developed to overcome the shortcomings of solar energy. The numerical model of a 3.5 kW reactor is formulated by coupling heat and mass transfer balances to chemical kinetics for biomass pyrolysis. It is solved numerically by finite element techniques. The model is applied to analyze the influence of the storage component on the thermal and chemical performance of the pyrolysis process. A new criterion Ydefined as the ratio of the char yield and the effective solar power input is proposed to evaluate the effectiveness of solar power input. Under different solar radiation conditions, the coupled TES reduces the solar energy consumption for the char production by over 16%. The storage component can alleviate the overheating and thermal cyclic stresses on the absorption surface. As compared to the non-TES design, the new design can decrease the temperature fluctuation on the absorption surface for over 300 K during solar intermittencies. Moreover, the latent heat in the storage component makes the pyrolysis process stable. Under short-term interruptions, the variation of char yield in the terminal temperature range of 623–673 K is as large as 34.9% in the non-TES design, and it can be decreased to 16.5% after coupling TES. This value can also be decreased from 66.8% to 17.0% under long-term interruptions by coupling the storage.

Published
2023
Full Text
View/download PDF

119. Association Between Polymorphisms in the 5′ Region of the GALR1 Gene and Schizophrenia in the Northern Chinese Han Population: A Case–Control Study

Author

Li,Ya, Gao,Meng, Zeng,Kuo, Xing,Jia-xin, Xu,Feng-ling, Xuan,Jin-feng, Xia,Xi, Liu,Yong-ping, Yao,Jun, and Wang,Bao-jie

Subjects
Neuropsychiatric Disease and Treatment
Abstract

Ya Li, Meng Gao, Kuo Zeng, Jia-xin Xing, Feng-ling Xu, Jin-feng Xuan, Xi Xia, Yong-ping Liu, Jun Yao, Bao-jie Wang School of Forensic Medicine, China Medical University, Shenyang 110122, People’s Republic of ChinaCorrespondence: Bao-jie Wang; Jun Yao Email wangbj77@163.com; yaojun198717@163.comBackground: Epidemiological studies have shown that genetic factors are among the causes of schizophrenia. Galanin receptor 1 is an inhibitory receptor of galanin that is widely distributed in the central nervous system. This study mainly explored the relationship between polymorphisms of the 5′ region of the GALR1 gene and schizophrenia in the northern Chinese Han population.Methods: A 1545 bp fragment of the 5′ regulatory region of the GALR1 gene was amplified and sequenced in 289 schizophrenia patients and 347 healthy controls.Results: Among the haplotypes composed of the 16 detected SNPs, the haplotype H3 was identified as conferring a risk of schizophrenia (p=0.011, OR=1.430, 95% CI=1.084– 1.886). In addition, the haplotypes H4 and H7 were both protective against schizophrenia (p=0.024, OR=0.526, 95% CI=0.298– 0.927; p=0.037, OR=0.197, 95% CI=0.044– 0.885, respectively). In the subgroup analysis by sex, it was found that seven SNP alleles (rs72978691, rs11662010, rs11151014, rs11151015, rs13306374, rs5373, rs13306375) conferred a risk of schizophrenia in females (p< 0.05), while allele G of rs7242919 (p=0.007) was protective against schizophrenia in females. Moreover, the rs72978691 AA+AC genotype (p=0.006, OR=1.874, 95% CI=1.196– 2.937, power=0.780), rs7242919 CC+CG genotype (p=0.002, OR=2.027, 95% CI=1.292– 3.180, power=0.861), rs11151014 GG+GT genotype (p=0.008, OR=1.834, 95% CI=1.168– 2.879, power=0.735), rs11151015 GG+AG genotype (p=0.002, OR=2.013, 95% CI =1.291– 3.137, power=0.843), rs13306374 CC+AC genotype (p=0.006, OR=1.881, 95% CI=1.198– 2.953, power=0.788), and rs13306375 GG+AG genotype (p=0.006, OR=1.868, 95% CI=1.194– 2.921, power=0.770) increased the risk of schizophrenia in females. The haplotype FH2 consisting of rs72978691, rs11662010, rs7242919, rs11151014, rs11151015, rs13306374, rs5373, and rs13306375 may also be associated with the risk of schizophrenia in females (p=0.024).Conclusion: This study identified an association between polymorphisms in the 5′ region of the GALR1 gene and schizophrenia, especially in females.Keywords: galanin receptor 1, schizophrenia, single-nucleotide variant, genetic polymorphism, northern Chinese Han population

