nils-herrmann/clean_scirepeval huggingface dataset:
Conceptual design of clean separation of ternary mixture of acetone-tetrahydrofuran-water

Based on the thermodynamics analysis of the mixture of acetone, tetrahydrofuran (THF) and water, the conceptual design of a clean separation process for this mixture was developed. Extractive distillation was used to separate water from the other two components. Different extractive solvents were compared through simulation with Aspen plus and it was found that triethylene glycol (TEG) was a highly selective and energy saving solvent.The extracted water could be separated from extractive solvent by ordinary distillation.The simulation results from Aspen plus showed that the separation of THF and acetone could be achieved by azeotropic distillation using cyclohexane or carbon bisulfide (CS_2) as azeotropic solvent according to different end requirements. When CS_2 was used as azeotropic solvent, high purity THF could be obtained while accompanied by with high energy cost due to low CS_2 content in the binary azeotropic mixture of CS_2 and acetone.If cyclohexane was used as azeotropic solvent, a great deal of energy could be saved at the sacrifice of reduced purity THF.The separation of an azeotropic solvent and acetone could be realized through a liquid-liquid extraction process using water as extractive solvent. No waste water and other waste liquid were produced during the whole separation process thanks to the recycling of extractive solvent and azeotropic solvent.Therefore the separation process developed here could be considered as a clean separation process.

Field of study: Chemistry, Environmental science
Absolute sphericity measurement.

Several conventional methods for absolute sphericity testing of optical surfaces are known. One method has been used previously for real time interferometry, but a detailed investigation has not been carried out so far. In this work the known conventional methods are reviewed and assessed for suitability in real time interferometry. One method has been applied to phase stepping interferometry and examined. Adjustment peculiarities, experimental results of deviation measurements on normal surfaces, and application of normals are reported. Measuring errors, especially coherent noise, are analyzed and a special subsequent digital spatial filtering technique for diminution of noise is described.

Field of study: Physics
CONTINUOUS AMMONIA EMISSION MEASUREMENTS FROM A COMMERCIAL BEEF FEEDYARD IN TEXAS

Ammonia emissions from cattle feedlots pose the potential to react with other compounds such as oxides of nitrogen and sulfur, which lead to detrimental environmental effects. Ambient ammonia (NH3) concentrations were measured continuously at a beef cattle feedyard for 12 months beginning in March 2007. Concentrations were measured every 5 min, 24 hours per day, at a sample intake height of 3.3 m using a chemiluminescence analyzer. On-site weather data were collected concurrently. Modeled emissions of NH3 were compared with the mass balance of N for the feedyard. Mean annual NH3 concentrations were 0.57 ppm, with a monthly average low of 0.37 ppm in December 2007 and a monthly average high of 0.77 ppm in August 2007. Flux densities were calculated using a backward Lagrangian stochastic model (WindTrax 2.0.7.8). Mean annual flux density was 70.7 µg m-2 s-1 (2.2 kg m-2 year-1). Mean monthly flux density ranged from 42.7 to 123.1 µg m-2 s-1 (0.11 to 0.32 kg m-2 month-1) in November and April 2007, respectively. Both concentration and flux density had a diel distribution with minima during the nighttime hours and maxima during the early afternoon. On an annual basis, 48.8% of fed N was volatilized as NH3. The inverse modeled daily ammonia production per head was 85.3 g NH3-N (head fed)-1 d-1.

Field of study: Agricultural and Food sciences
Search for New Heavy Higgs Boson in B-L model at the LHC using Monte Carlo Simulation

The aim of this work is to search for a new heavy Higgs boson in the B-L extension of the Standard Model at LHC using the data produced from simulated collisions between two protons at different center of mass energies by Monte Carlo event generator programs to find new Higgs boson signatures at the LHC. Also we study the production and decay channels for Higgs boson in this model and its interactions with the other new particles of this model namely the new neutral gauge massive boson and the new fermionic right-handed heavy neutrinos .

Field of study: Physics
Biphasic changes in the levels of N-methyl-D-aspartate receptor-2 subunits correlate with the induction and persistence of long-term potentiation.

