Effects of cellulose, hemicellulose and lignin on biomass pyrolysis kinetics

Lingli Zhu,Zhaoping Zhong 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.10

In order to investigate interactions among biomass components on pyrolysis kinetics, pyrolysis experiments of individual components, synthetic biomass (designed by Design-Export software) and natural biomass (rice husk and corn straw) were conducted on a thermogravimetric analyzer (TGA). The results revealed that the pyrolysis behavior of cellulose is sharp, which is with low pyrolysis reaction order (1.38), high activation energy (168.61 kJ/mol) and high pre-exponential factor (3.50E+12 /s). The pyrolysis behavior of hemicellulose and lignin is slower but more complicated, both with high pyrolysis reaction order (2.30, 1.51), low activation energy (126.31, 87.21 kJ/mol), and low pre-exponential factor (9.67E+09, 2.59E+05 /s). Comparison of the experimental and calculated kinetics of synthetic samples confirmed that interactive effects on pyrolysis kinetics exist in the co-pyrolysis process. In particular, the presence of lignin inhibited the pyrolysis reaction rate of synthetic biomass, and cellulose played the dominant role in the activation energy and frequency factor. The pyrolysis reaction order was strongly influenced by hemicellulose owing to its abundant and complex branched chains. The predicted model was also established for calculating kinetic parameters of natural biomass with known proportions of three components. The predicted results were consistent with the experimental ones, validating the effectiveness of the prediction model.

Printing performance of 3D printing cement-based materials containing steel slag

Zhu, Lingli,Yang, Zhang,Zhao, Yu,Wu, Xikai,Guan, Xuemao Techno-Press 2022 Advances in concrete construction Vol.13 No.4

3D printing cement-based materials (3DPCBM) is an innovative rapid prototyping technology for construction materials. This study is tested on the rheological behavior, printability and buildability of steel slag (SS) content based on the extrusion system of 3D printing. 0, 8 wt%, 16 wt%, 24 wt%, 32 wt% and 40 wt% SS was replaced cement, The test results revealed that the addition of SS would increase the fluidity of the printed paste, prolong the open time and setting time, reduce the plastic viscosity, dynamic yield stress and thixotropy, and is beneficial to improve the pumping and extrudability of 3DPCBM. With the increase of SS content, the static yield stress developed slowly with time which indicated that SS is harmful to the buildability of printing paste. The content of SS in 3DPCBM can reach up to 40% at most under the condition of satisfying rheological property and buildability, it provides a reference for the subsequent introduction of SS and other industrial solid waste into 3DPCBM by explored the influence law of SS on the rheological properties of 3DPCBM.

Ultrastructure of Pear Pollen Tubes Challenged with Stylar S-RNase in Vitro

Zhu Qin Liu,Shao Ling Zhang,Guo Hua Xu,Cai Ping Zhao,Jun Wu 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Potential Mechanisms of Benzyl Isothiocyanate Suppression of Invasion and Angiogenesis by the U87MG Human Glioma Cell Line

Zhu, Yu,Zhang, Ling,Zhang, Guo-Dong,Wang, Hong-Ou,Liu, Ming-Yan,Jiang, Yuan,Qi, Li-Sha,Li, Qi,Yang, Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Glioma is one of the most common tumors in China and chemotherapy is critical for its treatment. Recent studies showed that benzyl isothiocyanate (BITC) could inhibit the growth of glioma cells, but the mechanisms are not fully understood. This study explored the inhibitory effect of BITC on invasion and angiogenesis of U87MG human glioma cells in vitro and in vivo, as well as potential mechanisms. It was found that BITC could inhibit invasion and angiogenesis of human glioma U87MG cells by inducing cell cycle arrest at phase G2/M. It also was demonstrated that BITC decreased expression of cyclin B1, p21, MMP-2/9, VE-cadherin, CD44, CXCR4 and MTH1, the activity of the telomerase and $PKC{\zeta}$ pathway. Microarray analysis was thus useful to explore the potential target genes related to tumorigenic processes. BITC may play important roles in the inhibition of invasion and angiogenesis of human glioma cells.

SYNTHESIS AND FLUORESCENCE PROPERTIES OF LaF 3 :Tb 3 þ PHOSPHORS VIA ULTRASONIC- ASSISTED IONIC LIQUID METHOD

LING ZHU,XUEQIANG CAO,SANXI LIU,YU HUI,BINGLIN ZOU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.7

Hexagonal phase LaF 3 :Tb 3 þnano/microcrystals were successfully synthesized via ultrasonic-assisted ionic liquid (IL) method. The ¯eld emission scanning electron microscope (FESEM)images revealed that the morphologies of the as-prepared LaF 3 :Tb 3 þsamples were graduallyconverted from nanoplates to microcylinders with increasing the concentration of Tb 3 þions. Thephotoluminescent (PL) spectrum shows that all the as-prepared La 1 ?xTbxF 3 samples show thecharacteristic emissions of Tb 3 þ 5D4 ! 7FJ (J ¼ 6-3, with 5D4 ! 7F5 green emission at 542 nmas the strongest one) transitions. The optimal Tb 3 þ-doped concentration is 20 mol.% in the LaF 3host. The photoluminescence intensity of the La 0 : 80 Tb 0 : 20 F 3 microcylinders prepared by ultra-sonic irradiation was largely improved as compared with that of the product prepared by stirring.

