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The high capacity of SnO2 (tin oxide) and high rate capability of Li4Ti5O12 (lithium titanate, LTO) were pooled together for engineering a composite Li ion anode material in hollow fiber edifice by sol-gel/electrospinning. The electrospun porous precursor composite hollow fibers (CHFs) were heat treated either in air (SnO2/LTOA) or argon (SnO2/LTOAr) atmosphere to control grain size, porosity and presence of Ti3+ content. The morphological study performed using Field Emission Scanning Electron Microscopy and Transmission Electron Microscopy revealed smaller grain size (5–10 nm) for SnO2/LTOAr CHFs. Further, X-Ray Diffraction and X- Ray Photoelectron Spectroscopy studies illustrated a significant variation in the crystallinity and the elemental oxidation states in these CHFs respectively. Brunauer-Emmett-Teller measurements exposed the presence of high surface area and pore volume in SnO2/LTOAr CHFs. Further, the half-cell galvanostatic charge-discharge performances of SnO2/LTOAr CHFs at 1 C rate revealed a stable specific capacity of 300 mA h/g for 110 cycles with 90% capacity retention. The stable and high capacity of SnO2/LTOAr CHFs were corroborated to the presence of smaller grain size, high porosity and conductive Ti3+ providing faster lithium ion diffusion when compared to SnO2/LTOA CHFs. Electrochemical Impedance Spectroscopy study confirmed low impedances in SnO2/LTOAr CHFs due to low charge transfer and electrolyte resistances. Moreover, Li ion full-cell study performed using LiFePO4 (LFP) cathode (3 V), delivered a specific capacity of 230 mAh/g at 0.1 C rates. The excellent electrochemical performance of SnO2/LTOAr CHFs in both half-cell and full-cell modes illustrated the significance of sol-gel/electrospinning in synthesizing high performance Lithium ion batteries in a cost effective and scalable way.

Critical heat fluxes (CHFs) for subcooled flow boiling of water in a vertical tube due to steady and exponentially heat inputs were measured. The platinum tube with an inner diameter of 2.0 mm and a length of 94.8 mm was placed vertically in the experimental water loop. The upward flow velocity was approximately 2.5 m/s and the outlet subcooling ranged from 18 to 48 K. The heat generation rate was varied exponentially to investigate the effect of e-folding time on the CHFs. As an experimental result, the CHFs increased with a decrease in the e-folding time. When the e-folding times were longer, the CHFs were almost constant, whereas the CHFs increased for shorter e-folding times. The CHFs were independent on outlet subcoolings at low flow conditions. Moreover, it was considered that the explosive-like CHF occurred when the inner surface temperature of the tube exceeded the lower limit of heterogeneous spontaneous nucleation (HSN) temperature.

High critical heat fluxes (CHFs) for subcooled boiling of water in a small tube were investigated experimentally. A platinum tube with an inner diameter of 1.0 mm and a length of 40.9 mm was used in the experiment. The upward flow velocity, the subcooling of water, and the outlet pressure of the experimental tube were varied to enable a parametric study of the CHFs. The flow velocity ranged from 9 to 13 m/s and the inlet subcooling ranged from 69 to 148 K. The boiling number decreased with increasing Weber number. The boiling number is also dependent on a non-dimensional parameter and the density ratio of liquid to vapor. A correlation for the high CHF of the small tube was obtained based on the experimental data. Finally, the high CHF correlation was evaluated using the CHF data obtained by other researchers.

A rapid, continuous, environmentally benign and innovative approach is employed for the synthesis of green fluorescent graphene quantum dots (GQD) with low cytotoxicity by utilising a Continuous Hydrothermal Flow Synthesis (CHFS) process as an efficient cutting tool in combination with calix[4]arene tetrasulfonic acid (SCX4) as an effective particle size limiting agent.