N-Methyl-D-aspartate glutamate receptors (NMDAR) form ion channels made up of polypeptides from two classes of subunits; NR1 is obligatory for function whereas members of the NR2 class regulate the properties of the channel. Long-term potentiation (LTP) of synaptic transmission is an event largely dependent on NMDAR activation, and is studied as the primary cellular model of memory in the mammalian brain. While there has been a focus on non-NMDARs in mediating the expression of LTP, we report here biochemical evidence for plasticity of the NMDAR that is associated with LTP persistence in awake animals. Following the establishment of LTP in perforant path synapses of the dentate gyrus, we observed a rise in NR2B protein levels 48 h post-tetanus which was dependent upon activation of NMDARs during the tetanization, and which strongly correlated with the degree of LTP measured at this time-point. We also observed a transient increase in both NR2B and NR2A protein levels 20 min post-tetanus that returned to control levels by 4 h. These early increases were not observed in anaesthetized animals which do not sustain persistent LTP. Our data demonstrate a marked plasticity of NMDAR subunit expression, which may affect LTP persistence, as well as the subsequent ability to induce LTP at previously activated synapses.

Field of study: Biology
Über den 2.4-Dichlor-thiophen-aldehyd-(5)

Aus 2.3.4.5-Tetrachlor-tetrahydrothiophen durch Dehydrohalogenierung erhaltenes 2.4-Dichlor-thiophen wird chlormethyliert und die Chlormethylverbindung mit Blei(II)-nitrat zum 2.4-Dichlor-thiophen-aldehyd-(5) (I) oxydiert (Ausbeute 38% d. Th.). Der durch einige Derivate charakterisierte Aldehyd reagiert in der Cannizzaro-Reaktion normal und gibt mit Nitromethan 5-[2-Nitro-athen-(1)-yl-(1)]-2.4-dichlor-thiophen (II).

Field of study: Chemistry
[Clinical-neuropsychological aspects of the adaptation of patients after the excision of craniopharyngioma in childhood].

: 40 patients aged 9-36 years were followed-up for at least 10 years after craniopharyngiomectomy. A combined neuropsychologic study according to A.R. Luria was carried out both for determination of the degree of psychic defects and for comparison with possibilities of adaptation. Symptoms of a damage of medio-basal regions of the frontal lobes and dyencephalic region were observed in all the patients. The frontal symptoms were decisive for social adaptation after the operation. The adaptation was worse in patients with more pronounced manifestations of frontal symptoms in involvement of medio-basal regions of the left frontal lobe accompanied by poor motivation and inertness. Patients with infact motivation and activity in the presence of dominant dysfunction of the medio-basal regions of the right frontal lobe appeared to be more adapted, even when there were pronounced disorders of vision and memory. The defects were compensated worse in patients operated early in childhood, with features of side cerebral dysfunction and in left-handers.

Field of study: Medicine, Psychology
Phenomenological model of a solid electrolyte NOx and O2 sensor using temperature perturbation for on-board diagnostics

Amperometric NOx sensors are increasingly used in automotive industry to meet the stringent emission measurement regulations. These sensors measure O2 and NOx concentration using two different sensing cells. In this work, a physics-based model was developed and then employed to predict the sensor output for oxygen as a function of sensor temperature and oxygen concentration. A temperature perturbation method was also developed based on the model to calibrate the sensor output with respect to oxygen concentration. The model accurately matched the experimental results for steady state and transient conditions. A two step sensor diagnostics procedure based on the sensor temperature perturbation method was then proposed. The first diagnostics step evaluates the sensor output to check if it is within the acceptable range. The second diagnosis step checks the plausibility of the sensor output based on the physics based model and temperature perturbation. A self-calibration procedure was also implemented inside the diagnostics procedure using temperature perturbation at engine-off. This self-recalibration only requires an external relative humidity measurement.

