Structural and Thermal Characteristics of a High-Nitrogen Energetic Material: G(AHDNE)

Lu, Lei,Xu, Kangzhen,Zhang, Hang,Wang, Gang,Huang, Jie,Wang, Bozhou,Zhao, Fengqi Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.7

A high-nitrogen energetic salt, 1-amino-1-hydrazino-2,2-dinitroethylene guanidine salt [G(AHDNE)], was synthesized by reacting of 1-amino-1-hydrazino-2,2-dinitroethylene (AHDNE) and guanidine hydrochloride in sodium hydroxide aqueous solution. The theoretical investigation on G(AHDNE) was carried out by B3LYP/$6-311+G^*$ method. The thermal behaviors of G(AHDNE) were studied with DSC and TG-DTG methods, and the result presents an intense exothermic decomposition process. The enthalpy, apparent activation energy and pre-exponential constant of the process are $-1060J\;g^{-1}$, $148.7kJ\;mol^{-1}$ and $10^{15.90}s^{-1}$, respectively. The critical temperature of thermal explosion of G(AHDNE) is $152.63^{\circ}C$. The specific heat capacity of G(AHDNE) was studied with micro-DSC method and theoretical calculation method, and the molar heat capacity is $314.69J\;mol^{-1}K^{-1}$ at 298.15 K. Adiabatic time-to-explosion of G(AHDNE) was calculated to be a certain value between 60-72 s. The detonation velocity and detonation pressure were also estimated. G(AHDNE) presents good performances.

Experimental and Numerical Investigation of Axial Tensile Strength of CHS X-Joints Reinforced with External Stiffening Rings

Lei Zhao,Lei Zhu,Hailin Sun,Lu Yang,Xi Chen 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.3

To study the reinforcement eff ect of the external stiff ening ring reinforced and unreinforced X-joints having a circular hollow section subjected to brace tensile load, an experimental and computer-simulated research has been done. Six full-scale X-joints are examined in this study: three reinforced specimens and three corresponding unreinforced ones. The test specimens cover diff erent brace to chord diameters ratios ( β ) of 0.25, 0.51, and 0.73. The experimental facilities and detailed parameters are presented. The experimental results including failure modes, load–displacement curves, and ultimate capacity are analyzed and compared. Two failure modes, weld failure and chord plastifi cation, are observed in the tests. The test results reveal an ultimate load enhancement in the reinforced joints by approximately 50% in comparison with the unreinforced joints and an initial stiff ness increase of 248.1% for the β of 0.25 and approximately 49–76% for the β of 0.51 and 0.73. A fi nite element model using shell elements is developed, which accurately predicts the static performance of the X-joints subjected to brace tensile load with and without external stiff ening rings.

Experimental evaluation of an inertial mass damper and its analytical model for cable vibration mitigation

Lei Lu,Gaston A. Fermandois,Xilin Lu,Billie F. Spencer, Jr.,Yuan-Feng Duan,Ying Zhou 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.23 No.6

Cables are prone to vibration due to their low inherent damping characteristics. Recently, negative stiffness dampers have gained attentions, because of their promising energy dissipation ability. The viscous inertial mass damper (termed as VIMD hereinafter) can be viewed as one realization of the inerter. It is formed by paralleling an inertial mass part with a common energy dissipation element (e.g., viscous element) and able to provide pseudo-negative stiffness properties to flexible systems such as cables. A previous study examined the potential of IMD to enhance the damping of stay cables. Because there are already models for common energy dissipation elements, the key to establish a general model for IMD is to propose an analytical model of the rotary mass component. In this paper, the characteristics of the rotary mass and the proposed analytical model have been evaluated by the numerical and experimental tests. First, a series of harmonic tests are conducted to show the performance and properties of the IMD only having the rotary mass. Then, the mechanism of nonlinearities is analyzed, and an analytical model is introduced and validated by comparing with the experimental data. Finally, a real-time hybrid simulation test is conducted with a physical IMD specimen and cable numerical substructure under distributed sinusoidal excitation. The results show that the chosen model of the rotary mass part can provide better estimation on the damper’s performance, and it is better to use it to form a general analytical model of IMD. On the other hand, the simplified damper model is accurate for the preliminary simulation of the cable responses.