The transient critical heat fluxes (CHFs) were measured for water flowing in a small vertical tube with exponentially increasing heat inputs. A stainless steel tube (SUS 304) with an inner diameter of 1.0 mm and a length of 47.4 mm was used as a test tube, which was mounted vertically in the experimental water loop. In the experiment, the upward flow velocity ranged from 9.4 to 13.4 m/s and the inlet subcooling ranged from 85 to 145 K. The heat generation rate was exponentially increased as a function of Q0exp(t/τ). The period of the heat generation rate was ranged from 82 ms to 30 s. Experimental results indicated that the CHFs increased with decreasing period of heat generation rates and increasing flow velocity. For shorter periods of the heat generation rate, the CHFs were significantly higher. The CHFs were affected by the period of the heat generation rate and flow velocities. The empirical correlations of the transient CHFs for the small tube were obtained based on the experimental data.

Silicon-doped zinc oxide, Zn1−xSixOy, transparent conducting oxide nanoparticles were prepared using a laboratory scale (production rate of 60 g h−1) continuous hydrothermal flow synthesis (CHFS) process in the dopant range 0.25 to 3.0 at% Si. The resistivity of the materials was assessed as pressed heat-treated pellets, revealing that the sample with the lowest resistivity (3.5 × 10−2 Ω cm) was the 0.25 at% Si doped ZnO sample. The synthesis of this optimum composition was then scaled up to 350 g h−1 using a larger pilot plant CHFS process. Spin coating of a slurry of the resulting nanopowder made on the pilot plant, followed by an appropriate heat-treatment, produced a thin film with an optical transmission >80% and a low resistivity of 2.4 × 10−3 Ω cm, with a carrier concentration of 1.02 × 1020 cm−3 and a mobility of 11 cm2 V−1 s−1. This is a factor of almost twenty times improvement in the resistivity versus the analogous pressed, heat-treated pellet.

Systemic sclerosis (SSc) is a chronic autoimmune disease causing complex hand disability. A reliable tool for hand function assessment in SSc is the Cochin Hand Functional Disability Scale (CHFS). More recently, a short-form CHFS of 6 items (CHFS-6) has been developed. Objectives To validate the CHFS and the new CHFS-6 in Romanian patients with SSc. Patients and methods Consecutive patients with SSc who completed the CHFS were included. All patients were assessed according to the recommendations of the European Scleroderma and Research Trials and also completed the Scleroderma Health Assessment Questionnaire and the Hand Mobility in Scleroderma questionnaire. Finger range-of-motion distances were measured. Results Seventy patients, 63 female and 7 male patients (age median, 53.0 years; interquartile range [IQR], 21.0 years), were included. Twenty seven had diffuse cutaneous involvement (dcSSc). Median CHFS and CHFS-6 at baseline were 25.0 (IQR, 37.0) and 8.0 (IQR, 13.0), respectively.The internal consistency (Cronbach α = 0.96, respectively, 0.90, in all 70 patients) and test-retest reliability (intraclass correlation coefficient = 0.98 for both, in 38 patients) of both CHFS and CHFS-6 were excellent. The CHFS-6 had a very high correlation with the CHFS. There were moderate to good correlations with Hand Mobility in Scleroderma, Scleroderma Health Assessment Questionnaire, and the anthropometric measurements (construct validity). In patients with early dcSSc with a second evaluation, we found good to moderate sensitivity to change (standardized response mean of 0.8 and effect size of 0.4 for CHFS, and standardized response mean of 1.1 and effect size of 0.6 for CHFS-6). Conclusions The CHFS and CHFS-6 are valid and easy-to-use tools for hand involvement in SSc, which can be used in clinical or research setting.

