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EXTERNAL BODY FORCEIN FINITE DIFFERENCE LATTICE BOLTZMANN METHOD

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Journal of Hydrodynamics 2005年第4期17卷 473-477页

作者： CHEN Sheng LIU Zhao-hui SHI Bao-chang ZHENG chu-guang State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China

A new finite difference lattice Boltzmann scheme is developed. Because of analyzing the influence of external body force roundly, the correct Navier-Stokes equations with the external body force are recovered, without any additional unphysical terms. And some numerical results are presented. The result which close agreement with analytical data shows the good performance of the model.

关键词： Finite Difference Lattice Boltzmann Method (FDLBM) body force

A FEM-DFN model for the interaction and propagation of multi-cluster fractures during variable fluid-viscosity injection in layered shale oil reservoir

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Petroleum Science 2022年第6期19卷 2796-2809页

作者： chu-Hao Huang Hai-Yan Zhu Jian-Dong Wang Jian Han guang-Qing Zhou Xuan-He Tang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanPR China Petroleum Engineering Technology Research Institute Shengli Oilfield CompanySINIOPECDongying257000ShandongPR China Chongqing Gas Field Southwest Oil and Gas Field CompanyPetro ChinaChongqing400021PR China

To investigate the height growth of multi-cluster fractures during variable fluid-viscosity fracturing in a layered shale oil reservoir,a two-dimensional finite element method(FEM)-discrete fracture network(DFN)model coupled with flow,stress and damage is proposed.A traction-separation law is used to describe the mixed-mode response of the damaged adhesive fractures,and the cubic law is used to describe the fluid flow within the *** rock deformation is controlled by the in-situ stress,fracture cohesion and fluid pressure on the hydraulic fracture *** coupled finite element equations are solved by the explicit time difference *** effects of the fracturing treatment parameters including fluid viscosity,pumping rate and cluster spacing on the geometries of multifractures are *** results show that variable fluid-viscosity injection can improve the complexity of the fracture network and height of the main fractures *** pumping rate of15 m^(3)/min,variable fluid-viscosity of 3-9-21-36-45 mPa s with a cluster spacing of 7.5 m is the ideal treatment *** field application shows that the peak daily production of the application well with the optimized injection procedu re of variable fluid-viscosity fracturing is 171 tons(about 2.85 times that of the adjacent well),which is the highest daily production record of a single shale oil well in China,marking a strategic breakthrough of commercial shale oil production in the Jiyang Depression,Shengli *** variable fluid-viscosity fracturing technique is proved to be very effective for improving shale oil production.

关键词： Shale oil reservoir FEM-DFN model Fracture propagation Variable fluid-viscosity injection Bedding planes

Low-temperature heat transport of the zigzag spin-chain compound SrEr_(2)O_(4)

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Chinese Physics B 2022年第8期31卷 621-626页

作者： Liguo chu Shuangkui guang Haidong Zhou Hong Zhu Xuefeng Sun Department of Physics Key Laboratory of Strongly-Coupled Quantum Matter Physics(CAS)University of Science and Technology of ChinaHefei 230026China Department of Physics and Astronomy University of TennesseeKnoxvilleTennessee 37996-1200USA Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

Low-temperature thermal conductivity(κ),as well as the magnetic properties and specific heat,are studied for the frustrated zigzag spin-chain material Sr Er_(2)O_(4)by using single-crystal *** specific heat data indicate the longrange antiferromagnetic transition at~0.73 K and the existence of strong magnetic *** magnetizations at very low temperatures for magnetic field along the c axis(spin chain direction)or the a axis reveal the field-induced magnetic ***κshows a strong dependence on magnetic field,applied along the c axis or the a axis,which is closely related to the magnetic ***,high magnetic field induces a strong increase ofκ.These results indicate that thermal conductivity along either the c axis or the a axis are mainly contributed by phonons,while magnetic excitations play a role of scattering phonons.

关键词： spin chain quantum spin system thermal conductivity

Soil Nitrogen Distribution and Plant Nitrogen Utilization in Direct-Seeded Rice in Response to Deep Placement of Basal Fertilizer-Nitrogen

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Rice science 2019年第6期26卷 404-415页

作者： WANG Danying YE Chang XU chunmei WANG Zaiman CHEN Song chu guang ZHANG Xiufu State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 China Key Laboratory of Key Technology on Agricultural Machine and Equipment Ministry of Education / South China Agricultural University Guangzhou 510642 China