Field of study: Materials science
How Entrepreneurial Firms Prosper while Larger Firms Crumble

Many firms are facing great difficulty surviving the declining financial markets in Fall 2008. As larger firms take drastic measures to control and cut costs while forecasting declining revenue, entrepreneurial firms view the same marketplace in a more positive light. What separate these two types of firms is their differing levels of entrepreneurial intensity. An entrepreneurial grid positions firms upon two dimensions: Frequency of Entrepreneurship and Degree of Entrepreneurship (innovativeness, risk taking, and proactiveness). Just as managers select the placement of their firm on market dimensions such as quality and price, firms need to make a strategic position choice on where they wish their firm to be placed as related to entrepreneurial intensity. The firms listed in a recent article from BusinessWeek magazine titled “The World’s Most Innovative Companies” portrays a higher level of entrepreneurial efforts on both dimensions; firms that would be labeled as revolutionary on the entrepreneurial grid. It would be expected that as consumers expect new and improved products and services to emerge from innovative markets, firms labeled as periodic/incremental would have difficulties in sustaining continual growth. Additionally, firms labeled as continuous or incremental, dynamic, and periodic or discontinuous on the grid would be expected to have moderate success.

Field of study: Business
Application of spectral coherence analysis to describe the relationships between ambient ozone exposure and crop growth.

Growth season-based time series spectral coherence analysis was performed between weekly changes in hourly ambient O(3) concentrations and weekly changes in alfalfa height growth. Weekly median hourly O(3) concentration and the corresponding weekly cumulative integral (sum of all hourly concentrations within the week) were used as indicators of weekly O(3) spectral density and coherence with the change in weekly alfalfa height growth. In general, the weekly cumulative integral performed much better than the weekly median O(3) concentration. A conceptual analysis of the results is presented, along with a recommendation that crop growth stage-based cumulative integrals merit further evaluation towards a better understanding of cause-effect relationships.

Field of study: Environmental science
Research of Content Delivery Networks Primary Technologies

Content Delivery Networks(CDN)is a creative application of Internet.With the help of the new layer added to the original internet architecture,CDN can send the website content to the″edge″of its nearest users and deliver the data of streaming media effectively in the internet.Therefore the load of server and the crowding of internet can be relieved greatly,the reply speed also can be quickened,and the quality of service(QoS)can be improved to a great extent,too.This paper mainly introduced the architecture and workflow of CDN and its primary tech-nologies in detail.With the development of the Wide Brand,the application of CDN is certain to be the main trend in future high speed networks.

Field of study: Computer science
An elementary introduction to entropy via irreversibility

An outline is given of an approach to thermodynamics in which entropy is derived directly, from a simple postulate of direct experimental significance, without reference to temperature or thermal equilibrium The author first shows how the irreversibility of a natural process may be quantitatively measured; entropy is then defined so that its increase in any process equals the irreversibility. Lastly equilibrium states are defined and absolute temperature is derived from entropy by differentiation.

Field of study: Chemistry
Betaglycan (TGFBR3) up-regulation correlates with increased TGF-β signaling in Marfan patient fibroblasts in vitro.

Marfan syndrome (MFS), a congenital connective tissue disorder leading to aortic aneurysm development, is caused by fibrillin-1 (FBN1) gene mutations. Transforming growth factor beta (TGF-β) might play a role in the pathogenesis. It is still a matter of discussion if and how TGF-β up-regulates the intracellular downstream pathway, although TGF-β receptor 3 (TGFBR3 or Betaglycan) is thought to be involved. We aimed to elucidate the role of TGFBR3 protein in TGF-β signaling in Marfan patients.



Dermal fibroblasts of MFS patients with haploinsufficient (HI; n=9) or dominant negative (DN; n=4) FBN1 gene mutations, leading to insufficient or malfunctioning fibrillin-1, respectively, were used. Control cells (n=10) were from healthy volunteers. We quantified TGFBR3 protein expression by immunofluorescence microscopy and gene expression of FBN1, TGFB1, its receptors, and downstream transcriptional target genes by quantitative polymerase chain reaction.



Betaglycan protein expression in FBN1 mutants pooled was higher than in controls (P=.004) and in DN higher than in HI (P=.015). In DN, significantly higher mRNA expression of FBN1 (P=.014), SMAD7 (P=.019), HSP47 (P=.023), and SERPINE1 (P=.008), but a lower HSPA5 expression (P=.029), was observed than in HI. A pattern of higher expression was noted for TGFB1 (P=.059), FN1 (P=.089), and COL1A1 (P=.089) in DN as compared to HI. TGFBR3 protein expression in cells, both presence in the endoplasmic reticulum and amount of vesicles per cell, correlated positively with TGFB1 mRNA expression (Rs=0.60, P=.017; Rs=0.55, P=.029; respectively). TGFBR3 gene expression did not differ between groups.