Condylar head fractures (CHFs) are increasingly treated by open reduction and internal fixation (ORIF). However, there are no reports on the three-dimensional postoperative volumetric transformation of the condyle, especially with regard to fragmented cases. Protruding hardware can lead to severe complications, so the goal of this study was to examine the amount of condylar bony resorption occurring after ORIF.Included were surgically treated CHFs with eligible cone beam computer tomography (CBCT) datasets immediately after ORIF (T1) and after implant removal (T2), plus fractures of the condylar neck and base as a reference. 2D vertical and 3D volume changes of the condylar head after ORIF of CHFs were evaluated by CBCT datasets transformed into 3D models for 3D volumetric assessment using Slicer freeware.Among a total of 50 fractures (38 patients), including 41 CHFs (ORIF with titanium positional screws, including 15 minor and 12 major fragmented cases) plus nine extracapsular fractures (eight upper neck and one base fracture), postoperative condylar volume decreased by a mean of 0.27 cm³ (median 0.25 cm³; SD 0.23 cm³) or 16% (median 14%; SD 11%). Major fragmented CHFs showed significantly higher resorption rates (p 0.001, range 8-42%). Age correlated with a decrease in condylar volume (mean 2.4% per 10 years of age, (p = 0.011). No significant correlation could be established between loss of condylar volume and fracture localization. A protrusion of metallic implants was seen in 20% of the assessed cases.Due to substantial volume changes of the condylar head occurring after ORIF, protrusion of implants (both metallic and resorbable) needs to be taken into consideration. An early removal of metallic ostheosyntesis material (around 4 months after ORIF) is strongly recommended to avoid adverse short- and long-term effects.

Continuous hydrothermal flow synthesis (CHFS) is a facile, upscalable and cost-efficient synthetic method enabling the nanostructuring of advanced functional materials in steady conditions, i.e. not in batch synthesis. In this paper, we use CHFS to crystallize NiCo- and NiFe-hydroxides in water solution with 2D nanofeatures. By tuning the synthetic parameters, we disclose the key role of the cation redox chemistry in the transition between two competitive phases: from 2D-nanoplatelets of brucite to layered double hydroxides (LDH). For controlling the precipitation of different Ni, Fe, Co-hydroxide phases, we propose the combined use of an oxidizing (H2O2) and a complexing (NH3) agent. At temperatures as low as 80 {\deg}C, the presence of H2O2 and a low concentration of NH3 favour the Ni2+/Co3+ over Ni2+/Co2+ oxidation states, shifting the product structure from brucite phase (temperatures > 80 {\deg}C) to LDH. Conversely, for the NiFe-hydroxides the transition from LDH (temperatures < 80 {\deg}C) to brucite phase (temperatures > 80 {\deg}C) is controlled by the reaction temperature only. Due to the high stability of Fe3+, the synthesis of NiFe products by CHFS does not require oxidizing and complexing agents, resulting in a robust process for large-scale production., Comment: Tables and Figures at the end of the manuscript

Direct cooling with inert and hazards free dielectric liquids may well become the method of choice for thermal management of future electronic systems. Owing to the efficiency of phase-change process and the ease of natural circulation, pool boiling is of great interest for this application. The present review consolidates a large number of pool boiling experimental data for dielectric and other highly wetting liquids subject to engineered surfaces with elaborating the related augmentation mechanisms. Potential micro/nano engineered surfaces are categorized into one-dimensional (either CHF or HTC enhancing) and two-dimensional (both CHF and HTC) enhancement surfaces. The enhancement mechanisms along with the bubble dynamics of these enhanced surfaces are discussed briefly. Furthermore, a general classification of electronics coolants (dielectric, non-dielectric, and nanofluids) along with their thermophysical properties is made; especially the problems associated with the dielectric liquids are discussed. Finally, the potential mechanisms for higher HTCs and CHFs are identified.

This article reviews the recent research on the effect of micro- and nanomodified surfaces and coatings on heat-transfer enhancement and critical heat fluxes (CHFs) at boiling. The first part contains a detailed review of papers devoted to investigation of boiling heat transfer and crisis phenomena in nanofluids. The interest in this field is caused by a significant increase in the CHF value at boiling of nanofluid due to the sedimentation of nanoparticles and altered wettability and porosity of heat-releasing surfaces. Possible mechanisms of the increase in CHF and the main disadvantages of using nanofluids in practical applications are discussed. The second part is devoted to various techniques that are used to create micro- and nanostructured heat-exchange surfaces and to research the effect of modified heaters on boiling performance.