Published
2020

124. P-Based Additive for Reducing Fine Particulate Matter Emissions during Agricultural Biomass Combustion

Author

Zhu, Youjian, Fan, Jiyuan, Yang, Peng, Cheng, Wei, Zeng, Kuo, Zhang, Wennan, Yang, Haiping, Shao, Jingai, Wang, Xianhua, Chen, Hanping, Zhu, Youjian, Fan, Jiyuan, Yang, Peng, Cheng, Wei, Zeng, Kuo, Zhang, Wennan, Yang, Haiping, Shao, Jingai, Wang, Xianhua, and Chen, Hanping

Abstract

To understand the influence of P-containing compounds on particulate matter (PM) emissions from the combustion of agricultural residues, the combustion of cornstalk was performed with the addition of a phosphorus-based additive, namely, ammonium dihydrogen phosphate (NH4H2PO4), in a fixed-bed combustion system. Simultaneously the ash samples, including PM collected by a Dekati low-pressure impactor (DLPI) and residual ash, were analyzed with variant analytical techniques. It was found that NH4H2PO4 addition significantly reduced PM0.1 and PM0.1-1 yields but increased PM1-10 yields. The maximum PM0.1 and PM1 reduction efficiency can reach up to 50% at an optimal P/K molar ratio equal to 1. Meanwhile, the addition of NH4H2PO4 to cornstalk changed the chemical composition of PM1 from being dominated by KCl and KOH/K2CO3 with a small amount of K2SO4 to a system dominated by KPO3 and KCl with a small amount of K2SO4. Simultaneously, the possible PM1 reduction mechanism was proposed. In addition, the residual ash after combustion was rich in K- and P-containing species, indicating a potential utilization as a fertilizer. It showed that the addition of NH4H2PO4 is a promising approach to reduce PM1 emissions during the combustion of agricultural biomass.

Published
2019
Full Text
View/download PDF

129. Ash Fusion Characteristics and Transformation Behaviors during Bamboo Combustion in Comparison with Straw and Poplar

Author

Zhu, Youjian, Hu, Junhao, Yang, Wei, Zhang, Wennan, Zeng, Kuo, Yang, Haiping, Du, Shenglei, Chen, Hanping, Zhu, Youjian, Hu, Junhao, Yang, Wei, Zhang, Wennan, Zeng, Kuo, Yang, Haiping, Du, Shenglei, and Chen, Hanping

Abstract

In this work, the bamboo ash fusion and sintering characteristics were studied to evaluate its potential application in combustion for the production of heat and power. Poplar and wheat straw were used in the experimental test as the reference fuels for comparison. Standard ash fusion tests and ash sintering tests were carried out at elevated temperatures. The results indicate that bamboo has a low ash melting temperature of 862 °C, much lower than that of poplar. In spite of the high K content in bamboo ash, no severe melting and sintering was observed under the temperature lower than 1000 °C. The ashes after the tests were analyzed using SEM/EDX, XRF, and XRD techniques to illustrate the ash transformation behavior. Standard ash fusion tests indicated that the melting temperatures of bamboo, wheat straw, and poplar ashes are 862 °C, 770 °C, and 1088 °C, respectively. No severe sintering can be observed for poplar due to the large existence of refractory compounds. Ash sintering occurred when the temperature is higher than 800 °C, for wheat straw, due to the formation of the low melting temperature K-rich silicate. Additionally, bamboo ash has a relatively high P content compared to that of wheat straw, which facilitates the formation of high melting temperature compounds of K-Ca/Mg phosphates. Moreover, the ash content in bamboo is low. As a conclusion, bamboo is a good quality biofuel which can be fired in biomass combustion plants without severe sintering at a temperature lower than 1000 °C.

