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Aspects of surface and environment protection in German mining areas

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Mining Science and Technology 2009年第5期19卷 615-619页

作者： frank Otto Technische Fachhochschule Georg Agricola zu Bochum University of Applied Sciences

Hard coal mining in the German Ruhr district has a tradition of more than 200 years. Starting in the south near the river Ruhr with mining of seams near to the surface, mining wandered to the north with coal seams deeper and deeper. In the same way all environmental effects of mining wandered from south to north, as there are abandoned mining sites, contaminated areas, burning mining dumps, subsided areas and gas accesses at day ground. This all happened in a very high populated area with more than four million inhabitants. Therefore Germany has a long tradition in solving environmental problems of mining activities. The very good interaction of mine authority, mining companies and the mine workers’ union is the main reason why the problems of decreasing mining activities in Germany were solved without economic, environmental or social hazards.

关键词： abandoned mining sites contaminated areas subsidence burning mining dumps gas accesses at day ground

Membrane processes for water recovery and wastewater treatment in the food industry

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Journal of Harbin Institute of Technology(New Series) 2012年第1期19卷 75-78页

作者： frank Lipnizki Alfa Laval Copenhagen Business Centre MembranesMaskinvej 52860 SborgDenmarkfrank

Despite the efforts to reduce its water consumption,the food industry still requires large amounts of water. Membrane processes have established themselves in the food industry at the beginning of the water loop for preparation of the intake water and at the end water loop for recovery and final treatment of the water. The focus of this paper is on two application studies related to water recovery and water treatment in the food industry. The first study is on water recovery from tank washing water in customized liquid sugar production. During the washing of the tanks,sweet water with 1°- 5° Brix sugars is produced which is equivalent to a COD of 5000 - 25000 mg/L. By reverse osmosis,this sweet water can be separated into a sugar-free permeate for recycling and a concentrate with more than 20° Brix,which can be utilized as animal feed. The second study is on the effluent from production of modified potato starch,which is contaminated with spirochete bacteria resulting in problems in the wastewater treatment plant. By installing a membrane bioreactor,not only is this problem overcome but the general quality of the water at the discharge of the plant is improved. Overall,this paper demonstrates that membrane processes have a large potential in the water recovery and wastewater treatment in the food industry.

关键词： Food industry membrane bioreactor sweet water starch industry

Quantum Algorithm for Approximating Maximum Independent Sets

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Chinese Physics Letters 2021年第3期38卷 17-21页

作者： Hongye Yu frank Wilczek Biao Wu Department of Physics and Astronomy Stony Brook UniversityStony BrookNY 11794USA Center for Theoretical Physics Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA D.Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Wilczek Quantum Center School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Department of Physics Stockholm UniversityStockholm SE-10691Sweden Department of Physics and Origins Project Arizona State UniversityTempe AZ 25287USA International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

We present a quantum algorithm for approximating maximum independent sets of a graph based on quantum non-Abelian adiabatic mixing in the sub-Hilbert space of degenerate ground states,which generates quantum annealing in a secondary *** both sparse and dense random graphs G,numerical simulation suggests that our algorithm on average finds an independent set of size close to the maximum size α(G) in low polynomial *** best classical algorithms,by contrast,produce independent sets of size about half of α(G)in polynomial time.

关键词： quantum polynomial Independent

Charge carrier mobilities of organic semiconductors:ab initio simulations with mode-specific treatment of molecular vibrations

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npj Computational Materials 2022年第1期8卷 2199-2209页

作者： Sebastian Hutsch Michel Panhans frank Ortmann School of Natural Sciences Department of ChemistryTechnische Universität MünchenGarching b.MünchenGermany

The modeling of charge transport in organic semiconductors usually relies on the treatment of molecular vibrations by assuming a certain limiting case for all vibration modes,such as the dynamic limit in polaron theory or the quasi-static limit in transient localization *** opposite limits are each suitable for only a subset of ***,we present a model that combines these different *** is based on a separation of the vibrational spectrum and a quantum-mechanical treatment in which the slow modes generate a disorder landscape,while the fast modes generate polaron band *** apply the combined method to 20 organic crystals,including prototypical acenes,thiophenes,benzothiophenes,and their *** mobilities span several orders of magnitude and we find a close agreement to the experimental *** analysis reveals clear correlations to simple mobility predictors and a combination of them can be used to identify high-mobility materials.

关键词： theory semiconductors limit

A Comprehensive Review of Redirected Walking Techniques:Taxonomy,Methods,and Future Directions

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Journal of Computer Science & Technology 2022年第3期37卷 561-583页

作者： Yi-Jun Li frank Steinicke Miao Wang State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijing 100191China Department of Informatics Universität HamburgHamburg 20146Germany Peng Cheng Laboratory Shenzhen 518055China

Virtual reality(VR)allows users to explore and experience a computer-simulated virtual environment so that VR users can be immersed in a totally artificial virtual world and interact with arbitrary virtual ***,the limited physical tracking space usually restricts the exploration of large virtual spaces,and VR users have to use special locomotion techniques to move from one location to *** these techniques,redirected walking(RDW)is one of the most natural locomotion techniques to solve the problem based on near-natural walking *** core idea of the RDW technique is to imperceptibly guide users on virtual paths,which might vary from the paths they physically walk in the real *** a similar way,some RDW algorithms imperceptibly change the structure and layout of the virtual environment such that the virtual environment fits into the tracking *** this survey,we first present a taxonomy of existing RDW *** on this taxonomy,we compare and analyze both contributions and shortcomings of the existing methods in detail,and find view manipulation methods offer satisfactory visual effect but the experience can be interrupted when users reach the physical boundaries,while virtual environment manipulation methods can provide users with consistent movement but have limited application ***,we discuss possible future research directions,indicating combining artificial intelligence with this area will be effective and intriguing.