Deep placement of controlled-release fertilizer increases nitrogen (N) use efficiency in rice planting but is expensive. Few studies on direct-seeded rice have examined the effects of deep placement of conventional fertilizer. With prilled urea serving as N fertilizer, a two-year field experiment with two N rates (120 and 195 kg/hm2) and four basal N application treatments (B50, all fertilizer was broadcast with 50% as basal N;D50, D70 and D100 corresponded to 50%, 70% and 100% of N deeply placed as basal N, respectively) were conducted in direct-seeded rice in 2013 and 2014. Soil N distribution and plant N uptake were analyzed. The results showed that deep placement of basal N significantly increased total N concentrations in soil. Significantly greater soil N concentrations were observed in D100 compared with B50 at 0, 6 and 12 cm (lateral distance) from the fertilizer application point both at mid-tillering and heading stages. D100 presented the highest values of dry matter and N accumulation from seeding to mid-tillering stages, but it presented the lowest values from heading to maturity stages and the lowest grain yield for no sufficient N supply at the reproductive stage. The grain yield of D50 was the highest, however, no significant difference was observed in grain yield, N agronomic efficiency or N recovery efficiency between D70 and D50, or between D70 and B50, while D70 was more labor saving than D50 for only one topdressing was applied in D70 compared with twice in other treatments. The above results indicated that 70% of fertilizer-N deeply placed as a basal fertilizer and 30% of fertilizer-N topdressed as a panicle fertilizer constituted an ideal approach for direct-seeded rice. This recommendation was further verified through on-farm demonstration experiments in 2015, in which D70 produced in similar grain yields as B50 did.

关键词： direct-seeded rice nitrogen fertilizer deep placement soil nitrogen distribution nitrogen utilization

A pilot study of intraocular lens explantation in 69 eyes in Chinese patients

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International Journal of Ophthalmology(English edition) 2017年第4期10卷 579-585页

作者： Fang Chai Bo Ma Xin-guang Yang Juan Li Mei-Fang chu Xi’an No.4 Hospital Shaanxi Ophthalmic Medical CenterAffiliated Guangren HospitalSchool of MedicineXi'an Jiaotong University

AIM：To study the effects of intraocular lens（IOL） explantation and demographic ***：Retrospective non-comparative case *** data recorded from patient charts included the following：demographic,preoperative and postoperative characteristics;complications;surgical methods,and changes in visual ***：A total of 69 eyes in 67 Chinese patients who received IOL explants were *** patients＇ mean age at the time of explantation was 46.1 years old [SD 22.5（6-85）],and 37 patients were female（55.2%）.Regarding employment,47.8% were farmers,23.9% were retired,16.4% were students,4.5% were unemployed,3% were workers,and 4.5% were other（including staff members,teachers and officers）.The main reasons for explantation were dislocation/decentration in 41 cases（59.4%） and retinal detachment in 10 cases（14.5%）.The third most prevalent cause was incorrect lens power in 7 eyes（10.1%）.The remaining reasons were endophthalmitis in 6 cases（8.7%）,posterior capsular opacity in 3 eyes（4.3%）,and impacting retinal surgery operation in 2 cases（2.9%）.The main comorbidities were high myopia in 18 eyes（26.1%）,trauma in 8 eyes（11.6%）,retinal detachment in 6 eyes（8.7%）,congenital cataracts in 8 eyes（11.6%）,and Marfan＇s syndrome in 2 eyes（2.9%）.The mean time from implantation to explantation was 4.0y [SD 4.2（0.005-15）].Treatment after explantation included posterior chamber IOL implantation in 44 eyes（63.8%） and aphakia in 25 eyes（36.2%）.After surgery,the best corrected visual ability（BCVA） was improved in 50 cases（72.5%）,including 28 patients（40.6%） in whom visual ability was improved by more than two ***：Dislocation/decentration is the main cause for explantation,and high myopia is a main risk *** chamber IOL implantation remains the most elected treatment after explantation.

关键词： explantation intraocular lens dislocation

Investigation of Absorption of Nanocrystalline Silicon

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Chinese Physics Letters 1999年第11期16卷 833-835页

作者： MA Zhi-xun LIAO Xian-bo KONG guang-lin chu Jun-hao State Key Laboratory for Surface Physics Institute of SemiconductorsCenter for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100083 National Laboratory for Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083

Nanocrystalline silicon embedded SiO2 matrix is formed by annealing the SiOx films fabricated by plasma enhanced chemical vapor deposition technique. In conjunction with the micro-Raman spectra, the absorption spectra of the films have been investigated. The blue-shift of absorption edge with decreasing size of silicon crystallites is due to quantum confinement effect. It is found that nanocrystalline silicon is of an indirect band structure, and that the absorption presents an exponential dependence of absorption coefficient on photon energy in the range of 2.0-3.0eV, and a sub-band appears in the range of 1.0-1.5eV. We believe that the exponential absorption is due to the indirect band-to-band transition of electrons in silicon nanocrystallites, while the sub-band absorption is ascribed to transitions between the amorphous silicon states existing in the films.