Published
2018
Full Text
View/download PDF

137. Solar pyrolysis of biomass at laboratory scale

Author

Zeng, Kuo and STAR, ABES

Subjects
Quantités de Produits, PCI des gaz, Solar energy, Beech wood, Modélisation, [SPI.OTHER] Engineering Sciences [physics]/Other, Pyrolyse, Modeling, Bois de Hêtre, Product yield, Energie Solaire, Gas LHV, Pyrolysis
Abstract

Concentrated solar energy provides heat to drive biomass pyrolysis reactions, which upgrades the feedstock energy by storing solar energy in chemical forms (bio-gas, bio-oil and bio-char). Thanks to high temperature and fast heating rate, more pyrolytic gas with high lower heating value (LHV) can be produced by direct solar pyrolysis. Experiments have highlighted the effect of solar pyrolysis parameters on products yields, composition and properties. The total gas LHV dramatically increases (5-fold) with increasing temperature (from 600°C to 1200°C) and sample heating rate (from 5°C/s to 50°C/s), which is mainly due to variations in the CO and H2 yields. The interaction between temperature and heating rate enhances at both high ranges. The maximum gas products LHV (14 589 kJ/kg of beech wood) was obtained at 2000°C and 450°C/s heating rate. The collected char and tar were analyzed and characterized, which emphasizes the temperature and heating rate effects. And the energy upgrade factor is determined as about 1.5 independent of temperature. At the same time, a 2D unsteady CFD particle model (simplified assumption using first-order Arrhenius type reactions) with heat and mass transfers was developed for solar pyrolysis. Numerical model predictions are in good agreement with experimental observations. Stoichiometric coefficients about the mass fraction of primary tar converted by the reaction to gas and secondary tar were determined at different temperatures and heating rates for the first time. The evolution of the final products and mass losses of biomass are enhanced with temperature and heating rate increase., L’énergie solaire concentrée est utilisée comme source de chaleur dans le but de mener des réactions de pyrolyse de la biomasse. Cela permet d’améliorer l’énergie contenue dans la matière première en stockant l’énergie solaire sous une forme chimique. Grâce à de hautes températures et à des vitesses de chauffe élevées, d’avantage de gaz pyrolytiques, avec un produit calorifique inférieur (PCI) élevé, peuvent être produit par la pyrolyse solaire directe.Les expériences effectuées dans ce travail montrent l’effet des paramètres de la pyrolyse solaire sur les quantités de produits, leur composition et leurs propriétés. Le PCI total des gaz augmente fortement (il est multiplié par 5) lorsque la température augmente (de 600°C à 1200°C), et lorsque la vitesse de chauffe augmente (de 5°C/s à 50°C/s. L’association de la température et de la vitesse de chauffe amplifie leurs effets lorsqu’ils sont tous deux à de hautes valeurs. Le charbon et le goudron collectés ont été analysés et caractérisés. Le facteur d’augmentation énergétique obtenu est d’environ 1.5 quelle que soit la température. Dans un second temps, un modèle non linéaire, en deux dimensions, et utilisant la CFD pour résoudre les bilans de masse et de chaleur, a été développé pour la pyrolyse solaire. Les coefficients stœchiométriques, déterminant la fraction massique du goudron primaire convertie par la réaction en gaz et en goudron secondaire, ont été déterminés à différentes températures et à différentes vitesses de chauffe. Les évolutions des produits finaux et des pertes de masse de la biomasse sont amplifiées par la température et par la vitesse de chauffe.

Published
2016

143. Parameter analysis and rapid design of porosity gradient distribution for open-cell metal foam in the latent thermal energy storage unit

Author

Kong, Jiayue, Zuo, Hongyang, Zeng, Kuo, Xu, Huaqian, Lu, Yongwen, Yang, Haiping, and Chen, Hanping

Abstract

The positive gradient porosity design of metal foam is used to improve the thermal performance of the vertical shell-and-tube latent thermal energy storage (LTES) unit. To optimize the gradient design, quantitative analysis is of vital importance. Therefore, the relative offset number EXis proposed in this study, which indicates the porosity difference between upper/down porosity and the mean porosity. Based on the numerical model of a shell-and-tube LTES unit filled with composite phase change material (CPCM) on the shell side, the effects of parameters, including the inlet HTF temperature and velocity, LTES dimensions, porosity, and thermal conductivity of the metal foam on the optimal gradient design are discussed. The optimal EXexhibits little relation with the inlet temperature but increases with the LTES height and thermal conductivity, while decreases with inlet velocity, porosity, and LTES outer radius. With the correlation between the optimal EXand the relative dimensionless number, the effects of these parameters on the optimal EXare integrated and quantified as experience equations so that the optimal porosity gradient of metal foam and the relative reduction melting time can be rapidly obtained under a wide variety of practical applications.