Two Maternal Lineages Revealed by Mitochondrial DNA D-loop Sequences in Chinese Native Water Buffaloes (Bubalus bubalis)

Lei, Chu-Zhao,Zhang, Wei,Chen, Hong,Lu, Fan,Ge, Qing-Lan,Liu, Ruo-Yu,Dang, Rui-Hua,Yao, Yun-Yi,Yao, Li-Bo,Lu, Zi-Fan,Zhao, Zhong-liang Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.4

Little is known about the origin and genetic diversity of swamp buffaloes in China. To obtain more knowledge on genetics of the water buffalo in China, the complete mitochondrial D-loop sequences of 30 samples from 6 native types were investigated. The results revealed 12 mitochondrial haplotypes with 50 polymorphic sites. Among these polymorphic sites, there were 49 transitions and 1 transversion. The average nucleotide diversity and haplotype diversity estimated from mtDNA D-loop region in 6 Chinese water buffalo types were 0.00684 and 0.798, respectively, showing rather abundant mitochondrial genetic diversity. The Neighbor-Joining (NJ) tree of mtDNA of Chinese water buffaloes was constructed according to the 12 haplotypes. The NJ tree indicated two lineages being designated lineage A and lineage B, in which lineage A was predominant, and lineage B was at low frequency. The new lineage B was first discovered and defined in 6 Chinese water buffalo types. These results showed that two different maternal lineages were involved in the origin of domestic swamp buffaloes in China and the lineage B was probably an introgression from Southeast Asian buffaloes.

Proposal of a Pretreatment Nomogram for Predicting Local Recurrence after Intensity-Modulated Radiation Therapy in T4 Nasopharyngeal Carcinoma: A Retrospective Review of 415 Chinese Patients

Lu-Lu Zhang,Yi-Yang Li,Jiang Hu,Guan-Qun Zhou,Lei Chen,Wen-Fei Li,Ai-Hua Lin,Jun Ma,Zhen-Yu Qi,Ying Sun 대한암학회 2018 Cancer Research and Treatment Vol.50 No.4

Purpose Local relapse-free survival (LRFS) differs widely among patients with T4 category nasopharyngeal carcinoma (NPC). We aimed to build a nomogram incorporating clinicopathological information to predict LRFS in T4 NPC after definitive intensity-modulated radiation therapy (IMRT). Materials and Methods Retrospective study of 415 Chinese patients with non-metastatic T4 NPC treated with definitive IMRT with or without chemotherapy at our cancer center between October 2009 and September 2013. The nomogram for LRFS at 3 and 5 years was generated based on multivariate Cox proportional hazards regression, and validated using bootstrap resampling, assessing discriminative performance using the concordance index (C-index) and determining calibration ability via calibration curves. Results Five-year LRFS was 88.8%. We identified and incorporated four independent prognostic factors for LRFS: ethmoid sinus invasion, primary gross tumor volume, age, and pretreatment body mass index. The C-index of the nomogram for local recurrence was 0.732 (95% confidence interval, 0.726 to 0.738), indicating excellent predictive accuracy. The calibration curve revealed excellent agreement between nomogram-predicted and observed LRFS probabilities. Risk subgroups based on total point score cutoff values enabled effective discrimination of LRFS. Conclusion This pretreatment nomogram enables clinicians to accurately predict LRFS in T4 NPC after definitive IMRT, and could help to facilitate personalized patient counselling and treatment strategies.

Iterative Generation Method of Arc Length Parameterized Curve Tool Path for Surface Machining from Short-Line Tool Path

Lei Lu,Jiang Han,Lian Xia,Cheng Fan,Haijun Liu,Shan Chen 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.10

To improve the application of the parametric curve tool path in surface machining, a method for generating arc-length parameterized toolpaths based on short-line toolpaths is proposed. The method first uses commercial CAM software to plan the short-line tool path. Then, the machining tool path with smooth continuous features is extracted. The smooth and continuous features are determined according to the chord length of the short-line tool path, and the extraction method is based on Chebyshev’s inequality of large numbers. After obtaining the smooth short-line trajectory, the iterative arc-length parameterized curve toolpath generation method is used to fit the discrete short-line toolpath. In the iterative process, the B-spline toolpath with parameterized chord length is obtained first. It is discretized according to the arc length difference information of the chord length B-spline. Finally, by continuously checking and inserting B-spline nodes, and fitting according to discrete points, the arc-length parameterized B-spline tool path is obtained. The feasibility of the method is verified with a part containing a sculpted surface, and two smooth arc-length parametric toolpaths are generated. In the end, the part is machined with the arc-length parameterized curve tool path.

