Effectiveness of Ionic Polymer Soil Stabilizers on Warm Frozen Soil

Zhilong Zhang,Hu Zhang,Jianming Zhang,Mingtang Chai 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.7

Warm frozen soil has characteristics such as low shear strength and high compressibility. To improve its mechanical strength, the ionic polymer soil stabilizers (IPSS): named XRH stabilizer and acid cation exchange resin (CER) were adopted for reinforcing the warm frozen soil from the Beiluhe region of the Qinghai–Tibetan Plateau. To evaluate the effects of IPSS on warm frozen soil and analyze the mechanisms responsible, measurements were made of the physical, chemical and mechanical properties of warm frozen soil, both untreated and following treatment with IPSS. The addition of IPSS to the soil resulted in a significant decrease in the plasticity index, freezing temperature, and cation–exchange capacity of soil. The warm frozen soil were reinforced with XRH and CER, the cohesion increased by 87.9% and 43.1%, respectively, and the compressibility decreased by 44.5% and 41.1%, respectively. The trends of mechanical strength and unfrozen water content of reinforced warm frozen soil were the same, with extreme values being observed in response to treatment with an IPSS content of about 1% (optimal proportion). In addition, the curing mechanism of IPSS on warm frozen soil was analyzed. Overall, applying IPSS to the soil was an effective and feasible measure for reinforcing a warm frozen soil foundation.

Investigation on Air Texturing Process for Diacetate Blending with Polyester Filaments

Zhang, Jing,Zhang, Zhilong,Wang, Shanyuan,Qin, Xiaohong The Korean Fiber Society 2007 Fibers and polymers Vol.8 No.4

Influences of processing parameters on tensile property, stability and bulk of core-and-effect air textured yarns of diacetate polyester filaments are mainly examined in this paper. When the air pressure is raised, the tenacity and breaking elongation of textured yarns are reduced, Instability I and II tend to decrease at first and then increase, the core bulk declines markedly at first and then changes slowly, whereas the overall bulk changes little at first and then goes up greatly. With increase in texturing speed, the yarn tenacity and breaking elongation both drop initially then begin to increase, the core bulk and overall bulk are almost linearly increased, while the yarn instability changes with an unclear trend. When the winding underfeed ratio is increased, the yarn tenacity, breaking elongation and core bulk are reduced, but the yarn stability is slightly improved. The wetting of the core component produces higher tenacity, breaking elongation, instability and bulk, compared with that of the effect component or that of both, but the difference is insignificant.

Properties of Core-and-effect Air Textured Yarns Blended by Diacetate and Polyester Filaments

Zhang, Jing,Zhang, Zhilong,Wang, Shanyuan,Qing, Xiaohong The Korean Fiber Society 2007 Fibers and polymers Vol.8 No.1

In present work, PET FDY has been used to blend with diacetate filaments by air texturing process and core-and-effect air-textured yarns have been produced. The influences of both over-feeds of core and effect components on properties of textured yarns were mainly examined. It was observed that a spun-like effect of diacetate filaments occurred during air texturing and there were a little amount of free fiber ends besides loops on blended air textured yarns, while the number of free fiber ends changed little with variation in over-feeds. The tenacity of textured yarns decreased with increase in over-feeds of effect or core component. The breaking elongation increased with increase in over-feed of effect component, but decreased with increase in over-feed of core component. The yarn stability improves when both over-feeds are increased. The effect of over-feeds on boiling water shrinkage shows no clear trend. The core and average diameters are higher at high over-feed of effect component, but the over-feed of core component exhibits little effect on yarn diameters. The number and size of loops re increase with increased over-feed of effect component.

Analysis of Rock Mass Parameters and Plastic Zone of a Tunnel in Southwest Mountainous Area

Mengni Wang,Zhilong Zhang,Li Ren,Ru Zhang,Liangjuan Zheng,Lanbin Zhang,Zetian Zhang,Jing Xie,Xiaoling Liu 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.12

The deformation damage and support difficulties caused by the formation and expansion of plastic zone of surrounding rock have always been urgent engineering problems to be solved, especially in areas with prominent non-uniform stress fields. Choosing a reasonable and practical method to determine the plastic zone is of great significance for ensuring the long-term stability and safety of tunnels. Based on a tunnel project in the southwest mountainous area, this paper conducted mechanical tests to obtain the mechanical parameters of granite. The analytical method optimized based on the principle of stress balance was applied, and the numerical simulation was carried out according to the field displacement monitoring data and experimental parameters, the plastic zone of the medium quality granite cross-section and fault fracture zone granite cross-section was analyzed comprehensively. The results shown that the analytical and numerical solutions are in good agreement with engineering practice. It proved that the theory and method in this paper are scientific and practical in engineering. The research results can provide support for the design optimization and construction safety of the tunnel, and the research ideas and methods can also provide reference for similar projects.