关键词： virtual reality locomotion redirected walking

Detoxification of ferrocyanide in a soil–plant system

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Journal of Environmental Sciences 2019年第3期31卷 54-64页

作者： Tsvetelina Dimitrova frank Repmann Dirk Freese Brandenburg University of Technology Cottbus-Senftenberg

The detoxification of iron cyanide in a soil–plant system was investigated to assess the total cyanide extracted from contaminated soil and allocated in the leaf tissue of willow trees(Salix caprea). They were grown in soil containing up to 1000 mg/kg dry weight(dw) of cyanide(CN),added as ^(15)N-labeled potassium ferrocyanide and prepared with a new method for synthesis of labeled iron cyanides. CN content and ^(15)N enrichment were monitored weekly over the exposure in leaf tissue of different age. The ^(15)N enrichment in the young and old leaf tissue reached up to 15.197‰ and 9063‰, respectively; it increased significantly over the exposure and with increasing exposure concentrations(p < 0.05). Although the CN accumulation in the old leaf tissue was higher, compared to the young leaf tissue(p < 0.05), the ^(15)N enrichment in the two tissue types did not differ statistically. This indicates a non-uniform CN accumulation but a uniform ^(15)N allocation throughout the leaf mass. Significant differences were detected between the measured CN content and the C^(15)N content, calculated from the ^(15)N enrichment(p < 0.05), revealing a significant CN fraction within the leaf tissue, which could not be detected as ionic CN. The application of labeled iron CN clearly shows that CN is detoxified during uptake by the willows. However, these results do not exclude other detoxification pathways, not related to the trees. Still, they are strongly indicative of the central role the trees played in CN removal and detoxification under the experimental conditions.

关键词： Iron cyanide Detoxification Exposure Phytoremediation

Role of dietary phospholipids and phytosterols in protection against peptic ulceration as shown by experiments on rats

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World Journal of Gastroenterology 2015年第5期21卷 1377-1384页

作者： frank I Tovey Division of Surgery and Interventional Science University College LondonLondon W1W 7EJUnited Kingdom

Geographically the prevalence of duodenal ulceration is related to the staple foods in the diet in regions of developing countries where the diet is *** is higher in regions where the diet is based on milled rice,refined wheat or maize,yams,cassava,sweet potato,or green bananas,and is lower in regions where the staple diet is based on unrefined wheat or maize,soya,certain millets or certain *** on rat gastric and duodenal ulcer models showed that it was the lipid fraction in staple foods from low prevalence areas that was protective against bothgastric and duodenal ulceration,including ulceration due to non-steroidal anti-inflammatory drugs(NSAIDs).It also promoted ulcer *** lipid from the pulse,Dolichos biflorus,horse gram which was highly protective was used to identify the fractions with protective activity in the *** protective activity lay in the phospholipid,sterol and sterol ester *** the phospholipid fraction phosphatidyl choline(lethicin) and phosphatidyl ethanolamine(cephalin) were *** the sterol fraction the sub-fractions showing protective activity contained β-sitosterol,stigmasterol,and an unidentified isomer of β-*** evidence from animal models shows that certain dietary phospholipids and phytosterols have a protective action against gastroduodenal ulceration,both singly and in *** supports the protective role of staple diets in areas of low duodenal ulcer prevalence and may prove to be of importance in the prevention and treatment of duodenal ulceration and management of recurrent ulcers.A combination of phospholipids and phytosterols could also play an important role in protection against ulceration due to NSAIDs.

关键词： Peptic ulceration Mucosal protection Nonsteroidal

Euler-Lagrange/DEM simulation of wood gasification in a bubbling fluidized bed reactor

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Particuology 2009年第4期7卷 307-316页

作者： Michael Oevermann Stephan Gerber frank Behrendt Berlin Institute of Technology School of Process Sciences and EngineeringDepartment of Energy Engineering Fasanenstr.8910623 BerlinGermany

We present an Euler-Lagrange method for the simulation of wood gasification in a bubbling fluidized bed. The gas phase is modeled as a continuum using the 2D Navier-Stokes equations and the solid phase is modeled by a Discrete Element Method （DEM） using a soft-sphere approach for the particle collision dynamic. Turbulence is included via a Large-Eddy approach using the Smagorinsky sub-grid model. The model takes into account detailed gas phase chemistry, zero-dimensional modeling of the pyrolysis and gasification of each individual particle, particle shrinkage, and heat and mass transfer between the gas phase and the particulate phase. We investigate the influence of wood feeding rate and compare exhaust gas compositions and temperature results obtained with the model against experimental data of a laboratory scale bubbling fiuidized bed reactor.

关键词： Euler-Lagrange simulation Discrete element method (DEM) Dense fluidized bed Biomass gasification

Resonant Quantum Search with Monitor Qubits

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Chinese Physics Letters 2020年第5期37卷 15-19页

作者： frank Wilczek Hong-Ye Hu Biao Wu Center for Theoretical Physics MITCambridgeMA 02139USA D.Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Wilczek Quantum Center School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Department of Physics Stockholm UniversityStockholmSE-10691Sweden Department of Physics Arizona State UniversityTempeAZ 25287USA Department of Physics University of CalifornianSan DiegoCA 92093USA International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

We present an algorithm for the generalized search problem(searching k marked items among N items)based on a continuous Hamiltonian and exploiting *** resonant algorithm has the same time complexity O(√N/k)as the Grover algorithm.A natural extension of the algorithm,incorporating auxiliary"monitor"qubits,can determine k precisely,if it is *** time complexity of our counting algorithm is O(√N),similar to the best quantum approximate counting algorithm,or better,given appropriate physical resources.

关键词： resonant Hamiltonian auxiliary