Performance and Design of Shear Connectors in Composite Beams with Parallel Profiled Sheeting at Elevated Temperatures

Ling-Zhu Chen,Gianluca Ranzi,Shou-Chao Jiang,Faham Tahmasebinia,Guo-Qiang Li 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.1

This paper describes an extensive experimental and numerical study conducted to evaluate the thermo-structural response of shear connectors embedded in composite slabs with steel sheeting parallel to the steel beam, with particular focus on opentrapezoidal profiles. For this purpose, eight push-out tests were carried out at different levels of temperature. A threedimensional finite element model was developed in Abaqus and its accuracy was validated against the experimental measurements collected as part of this study. The model was then used to perform a parametric study to gain insight into the structural response at different temperatures. The experimental and numerical results were then used to evaluate the accuracy of available European guidelines for predicting the capacity of shear connectors at elevated temperatures (when embedded in composite slabs with the profiled sheeting parallel to the steel beam). Finally, a new design equation was proposed to calculate the degradation factor defining the resistance of shear connectors for different levels of temperature

Ultrastructural observations on spermiogenesis in the peanut worm, Phascolosoma esculenta (Sipuncula: Phascolosomatidea)

Lingli Long,Zhang Sheng,Junquan Zhu 한국통합생물학회 2015 Animal cells and systems Vol.19 No.3

Ultrastructural characteristics of spermiogenesis in the peanut worm, Phascolosoma esculenta (Phascolosomatidea), were observed by transmission electron microscopy (TEM). The spermiogenesis principally occurs in the coelom and can be divided into three stages (the early, middle and late stages) based on the chromatin morphology, acrosome development, spermatozoon midpiece and flagellum formation. Spermatids within a given spermatid mass develop synchronously. With the spermiogenesis proceeding, the spermatid masses become loosely structured, and later, adjacent spermatids are interconnected at one extremity of the cells. Gradually, condensation of the chromatin accelerates and is almost completed in late spermiogenesis, leaving the late spermatids with highly condensed homogeneous chromatin. In the spermatid head, the conical acrosome is generally composed of an acrosomal vesicle which is formed by the coalescence of small proacrosomal vesicles within the cytoplasm, a subacrosomal space that situates between the acrosomal vesicle and nucleus, and an acrosomal rod which develops from a bunch of filamentous material within the subacrosomal space. Certain mitochondria move posteriorly towards the nucleus, thus constituting the spermatozoon midpiece. The flagellum, originated from the distal centriole, appears in the early spermiogenesis. Ultimately, mature spermatidium dissociates into numerous spermatozoa, which are subsequently released as a single cell from the coelom into the nephridia. The spermatozoon has a prominent head, containing an acrosome and nucleus, a short midpiece and a slender tail. When compared with other sipunculans or invertebrates with external fertilization, the spermiogenesis of P. esculenta, presumably, is closely associated with its biological adaptations for the reproductive strategy.

Preparation, characterization and catalytic performance of HPW-TUD-1 catalyst on oxidative desulfurization

Ling Tang,Lihua Kang,Mingyuan Zhu,Guangqin Luo,Bin Dai 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.2

By incorporating H3PW12O40 (HPW) heteropolyacid into mesoporous TUD-1 materials, a series of HPWTUD-1 catalysts were synthesized. Nitrogen adsorption–desorption isotherm, XRD and FTIR characterizations showed that these catalyst exhibited mesoporous structure, and HPW presented in the catalysts with Keggin structure. The catalytic performances of the HPW-TUD-1 catalysts were tested through the oxidative desulfurization (ODS) process of dibenzothiophene (DBT) model oil. The results showed that the obtained 20HPW-TUD-1 catalyst displayed excellent catalytic activity and recover ability for ODS. The desulfurization rate of DBT reached up to 98.1%, and almost no catalytic activity loss was observed after three recycles of the catalyst.

Damage identification of vehicle-track coupling system from dynamic responses of moving vehicles

Zhu, Hong-Ping,Ye, Ling,Weng, Shun,Tian, Wei Techno-Press 2018 Smart Structures and Systems, An International Jou Vol.21 No.5

The structural responses are often used to identify the structural local damages. However, it is usually difficult to gain the responses of the track, as the sensors cannot be installed on the track directly. The vehicles running on a track excite track vibration and can also serve as response receivers because the vehicle dynamic response contains the vibration information of the track. A damage identification method using the vehicle responses and sensitivity analysis is proposed for the vehicle-track coupling system in this paper. Different from most damage identification methods of vehicle-track coupling system, which require the structural responses, only the vehicle responses are required in the proposed method. The local damages are identified by a sensitivity-based model updating process. In the vehicle-track coupling system, the track is modeled as a discrete point supported Euler-Bernoulli beam, and two vehicle models are proposed to investigate the accuracy and efficiency of damage identification. The measured track irregularity is considered in the calculation of vehicle dynamic responses. The measurement noises are also considered to study their effects to the damage identification results. The identified results demonstrate that the proposed method is capable to identify the local damages of the track accurately in different noise levels with only the vehicle responses.

Structural damage and force identification under moving load

Zhu, Hongping,Mao, Ling,Weng, Shun,Xia, Yong Techno-Press 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.2

Structural damage and moving load identification are the two aspects of structural system identification. However, they universally coexist in the damaged structures subject to unknown moving load. This paper proposed a dynamic response sensitivity-based model updating method to simultaneously identify the structural damage and moving force. The moving force which is equivalent as the nodal force of the structure can be expressed as a series of orthogonal polynomial. Based on the system Markov parameters by the state space method, the dynamic response and the dynamic response derivatives with respect to the force parameters and elemental variations are analytically derived. Afterwards, the damage and force parameters are obtained by minimizing the difference between measured and analytical response in the sensitivity-based updating procedure. A numerical example for a simply supported beam under the moving load is employed to verify the accuracy of the proposed method.