检索结果-南通市图书馆

Influence of the Nature of the Incoming Sludge on the Performance of a Vertical Flow Reed Beds in Dakar-Senegal

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2024年第6期16卷 429-449页

作者： elhadji mamadou Sonko Dioma.e dieng maïmouna Lo Cheikh Diop Laboratoire detude environnemental des Milieux Urbains (LeeMUR) Institut des Sciences de lEnvironnement (ISE) Facult des Sciences et Technique (FST) Universit Cheikh Anta Diop de Dakar (UCAD) Dakar-Fann Sngal

This work investigates the influence of the type sludge on drainage, plant development, purification performances and biosolids quality. Drainage properties were measured through the frequency of clogging, the percentage of leachate recovered and the dryness of accumulated sludge. Plant development was measured through the density, the height and the stem diameter. Purification performance was evaluated from the reduction rate. Biosolids quality was measured after 3 months of maturation. The results show that the clogging frequencies were 9.5%;0% and 3.7%;the volume of leachate recovered was 42.2%;20.4% and 24.7% and, the dryness was 33.4%;61.1% and 52.4% for FS-ST, FS-STT and SS respectively. Plants densities were about, with densities 197.1, 171.3 and 178.3 plants/m2 in beds fed respectively with FS-ST, FS-STT and SS. Despite the high removal rates, the concentrations of pollutants in the leachates are above the Senegalese standard NS 05-061 for discharge into the environment. The biosolids are all mature with C/N and NH4+/NO3?ratios lower than 12 and 1 respectively. The biosolids are also rich in organic and mineral elements. The concentrations of Ascaris eggs are higher than the WHO recommendations. These biosolids should be stored for additional time or composted.

关键词： Biosolid Quality Dewatering Performance Planted Drying Beds Purification Performance Sludge Type

Surgical Treatment of Upper Urinary Tract Lithiasis in Conakry

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Urology 2024年第9期14卷 487-498页

作者： Barry mamadou madiou Diallo thierno Oumar Sow thierno Amadou Oury Diallo thierno mamadou Oury Bah Ibrahima Bah mamadou Diao Cissé Demba Bah Oumar Raphiou Service dUrologie Hpital National Ignace Deen Universit Gamal Abdel Nasser de Conakry Conakry Guinea

Introduction: The management of urinary lithiasis in our settings has long been conventional surgery. The recent introduction of endoscopy of the upper urinary tract represents a major advance in our department. The aim was to contribute to the study of the treatment of lithiasis of the upper urinary tract in Conakry and to report on our initial experience of ureteroscopy in Conakry. Methodology: This is a prospective descriptive study lasting one year, from January 1 to December 31, 2022, carried out at the Urology Department of the Ignace Deen National Hospital and at the PeRCHIN Urological Clinic. The study included all patients treated surgically for lithiasis of the upper urinary tract who met the selection criteria. Results: The study included 57 patients. The mean age was 30 years, with extremes of 20 and 73 years;the most represented age group was 31 to 40 years, followed by 20 to 30 years with 29.9% and 26.3% respectively. ma.es predominated in 36 cases (63.15%), with a M/F sex ratio of 1.71. Left-sided renal colic was the most common, at 75.43% (n=43), and right-sided renal colic at 40.35%, associated with digestive signs at 43.85%. 77.19% had normal creatinine levels before surgery, versus 22.81% with elevated creatinine levels, i.e. 15.78% improvement in renal function after surgery. Urinary tract infection was found in 47.36%, and escherichia coli in 31.57%, followed by staphylococcus aureus in 8.77%. Overall, 82.45% of patients had organic dama.e to the kidneys or ureters. Right ureterohydronephrosis was noted in 56.14%, followed by left hydronephrosis in 26.32%. Open surgery was predominant in 52.63% of cases, with endoscopic surgery (URS) accounting for a significant 47.36% during the study period. The endoscopic treatment used was laser ureteroscopy. In our study, 73.68% underwent drainage of the upper excretory tract, including 64.91% with a JJ catheter. The average length of stay was 07 days, with extremes of 02 and 28 days, and 81.4% of patients

关键词： Urinary Lithiasis Surgical Treatment Ureteroscopy Upper Urinary Tract Conakry

elasticity meets topology

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 84-85页

作者： Guancong ma Department of Physics Hong Kong Baptist University

We are surrounded by environments and items that are ma.e from solid ma.erials in our daily life. Any physical contact with any items is a mechanical disturbance that produces mechanical *** underlines the crucial role that such vibrations play in our daily interactions,highlighting the need for a deeper understanding and improved manipulation of these fundamental phenomena.

关键词：

Uniform decomposition of velocity gradient tensor

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第1期36卷 24-34页

作者： Chenxi ma Chaoqun Liu Department of mathematics University of Texas at ArlingtonArlingtonTXUSA

In this paper,the principal decomposition of the velocity gradient tensor[∇v]is discussed in 3 cases based on the discriminant∆:∆0 with 3 distinct real eigen values,and∆=0 with 1 or 2 distinct real eigen *** velocity ... 详细信息

In this paper,the principal decomposition of the velocity gradient tensor[∇v]is discussed in 3 cases based on the discriminant∆:∆eal eigen value and a pair of conjugate complex eigen values,∆>0 with 3 distinct real eigen values,and∆=0 with 1 or 2 distinct real eigen *** velocity gradient tensor can also be classified as rotation point,which can be decomposed into three parts,i.e.,rotation[R],shear[S]and stretching/compression[SC],and non-rotation point,we defined a new resistance term[L],and the tensor can be decomposed into three parts,i.e.,resistance[L],shear[S]and stretching/compression[SC].example matric are also displayed to demonstrate the new *** of principal decomposition between 3 different cases,and between Resistance and Liutex will also be discussed.