We demonstrated that activation of TGF-β signaling is higher in patients with a DN than an HI FBN1 gene mutation. Also, TGFBR3 protein expression is increased in the DN group and correlates positively with TGFB1 expression in groups pooled. We suggest that TGFBR3 protein expression is involved in up-regulated TGF-β signaling in MFS patients with a DN FBN1 gene mutation.

Field of study: Biology, Medicine
Organizational structures used in software development by the U.S. aerospace industry

The U.S. aerospace industry is generally credited with developing the engineering project to the degree to which it is used today. In the 1950s, the development of large systems was accomplished primarily by project organization. Later in the 1960s and 1970s, matrix organization began to replace project organization as a means of obtaining maximum use of scarce personnel resources. In an attempt to find out more about the organizational structures used in the U.S. aerospace industry, a survey was conducted of a selected sample of the industry. This article, reporting on the results of that survey, shows that 38% of software developments are accomplished by project organization, 58% by matrix organization, and 4% by functional organization. Other organizational structures are identified and reported. A comparison is made between selected variables denoting project information and organizational type.

Field of study: Computer science, Engineering
Innovative use of sweet sorghum juice in the beverage industry.

Sweet sorghum juice, obtained from low water consuming, drought resistant, short duration and seed-propagated sweet sorghum crop, was explored as a source to obtain syrup which can be used as sugar alternative for meeting certain requirements of the beverage industry. Value addition, through conversion of the juice to syrup and beverages, offers farmers an excellent opportunity to improve farm income and productivity in semi arid regions. In this study a new method to produce clarified sweet sorghum juice is demonstrated. The sweet sorghum juice was clarified using pre heating followed by vacuum filtration using a filter aid. The clarified juice was concentrated to syrup with acceptable sensory qualities. Flavoured beverage formulations were optimised using the clarified juice and syrup. Nutritional and sensory properties of the developed beverages showed that the samples were acceptable to the consumers and rated at par with a commercially available beverage. This work has immense industrial and social significance.

Field of study: Agricultural and Food sciences
ELASTIC-PLASTIC ANALYSIS OF A LONG-SPAN CONCRETE FILLED STEEL-TUBE TRANSMISSION TOWER UNDER EARTHQUAKE ACTION

The elastic-plastic analysis of a long-span Concrete Filled Steel-Tube(CFST) transmission tower under earthquake actions is studied by the static method and the dynamic method,including: 1) fine FEM models of a CFST tower and a tower-line system are built and the nonlinear material models including steel-tube and CFST are also modeled.2) shear forces on supports obtained by a mode-decomposition response spectrum method are distributed at all nodes based on the structural first-order mode value and then the nodal loads increase step by step in order to impel materials into plastic status until calculation cannot converge.Static analysis shows there are some steel-tube elements failed but no any CFST element failed and the limit load is decided by the steel-tube elements.3) a seismic record is selected to analyze the seismic elastic-plastic behaviors of the tower by a time-history analysis method.The dynamic analysis shows a lot of elements enter the plastic status soon after earthquake action and there are some steel-tube elements failed but no any CFST element failed at last time,so the tower can achieve the goal: no collapse in the big earthquake.The two methods both show the weakest part is in the middle of the tower.

Field of study: Engineering
Spatial transformation of the discrete sound field from a propeller

A technique for the spatial transformation of the discrete sound field from a propeller is proposed that is based on solving the Ffowcs Williams and Hawkings equation with quadrupole source term neglected. Since the blade surface velocity is fully specified, numerical inversion of Farassat's integral is used to relate the blade surface pressures to the finite number of measurements in the acoustic field. With the reconstructed aerodynamic loading, the whole sound field is naturally predicted using Farassat's integral. Since the inverse problem is ill posed, the Tikhonov regularization method is used to stabilize the solution. The optimal regularization parameter is chosen by generalized cross-validation criterion. Numerical results show that the reconstruction is inaccurate in the presence of measurement noise (error) but the spatial transformation of discrete sound filed remains satisfactory.