Objective: To develop and validate a short form of the Cochin Hand Function Scale (CHFS), which measures hand disability, for use in systemic sclerosis, using objective criteria and reproducible techniques. Methods: Responses on the 18-item CHFS were obtained from English-speaking patients enrolled in the Scleroderma Patient-Centered Intervention Network Cohort. CHFS unidimensionality was verified using confirmatory factor analysis, and an item response theory model was fit to CHFS items. Optimal test assembly (OTA) methods identified a maximally precise short form for each possible form length between 1 and 17 items. The final short form selected was the form with the least number of items that maintained statistically equivalent convergent validity, compared to the full-length CHFS, with the Health Assessment Questionnaire (HAQ) disability index (DI) and the physical function domain of the 29-item Patient-Reported Outcomes Measurement Information System (PROMIS-29). Results: There were 601 patients included. A 6-item short form of the CHFS (CHFS-6) was selected. The CHFS-6 had a Cronbach's alpha of 0.93. Correlations of the CHFS-6 summed score with HAQ DI (r = 0.79) and PROMIS-29 physical function (r = -0.54) were statistically equivalent to the CHFS (r = 0.81 and r = -0.56). The correlation with the full CHFS was high (r = 0.98). Conclusion: The OTA procedure generated a valid short form of the CHFS with minimal loss of information compared to the full-length form. The OTA method used was based on objective, prespecified criteria, but should be further studied for viability as a general procedure for shortening patient-reported outcome measures in health research.

A series of LiMn1–x–yFexVyPO4 (LMFVP) nanomaterials have been synthesized using a pilot-scale continuous hydrothermal synthesis process (CHFS) and evaluated as high voltage cathodes in Li-ion batteries at a production rate of 0.25 kg h–1. The rapid synthesis and screening approach has allowed the specific capacity of the high Mn content olivines to be optimized, particularly at high discharge rates. Consistent and gradual changes in the structure and performance are observed across the compositional region under investigation; the doping of Fe at 20 at% (with respect to Mn) into lithium manganese phosphate, rather than V or indeed codoping of Fe and V, gives the best balance of high capacity and high rate performance.

Micro/nanotextured coatings have enabled the manipulation of thermal characteristics in pool boiling heat transfer such as the heat transfer coefficient (HTC) and critical heat flux (CHF) because of the ability to optimize bubble formations and departures. However, fabricating such coatings on substrates involves high cost-bulky setup, and is limited by the materials and adhesion properties. Herein, we report layer-by-layer (LbL)-assembled polyethylenimine (PEI)-multi-walled carbon nanotube (MWCNTs) coatings on stainless steel (SS316) to enhance HTC and CHF in pool boiling heat transfer. LbL-assembled PEI-MWCNTs coatings (10, 20, 40 bi-layers) on SS316 were fabricated, whereas bare SS316 substrate and vacuum-filtered MWCNTs coating were prepared as controls. Because of the nano-cavities and the inner-nanoporous structures, LbL coatings showed significant enhancement of HTCs and CHFs compared to bare SS316. Furthermore, denser networks of MWCNTs due to electrostatic bonding and hydrophilic nature of PEI in the LbL coatings could enhance the HTCs and CHFs compared to vacuum-filtered MWCNTs coating. LbL-assembled PEI-MWCNTs of 20 bi-layers showed the highest improvement in HTC, whereas the 40 bi-layers coatings achieved the best enhancement ratio of CHF, (∼147%). Further development of the LbL-assembled coatings on metal surfaces would enable potential applications for thermal management, from micro/nanoscale platforms to macroscale systems.

Depression is a major mental disorder, and is currently recognized as the second-leading cause of disability worldwide. However, the therapeutic effect of antidepressants remains unsatisfactory. For centuries, Chinese herbal formulas (CHFs) have been widely used in the treatment of depression, achieving better therapeutic effects than placebo and having fewer side effects than conventional antidepressants. Here, we review the ethnopharmacology, phytochemistry, and pharmacology studies of nine common CHFs: "banxia houpo" decoction, "chaihu shugansan", "ganmaidazao" decoction, "kaixinsan", "shuganjieyu" capsules, "sinisan", "wuling" capsules, "xiaoyaosan", and "yueju". Eight clinical trials and seven meta-analyses have supported the theory that CHFs are effective treatments for depression, decreasing Hamilton Depression Scale scores and showing few adverse effects. Evidence from 75 preclinical studies has also elucidated the multitarget and multipathway mechanisms underlying the antidepressant effect of the nine CHFs. Decoctions, capsules, and pills all showed antidepressant effects, ranked in descending order of efficacy. According to traditional Chinese medicine theory, these CHFs have flexible compatibility and mainly act by soothing the liver and relieving depression. This review highlights the effective treatment choices and candidate compounds for patients, practitioners, and researchers in the field of traditional Chinese medicine. In summary, the current evidence supports the efficacy of CHFs in the treatment of depression, but additional large-scale randomized controlled clinical trials and sophisticated pharmacology studies should be performed.