关键词： Velocity gradient Liutex resistance fluid kinematics

VOC emitted by biopharma.eutical industries:Source profiles,health risks,and secondary pollution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of environmental Sciences 2024年第1期135卷 570-584页

作者： Jiawei ma Lin Li State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China National engineering Laboratory for VOCs Pollution Control ma.erial&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharma.eutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental *** study conducted an on-site investigation of the process-based emission of VOCs from three biopharma.eutical *** the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing *** were the main components of waste gases,accounting for 44.13%-77.85%of the overall ***-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC *** heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGMe),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation *** level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km ***,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGMe should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of *** results provide a basis for understanding the characteristics of VOC emission by biopharma.eutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharma.eutical Volatile organic compound Priority pollutant exposure risk Secondary pollution

维普期刊数据库

Deterministic and Robust Volt-var Control Methods of Power System Based on Convex Deep Learning

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean energy 2024年第3期12卷 719-729页

作者： Qing ma Changhong Deng the School of electrical engineering and Automation Wuhan UniversityWuhanChina

Volt-var control(VVC)is essentially a non-convex optimization problem due to the non-convexity of power flow(PF)constraints,resulting in the difficulty in obtaining the optimum without convexity *** existing second-order cone method for the convexity conversion often leads to a sharp increase in PF constraints and optimization variables,which in turn increases the optimization difficulty or even leads to optimization *** paper first proposes a deterministic VVC method based on convex deep learning power flow(DLPF).This method uses the input convex neural network(ICNN)to establish a single convex mapping between state parameters and node voltage to complete the convexity conversion while the optimization variables only correspond to reactive power equipment,which can ensure the global optimum with extremely fast computation *** cope with the impact brought by the uncertainty of distributed energy and omit the additional worst scenario search of traditional robust VVC,this paper proposes robust VVC method based on convex deep learning interval power flow(DLIPF),which continues to adopt ICNN to establish another convex mapping between state parameters and node voltage *** DLIPF with DLPF,this method decreases the modeling and optimization difficulty of robust VVC *** results on 30-bus,118-bus,and 200-bus systems prove the correctness and rapidity of the proposed methods.

关键词： Volt-var control convexity conversion convex deep learning power flow

维普期刊数据库

Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical engineering 2024年第1期65卷 43-53页

作者： Dong ma Qinhui Wang State Key Laboratory of Clean energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by ***,the PG decomposition temperature remains high and the product yield remains *** adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be ***,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic ***,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same *** effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting ***,the reaction mechanism is *** is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition *** example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) *** process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed.

关键词： Phosphogypsum Sulfur dioxide Copper slag Fluidized-bed Reduction Waste treatment

维普期刊数据库

A review of recent advances in the effects of surface and interface properties on marine propellers

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第2期12卷 185-214页

作者： manfu ZHU Liran ma State Key Laboratory of Tribology in Advanced equipment Tsinghua UniversityBeijing 100084China

marine propellers are important propulsion devices for both surface ships and underwater *** severe environmental problems have required further performance enhancement for ***,traditional methods to improve propeller performances through geometrical and structural optimizations have been extensively investigated,while the underlying mechanisms of the effects of surface and interface properties on marine propellers are still far from being fully *** paper presented a comprehensive review of recent advances in the effects of surface and interface properties,such as surface roughness and surface wettability,on marine propellers with an emphasis on the significant improvements in both hydrodynamic and cavitation performances,hoping to arouse more in-depth investigations in the field of surface/interface science and technologies on marine propellers,and also promote the state-of-the-art technologies,such as superlubricity technology,into practical applications.

关键词： marine propellers hydrodynamics cavitation surface roughness surface wettability

On the Security of Homomorphic encryption Schemes with Restricted Decryption Oracles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第5期37卷 2240-2261页

作者： ma Guangsheng LI Hongbo School of mathematics and Physics North China Electric Power University Academy of mathematics and Systems Science Chinese Academy of Sciences University of Chinese Academy of Sciences

Fully homomorphic encryption（FHe） can be used for privacy-preserving aggregation of medical data. In this typical application, the security against passive attacks has been well studied by Li and Micciancio（2021）. In this paper, the authors further consider a “nearly passive” kind of attack, where the attacker may behave like a passive attacker in the view of the third-party *** capture the security against this hard-to-detect attack, the authors propose a new notion of IND-CPArDsecurity. The authors show that the standard LWe encryption and its related FHe schemes can not defend against IND-CPArDattack, even under a stricter rule limiting the content and number of queries ma.e by the attacker. To ma.e the application of FHe schemes more secure, the authors discuss some possible modifications that may serve as countermeasures to IND-CPArDattack.

关键词： Homomorphic encryption privacy secure cloud computing security