RhoGDI2 induced malignant phenotypes of pancreatic cancer cells via regulating Snail expression

Yi Bin,Hu You,Zhu Dongming,Yao Jun,Zhou Jian,Zhang Yi,He Zhilong,Zhang Lifeng,Zhang Zixiang,Yang Jian,Tang Yuchen,Huang Yujie,Li Dechun,Liu Qiuhua 한국유전학회 2022 Genes & Genomics Vol.44 No.5

Background: Rho GDP dissociation inhibitor 2 (RhoGDI2) has been shown to contribute to the aggressive phenotypes of human cancers, such as tumor metastasis and chemoresistance. Objective: This study aimed to assess the effects of RhoGDI2 on tumor progression and chemoresistance in pancreatic cancer cells. Methods: The expression of RhoGDI2 in pancreatic cancer cells was detected by Western blot analysis. Gain-of-function and loss-of-function approaches were done to examine the malignant phenotypes of the RhoGDI2-expressing or RhoGDI2-depleting cells. The correlation between RhoGDI2 and Snail was also analyzed. Results: Differential expression of RhoGDI2 protein in pancreatic cancer cell lines was identified. Gain-of-function and loss-of-function experiments showed that RhoGDI2 induced the malignant phenotypes of pancreatic cancer cells, including proliferation, migration, invasion, and gemcitabine (GEM) chemoresistance. The upregulation of RhoGDI2 stimulated the expression of Snail, resulting in the altered expression of epithelial marker E-cadherin and mesenchymal marker Vimentin, which were characteristics of the tumorigenic activity of epithelial-mesenchymal transition. The expression of RhoGDI2 and Snail was upregulated in clinical tumor samples, and higher expression of RhoGDI2 or Snail was significantly associated with poor patient survival in pancreatic ductal adenocarcinoma (PDAC). Conclusion: The findings indicated that RhoGDI2 promoted GEM resistance and tumor progression in pancreatic cancer and that RhoGDI2 might be a potential therapeutic target in patients with PDAC.

Nonlinear dynamic analysis of cutting head-rotor-bearing system of the roadheader

Zhilong Huang,Zhongchao Zhang,Yiming Li,Guiqiu Song,Yang He 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.3

In order to study the dynamic characteristics of cutting head and cantilever system, a nonlinear dynamic model with a 13 degrees of freedom (13-DOF) lateral torsional coupled cutting head-rotor-bearing system (CHRBS) is established. The nonlinear coupled factors of spline clearance and bearing contact force are mainly considered, the dynamic analysis of CHRBS under time-varying load is carried out. The results show that there is no positive correlation between the cutting rock thickness and the states of chaotic motion and quasiperiodic motion. The system is in the two states mentioned above when in low speed region. With the increase of rotational speed, the chaotic motion becomes periodic motion. When the hardness of rock is lower, increasing rotational speed can reduce the vibration of the system, and the cutting thickness can be increased to improve the productivity and lump rock rate. As the hardness of rocks increases, the coupled system shows complex dynamic characteristics when the rotational speed changes from low to high, and the vibration increased. When cutting hard rock, the cutting speed should be increased. However, when the speed is too high, the cutting torque of system becomes smaller. In the case of cutting hard rock, reasonable rotational speed should be chosen between improving stability and increasing cutting force. The dynamic analysis results provide strong support for the vibration reduction and dynamic design of roadheader.

Online Safe Flight Envelope Protection for Icing Aircraft Based on Reachability Analysis

Zhilong Yu,Yinghui Li,Zhe Zhang,Wenfeng Xu,Zehong Dong 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.4

Icing encountered by an aircraft in flight can pose a great threat to flight safety, which is the foremost concern in aviation. Ice accretion has nonlinear and coupling properties, and therefore, a conventional envelope protection system cannot successfully deal with the condition. A safe flight envelope based on reachability analysis is proposed in this paper as a basis for designing an online envelope protection system for aircraft under icing conditions. This system uses a neural network method to identify changes in the aerodynamic coefficients and to classify the degrees of icing and uses a database-driven approach to solve the onboard safe flight envelope computation problem. The database of icing safe flight envelopes is created offline and can be retrieved in real time. The Research Civil Aircraft Model (RCAM) encountering icing conditions in the climbing phase was taken as an example to verify the feasibility of the online safe flight envelope protection system. The simulation results showed that the system can classify the degrees of icing efficiently, prevent the aircraft from deviating from the safe flight envelope, guide it back to the envelope along the fastest path, and reduce the risk of loss of control under icing conditions.