Field of study: Physics
The Research of Copper Ion Doped Lanthanum Silicate Electrolyte

La9.33Si6-xCuxO26-x powders with high purity were prepared. Using XRD, IR, SEM and ac impedance spectrum, crystal structure, surface microstructure and conductivity properties were respectively characterized. The results showed that the La9.33Si6-xCuxO26-x grains embrace the crystal structure of p63/m apatite and the optimum sintering temperature of La9.33Si6-xCuxO26-x electrolyte was 1500 ℃. The ac impedance spectrum test for the La9.33 Si6 xCuxO26 - x (x = 0.1, 0.2, 0.1, 0.2, 0.5) in different temperature conductivity showed that La9.33Si6-xCuxO26-x had the highest ionic conductivity which value was up to 0.0735 S·cm-1 when the doping content was 0.3.

Field of study: Engineering
Zinc Isotope Variability in Three Coal-Fired Power Plants: A Predictive Model for Determining Isotopic Fractionation during Combustion.

The zinc (Zn) isotope compositions of feed materials and combustion byproducts were investigated in three different coal-fired power plants, and the results were used to develop a generalized model that can account for Zn isotopic fractionation during coal combustion. The isotope signatures in the coal (δ(66)ZnIRMM) ranged between +0.73 and +1.18‰, values that fall well within those previously determined for peat (+0.6 ±2.0‰). We therefore propose that the speciation of Zn in peat determines the isotope fingerprint in coal. All of the bottom ashes collected in these power plants were isotopically depleted in the heavy isotopes relative to the coals, with δ(66)ZnIRMM values ranging between +0.26‰ and +0.64‰. This suggests that the heavy isotopes, possibly associated with the organic matter of the coal, may be preferentially released into the vapor phase. The fly ash in all of these power plants was, in contrast, enriched in the heavy isotopes relative to coal. The signatures in the fly ash can be accounted for using a simple unidirectional fractionation model with isotope fractionation factors (αsolid-vapor) ranging between 1.0003 and 1.0007, and we suggest that condensation is the controlling process. The model proposed allows, once the isotope composition of the feed coal is known, the constraining of the Zn signatures in the byproducts. This will now enable the integration of Zn isotopes as a quantitative tool for the source apportionment of this metal from coal combustion in the atmosphere.

Field of study: Environmental science
Use of an osteoconductive agent (Norian) in anterior surgical management of odontoid fractures. Technical note.

Odontoid fractures can be successfully treated with anterior screw fixation. Odontoid fractures commonly occur in older patients who may have significant osteopenia. The authors examined the use of a bone substitute to overcome limitations encountered during a procedure in which anterior odontoid screw fixation is performed. Two elderly patients with displaced, reducible acute odontoid fractures underwent anterior odontoid screw fixation. The intraoperative failure of the anterior vertebral cortex from osteopenic bone and failure to achieve complete contact between the dens and axis were encountered. The defects were supplemented by using the osteoconductive agent Norian. Outcome was evaluated to determine the utility of this method. Occasional intraoperative failure of anterior odontoid screw fixation may be encountered. Supplementation of bone defects with this osteoconductive agent may facilitate successful bone union in selected patients.

Field of study: Medicine
Influence of chaos on the fusion enhancement by electron screening

We study the effect of screening by bound electrons in low energy nuclear reactions. We use molecular dynamics to simulate the reactions involving many electrons: D+d, D+D, 3He+d, 3He+D, 6Li+d, 6Li+D, 7Li+p, 7Li+ H. Quantum effects corresponding to the Pauli and Heisenberg principles are enforced by constraints in terms of the phase space occupancy. In addition to the well-known adiabatic and sudden limits, we propose a new “dissipative limit” which is expected to be important not only at high energies but in the extremely low energy region. The dissipative limit is associated with the chaotic behavior of the electronic motion. It affects also the magnitude of the enhancement factor. We discuss also numerical experiments using polarized targets. The derived enhancement factors in our simulation are in agreement with those extracted within the R-matrix approach.

Field of study: Physics