Highly monodispersed CuO nanoparticles (NPs) were synthesized via continuous hydrothermal flow synthesis (CHFS) and then tested as catalysts for CO2 hydrogenation. The catalytic behavior of unsupported 11 nm sized nanoparticles from the same batch was characterized by diffuse reflectance infrared fourier transform spectroscopy (DRIFTS), extended X-ray absorption fine structure (EXAFS), X-ray diffraction (XRD), and catalytic testing, under CO2/H2 in the temperature range 25–500 °C in consistent experimental conditions. This was done to highlight the relationship among structural evolution, surface products, and reaction yields; the experimental results were compared with modeling predictions based on density functional theory (DFT) simulations of the CuO system. In situ DRIFTS revealed the formation of surface formate species at temperatures as low as 70 °C. DFT calculations of CO2 hydrogenation on the CuO surface suggested that hydrogenation reduced the CuO surface to Cu2O, which facilitated the formation of formate. In situ EXAFS supported a strong correlation between the Cu2O phase fraction and the formate peak intensity, with the maxima corresponding to where Cu2O was the only detectable phase at 170 °C, before the onset of reduction to Cu at 190 °C. The concurrent phase and crystallite size evolution were monitored by in situ XRD, which suggested that the CuO NPs were stable in size before the onset of reduction, with smaller Cu2O crystallites being observed from 130 °C. Further reduction to Cu from 190 °C was followed by a rapid decrease of surface formate and the detection of adsorbed CO from 250 °C; these results are in agreement with heterogeneous catalytic tests where surface CO was observed over the same temperature range. Furthermore, CH4 was detected in correspondence with the decomposition of formate and formation of the Cu phase, with a maximum conversion rate of 2.8% measured at 470 °C (on completely reduced copper), supporting the indication of independent reaction pathways for the conversion of CO2 to CH4 and CO that was suggested by catalytic tests. The resulting Cu NPs had a final crystallite size of ca. 44 nm at 500 °C and retained a significantly active surface.

A pilot plant scale continuous hydrothermal flow synthesis (CHFS) process was used to control the crystallite size (and surface area) for nano-TiO2 in the range ca. 5–18 nm. In CHFS, a room temperature solution of titanium oxysulfate (and boric acid) was mixed in flow with a feed of potassium hydroxide solution (at 24.1 MPa), and then this combined stream was mixed with a flow of superheated water (at 400 °C and 24.1 MPa) in a confined jet mixer. Nano-TiO2 particles were formed instantly and then cooled inline before being collected as a slurry from the exit of the process. It was observed that the boric acid concentration in the precursor feed affected reaction pH, which in turn, determined the average crystallite size of the nano-TiO2; as the pH increased, larger crystallites were obtained. The nanomaterials were evaluated in a sacrificial photocatalytic water splitting system (hydrogen evolution), and it was found that TiO2 prepared under mildly acidic conditions, yielded the highest photoactivity.

As an important part of culture, consumption concept can not only influence people’s attitude about worth and wealth, but also their economical behavior and financial decisions. Based on CHFS2011 database, this paper analyzes the relationship between consumption concept and people’s choice of financial assets. The empirical results of this paper show that those who hold forward and positive consumption concept are more willing to hold risk assets than those who hold traditional and conservative consumption concept.