Properties of Wool/Spandex Core-Spun Yarn Produced on Modified Woolen Spinning Frame

Dang, Min,Zhang, Zhilong,Wang, Shanyuan The Korean Fiber Society 2006 Fibers and polymers Vol.7 No.4

Spandex has been successfully applied on modified worsted spinning system to produce spandex core spun yam. However it's difficult to produce wool/spandex core-spun yam on woolen spinning system with the same modified device because the drafting device of the two systems is quite different. A new method is introduced to apply spandex on woolen spinning system in this paper. Core-spun yam produced in this way has good appearance and quality by comparing with normal yam. A series of experiments were carried out to study the influence of spandex drafting ratio and yam twist factor on tensile' properties and elasticity of core-spun yams. The results indicate that core-spun yam with spandex drawing ratio of 2.5 and twist factor of 13.63 has highest value of tenacity and breaking elongation.

Neoadjuvant Chemotherapy-Guided Bladder-Sparing Treatment for Muscle-Invasive Bladder Cancer: Results of a Pilot Phase II Study

Hongzhe Shi,Wen Zhang,Xingang Bi,Dong Wang,Zejun Xiao,Youyan Guan,Kaopeng Guan,Jun Tian,Hongsong Bai,Linjun Hu,Chuanzhen Cao,Weixing Jiang,Zhilong Hu,Jin Zhang,Yan Chen,Shan Zheng,Xiaoli Feng,Changlin 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose Reduced quality of life after cystectomy has made bladder preservation a popular research topic for muscle-invasive bladder cancer (MIBC). Previous research has indicated significant tumor downstaging after neoadjuvant chemotherapy (NAC). However, maximal transurethral resection of bladder tumor (TURBT) was performed before NAC to define the pathology, impacting the real evaluation of NAC. This research aimed to assess real NAC efficacy without interference from TURBT and apply combined modality therapies guided by NAC efficacy. Materials and Methods Patients with cT2-4aN0M0 MIBC were confirmed by cystoscopic biopsy and imaging. NAC efficacy was assessed by imaging, urine cytology, and cystoscopy with multidisciplinary team discussion. Definite responders (≤ T1) underwent TURBT plus concurrent chemoradiotherapy. Incomplete responders underwent radical cystectomy or partial cystectomy if feasible. The primary endpoint was the bladder preservation rate. Results Fifty-nine patients were enrolled, and the median age was 63 years. Patients with cT3-4 accounted for 75%. The median number of NAC cycles was three. Definite responders were 52.5%. The complete response (CR) was 10.2%, and 59.3% of patients received bladder-sparing treatments. With a median follow-up of 44.6 months, the 3-year overall survival (OS) was 72.8%. Three-year OS and relapse-free survival were 88.4% and 60.0% in the bladder-sparing group but only 74.3% and 37.5% in the cystectomy group. The evaluations of preserved bladder function were satisfactory. Conclusion After stratifying MIBC patients by NAC efficacy, definite responders achieved a satisfactory bladder-sparing rate, prognosis, and bladder function. The CR rate reflected the real NAC efficacy for MIBC. This therapy is worth verifying through multicenter research.

Optimal Selection of Agricultural Products to Inhibit Citrinin Production during Submerged Culture of Monascus anka

Xu Xiong,Xuehong Zhang,Zhenqiang Wu,Zhilong Wang 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.6

Agricultural products exhibit a “buffering nature”during autoclaving and fermentation processes: i.e., thefinal pH of agricultural product medium after Monascusfermentation maintains a certain value. The protein contentof agricultural products strongly affects the bufferingcapacity and an extremely low final pH, below 3, can beachieved by the selection of agricultural products with lowprotein content, such as rice meal and cornmeal. This lowpH can be used to inhibit citrinin biosynthesis duringMonascus fermentation. Thus, optimal selection of agriculturalproducts with low protein content may provide a novelstrategy to inhibit citrinin production in submerged cultureof Monascus anka at a low initial pH for the production ofMonascus pigments. pH values ranging from 2.6 to 3 canbe maintained in Monascus fermentation using cornmeal/wheat starch (30:30 g/L) as substrate at initial pH 2.5,where the concentration of intracellular pigments reaches45 AU at 470 nm while citrinin is undetectable by TLCanalysis.