关键词： technique. absorption exponential

Ureteroscopic holmium laser to transect the greater omentum to remove an abdominal drain:Four case reports

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World Journal of Clinical Cases 2021年第31期9卷 9584-9591页

作者： Hong-Ming Liu guang-Heng Luo Xiao-Fei Yang Zhu-Gang chu Tian Ye Zhi-yong Su Li Kai Xiu-Shu Yang Zhen Wang Department of Urology Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina Department of Urology The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina Department of General Surgery Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina

BACKGROUND Drainage tube removal is difficult when the greater omentum becomes incarcerated in the drainage tube through the side ***,known removal methods are either ineffective or will cause additional damage to the patient in a secondary *** and the holmium laser have been used in various surgical techniques in urology,and in theory,they are expected to be a good strategy for solving the problem of tissue *** SUMMARY Four patients diagnosed with difficult removal of an abdominal drainage tube following abdominal surgery are *** patients underwent surgery to remove the incarcerated greater omentum in the drainage tube using a holmium laser and a ureteroscope,and a new 16-F drain was then placed in the abdominal or pelvic *** efficacy of this technique was evaluated by intraoperative conditions,success rate,and operating time;safety was evaluated by perioperative conditions and the probability of postoperative *** four operations went smoothly,and the drains were successfully removed in all *** average operating time was 24.5 ***,the average irrigation volume was 892.0 mL,the average drainage volume was 638.5 mL,and no bleeding or damage to surrounding tissues was ***,the average drainage volume was 32.8 mL and the new drains were removed within 36 *** patients were able to get out of bed and move around within 12 *** visual analogue pain scores were all below *** average follow-up duration was 12.5 mo and no complications such as fever or bleeding were *** Ureteroscopic holmium laser surgery is an effective,safe and minimally invasive technique for removing drains where the greater omentum is incarcerated in the abdominal drain.

关键词： Ureteroscope Holmium laser Drainage Greater omentum Complication of abdominal surgery Case report

陶渊明《归去来兮辞》是“文”吗?——兼论“辞”的文体特点

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北京社会科学 2024年第5期 34-43页

作者：李定广丁震寰上海师范大学人文学院

陶渊明《归去来兮辞》,高中《语文》课本定为“文”,而当代研究著作及诗文选本中,或被归为“诗”,或被归为“文”,使得《归去来兮辞》文体归属成了疑难问题。经考察,《归去来兮辞》在宋前被归于“辞”或“诗”无异议,宋代开始有人将其... 详细信息

陶渊明《归去来兮辞》,高中《语文》课本定为“文”,而当代研究著作及诗文选本中,或被归为“诗”,或被归为“文”,使得《归去来兮辞》文体归属成了疑难问题。经考察,《归去来兮辞》在宋前被归于“辞”或“诗”无异议,宋代开始有人将其视作“文”。“辞”作为文体概念时有两重含义,其一指“楚辞体”的诗,与“骚”实为一体异名,这一文体常与“赋”发生混淆。较之于“赋”,在文体形式上“辞”在句中或句末多带有“兮”字或其他语气助词;在文体属性上“辞”更多的是直接自我抒情,与“赋”以铺陈体物为主有别;文体写作上“辞”的感情流动是作品内部生发的,即所谓“潜气内转”,“赋”则多靠使用关联词连接意脉。其二指歌词,这一文体概念后来被“词”包含。《归去来兮辞》完全符合“辞”的文体特点,本质属性是诗,在当下文体分类中应该归于诗而非文。

关键词：《归去来兮辞》辞文体归属辞赋差异

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Influence of zinc on electrochemical discharge activity of Mg-6%Al-5%Pb anode

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Journal of Central South University 2012年第1期19卷 9-16页

作者： WANG Nai-guang WANG Ri-chu PENG Chao-qun FENG Yan Science and Engineering Central South UniversityChangsha 410083China

Mg-6%Al-5%Pb(mass fraction) anodes with different contents of zinc were prepared by melting and *** electrochemical discharge behavior of these anodes in 3.5% NaCl solutions was investigated by galvanostatic test and electrochemical impedance spectroscopy(EIS).The microstructures and the corroded surfaces of these anodes were studied by scanning electron microscopy(SEM) and emission spectrum analysis(ESA).The phase structures and the corrosion products of the anodes were analyzed by X-ray diffraction(XRD).The results show that zinc promotes the grain refinement of Mg-6%Al-5%Pb anode and makes the average discharge potential of Mg-6%Al-5%Pb anode more negative during galvanostatic ***-6%Al-5%Pb anode with the addition of 1%(mass fraction) zinc has the best electrochemical *** activation mechanism of zinc to Mg-6%Al-5%Pb anode is as follows:The hydrolyzation of dissolved Zn2+ ions reduces the pH value of the solution near the surface of the anode and accelerates the dissolution of Mg(OH)2 film;The precipitated Zn(OH)2 with similar structure as Mg(OH)2 combines with Mg(OH)2 film easily and makes it break down.

关键词： magnesium anode alloying electrochemistry electrochemical discharge activity