Methyl jasmonate maintained higher esters content of ‘Nanguo’ pear on shelf life by regulating unsaturated fatty acid and reactive oxygen metabolisms

Lei Zhang,Lu-lu Zhang 한국원예학회 2024 Horticulture, Environment, and Biotechnology Vol.65 No.3

Cold storage is a widely employed technique for prolonging the post-harvest shelf life of ‘Nanguo’ pear. Nonetheless, this method has been observed to diminish the fruit’s aromatic properties. Given the signifi cance of aroma in determining the volatile quality, this research endeavors to examine the impact of methyl jasmonate (MeJA) in preserving aroma content, while also delving into the underlying molecular mechanisms that contribute to its effi cacy. Upon observing the metabolic changes, it was found that the pear, sprayed MeJA, could keep higher the content of aroma, ascorbic acid, polyphenol, oleic acid, linoleic acid, and linolenic acid than the control, but stearic acid and H 2 O 2 were decreased. The enzyme activities of lipoxygenase (LOX), alcohol acyl transferase (AAT), and catalase (CAT) were enhanced by MeJA treatment, but the polyphenol oxidase (PPO) was inhibited. Moreover, the gene expression levels of LOX , AAT , CAT , stearoyl-ACP desaturase ( SAD) , and fatty acid desaturase 2 ( FAD2) were promoted by MeJA. It is reasonable that sprayed MeJA was a reliable method for inhibiting aroma loss and triggered unsaturated fatty acid and reactive oxygen metabolisms.

Priority-based Differentiated Service in Spectrum Mobility Game

( Bingxian Lu ),( Zhenquan Qin ),( Lei Wang ),( Liang Sun ),( Ming Zhu ),( Lei Shu ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.4

In recent years, the problem of spectrum mobility in Cognitive Radio (CR) Networks has been widely investigated. In order to utilize spectrum resources completely, many spectrum handoff techniques based on game theory have been proposed, but most studies only concern that users how to achieve better payoffs, without much attention to the diverse needs of users. In this paper, we propose a new channel-switching model based on game theory, using a prioritized approach to meet the diverse needs of users in two different modes (CQ and PS). At the same time, this paper proposes some acceleration techniques to reach the Nash equilibrium more efficiently. We evaluate the performance of the proposed schemes depending on priority using real channel availability measurements, and conclude that the channel quality function (CQ) mode provide better service for priority user but the plan-sorting (PS) mode can be more suitable in multiple priority users exist scene.

ADDRESSING FOOD WASTE: AN EXPLORATION OF INGREDIENT SCHEMA INCONGRUITY OF UPCYCLED FOODS

Lei Li,Yalda Fadaeiresketi,Ernest Kwan,Irene R. R. Lu 글로벌지식마케팅경영학회 2023 Global Marketing Conference Vol.2023 No.07

Food waste is a critical problem for many countries. Food producers and groceries often discard imperfect foods or food by-products that still contain nutritional value. To address this problem, some food manufacturers have turned to upcycling, that is, to convert otherwise discarded ingredients into new food products (e.g., cacao fruit pulp into crunch bites). Consumers’ acceptance of sustainable products is generally lower than that of conventional products due to quality concerns. We speculate that for upcycled food products, consumers’ perception of product quality may vary when different percentages of imperfect ingredients are integrated into the products. Drawing from schema congruity theory, this research examines how the usage of imperfect ingredients can impact the perceived quality of upcycled food products. The implications for marketing upcycled foods are discussed.

GOLPH3, a Good Prognostic Indicator in Early-stage NSCLC Related to Tumor Angiogenesis

Lu, Ming,Tian, Yu,Yue, Wei-Ming,Li, Lin,Li, Shu-Hai,Qi, Lei,Hu, Wen-Si,Gao, Cun,Si, Li-Bo,Tian, Hui Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Background: Golgi phosphoprotein-3 (GOLPH3) is implicated in cancer development and progression. The aim of this study was to evaluate the prognostic significance of GOLPH3 protein and its association with tumor angiogenesis in patients with early-stage NSCLC. Materials and Methods: Immunohistochemistry was performed to determine GOLPH3 protein expression and allow assessment of intratumoral microvessel density (MVD) by counting CD-34 positive immunostained endothelial cells. Correlations of expression with MVD, clinicopathologic features and clinical prognosis were analyzed. Results: A notably higher level of GOLPH3 expression was found in early-stage NSCC tissues at the protein level. However, we do not find any correlation between GOLPH3 expression and clinicopathologic features (p>0.05), although higher MVD was positively associated with GOLPH3 overexpression (p<0.001). Expression of GOLPH3 was found to be an independent prognostic factor in early-stage NSCLC patients, those expressing high levels of GOLPH3 exhibiting a substantially lower 5-year overall survival than GOLPH3-negative patients (adjusted HR =1.899, 95% CI: 1.021-3.532, p=0.043). Conclusions: High expression of the GOLPH3 protein is common in early-stage NSCC, and is closely associated with tumor progression, increased tumor angiogenesis, and poor survival. We conclude a possibility of its use as a diagnostic and prognostic marker in early-stage NSCC patients.