Published
2024
Full Text
View/download PDF

144. Melting enhancement in a shell-and-tube latent heat storage unit with staggered fin-foam synergistic configuration

Author

Lu, Yongwen, Wu, Mingyang, Zuo, Hongyang, Xu, Huaqian, Zeng, Kuo, Chi, Bowen, Gao, Junjie, Fang, Zheyu, Yang, Haiping, and Chen, Hanping

Abstract

Latent heat thermal energy storage has been demonstrated as a promising energy storage technique in concentrating solar power plants, but the application of that is restricted by low storage efficiency. To address this issue, an innovative design of staggered fin-foam synergistic configuration is proposed in the current study. A three-dimensional shell-and-tube model is built to numerically investigate the effect of the new design on melting enhancement. Compared with foam unilateral configuration, straight fin-foam synergistic configuration reduces the full melting time by 58.67 %. By adopting the segmented staggered configuration and increasing the number of segments, performance is further improved. Optimal segmented staggered fin-foam configuration with four segments performs best and further reduces the full melting time by 13.18 %. Staggered fin-foam synergistic enhancement breaks the limitation of marginal improvements in unilateral enhancement and enables underutilized heat in the sector between adjacent fins to be further conducted. The outlet temperature of heat transfer fluid is further reduced by 23.55 K, achieving more efficient heat utilization. A comprehensive economic index is developed for economic assessment. The fin-foam configuration exhibits better economic benefits compared to the foam unilateral configuration. The stagger fin-foam configuration emerges as the optimal choice with a relatively low cost of processing and pumping power.

Published
2024
Full Text
View/download PDF

146. Improving the staged gasification of crop straw by choosing a suitable devolatilization temperature.

Author

Yi, Wei, Wang, Xianhua, Zeng, Kuo, Yang, Haiping, Shao, Jingai, Zhang, Shihong, and Chen, Hanping

Subjects
CORNSTALKS, BIOMASS gasification, STRAW, CROPS, HIGH temperatures
Abstract

A novel biomass staged gasification technology is under development, which includes a medium temperature devolatilization (MTD) stage and a high temperature gasification stage. In this study, the MTD of corn stalk with high K content was conducted at a wide temperature range of 200–550 °C, and the obtained biochar was subjected to steam gasification at 900 °C. The distribution and characteristics of the products from both stages were analyzed in detail. The results demonstrate that owing to the moderate reduction of O/C and the enrichment of fixed carbon and K, a devolatilization temperature exceeding 300 °C, especially at 450 °C, showed a significant promotion effect on the gasification performance. The syngas production, H 2 production and H 2 /CO ratio increased from 62.23 mmol/g, 33.59 mmol/g and 2.13 for corn stalk to 106.15 mmol/g, 72.09 mmol/g and 3.38 for biochar obtained at 450 °C, respectively. This study revealed the correlation between different physicochemical characteristics and gasification performances of MTD-char and the internal mechanism, which is conducive to the high-value utilization of low-quality biomass (i.e., crop straw) via staged gasification. [Display omitted] • Deoxidation on benzene ring will inhibit the gasification reactivity of biochar. • Devolatilization at 350–550 °C significantly increased the K content in corn stalk. • O/C of MTD-char can be used to predict the syngas quality after its gasification. • K and FC content jointly determine gasification reaction intensity of MTD-char. • 300–550 °C is the suitable MTD temperature range for corn stalk staged gasification. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

148. Investigation of optimization methods for metal foam with two-dimensional porosity gradient in shell-and-tube latent heat storage

Author

Kong, Jiayue, Zuo, Hongyang, Zeng, Kuo, Lu, Yongwen, Xu, Huaqian, Zhang, Xiong, Yang, Haiping, and Chen, Hanping

Abstract

The latent heat thermal energy storage (LTES) strengthened by metal foam can promote the development of renewable energy and waste heat recovery. In this study, superposition method and 2D iterative method are established to optimize the 2D porosity gradient of metal foam, which is infiltrated in phase change material (PCM) for heat transfer enhancement in LTES with shell-and-tube configuration. The optimization process in these new methods takes the interaction between horizontal and vertical porosity gradient into account and the evolution of two-dimensional metal foam porosity is numerically investigated. Melting behaviors of optimal cases with different methods are compared and analyzed. The numerical results demonstrated that the optimal case obtained by 2D iterative method has best heat transfer performance. Compared with the uniform distribution, a 11.32 % reduction in full melting time can be achieved by the 2D iterative optimal case due to its better temperature uniformity and stronger natural convection.

Published
2023
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results