Green fluorescent graphene quantum dots (GQD) have been synthesized via hydrothermal fragmentation using a continuous hydrothermal flow synthesis (CHFS) process as a single, rapid and environmentally benign method. This is in the presence of p-phosphonic acid calix[4]arene which enhances the optical properties of the graphene quantum dots through surface functionalization, with photoluminescence quantum yields of up to 4.5%. Potential environmental impact of a lab-scale supercritical CHFS process compared with that of conventional batch processing of GQDs has been assessed using the method of the International Reference Life Cycle Data System (ILCD).

Objectives: Our aim was to describe the burden of early dcSSc in terms of disability, fatigue and pain in the European Scleroderma Observational Study cohort, and to explore associated clinical features.Methods: Patients completed questionnaires at study entry, 12 and 24 months, including the HAQ disability index (HAQ-DI), the Cochin Hand Function Scale (CHFS), the Functional Assessment of Chronic Illness Therapy-fatigue and the Short Form 36 (SF36). Associates examined included the modified Rodnan skin score (mRSS), current digital ulcers and internal organ involvement. Correlations between 12-month changes were also examined.Results: The 326 patients recruited (median disease duration 11.9 months) displayed high levels of disability [mean (S.D.) HAQ-DI 1.1 (0.83)], with ‘grip’ and ‘activity’ being most affected. Of the 18 activities assessed in the CHFS, those involving fine finger movements were most affected. High HAQ-DI and CHFS scores were both associated with high mRSS (ρ = 0.34, P < 0.0001 and ρ = 0.35, P < 0.0001, respectively). HAQ-DI was higher in patients with digital ulcers (P = 0.004), pulmonary fibrosis (P = 0.005), cardiac (P = 0.005) and muscle involvement (P = 0.002). As anticipated, HAQ-DI, CHFS, the Functional Assessment of Chronic Illness Therapy and SF36 scores were all highly correlated, in particular the HAQ-DI with the CHFS (ρ = 0.84, P < 0.0001). Worsening HAQ-DI over 12 months was strongly associated with increasing mRSS (ρ = 0.40, P < 0.0001), decreasing hand function (ρ = 0.57, P < 0.0001) and increasing fatigue (ρ = −0.53, P < 0.0001).Conclusion: The European Scleroderma Observational Study highlights the burden of disability in early dcSSc, with high levels of disability and fatigue, associating with the degree of skin thickening (mRSS). Impaired hand function is a major contributor to overall disability.

Continuous hydrothermal flow synthesis (CHFS) has been employed as rapid and cleaner route for the synthesis of a novel, highly efficient graphene-inorganic heterogeneous catalyst, denoted as Ce–La–Zr–GO nanocomposite. The catalyst was used for the direct synthesis of propylene carbonate (PC) from the cycloaddition of carbon dioxide (CO2) and propylene oxide (PO) in the absence of any organic solvents. Ce–Zr–La–GO nanocomposite was synthesized from pre-mixed aqueous solution of cerium, lanthanum, zirconium nitrate and GO (synthesized via conventional Hummers method) under alkaline conditions using the CHFS reactor. The resulting nanocomposite catalyst was heat-treated at various temperatures (773, 973 and 1173 K) and their catalytic properties were assessed. The as-prepared and the corresponding heat-treated catalysts were characterized using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD) and Brunauer–Emmett–Teller (BET) surface area measurements. Effect of various parameters such as heat-treatment temperature, catalyst loading, CO2 pressure, reaction time and temperature was systematically studied to determine the optimum reaction conditions. The optimum reaction condition for the direct synthesis of PC was found at 443 K, 70 bar and 10% (w/w) catalyst loading. Catalyst reusability study was also conducted to investigate the long life stability for the synthesis of PC and it was found that the catalyst could be reused several times without losing it catalytic activity. These studies revealed that Ce–Zr–La–GO nanocomposite catalyst showed high catalytic activity as compared to other reported heterogeneous catalysts with the conversion of PO, selectivity and yield of PC.

This paper aims at evaluating trace elements (TEs) removal during biomass cofiring in a fluidised bed pilot plant (1 MWth) equipped with a Catalytic Hybrid Filter System (CHFS), as air pollution control device, which combines electrostatic precipitation (ESP) and fabric filter (FF) in a unique approach to develop a compact but highly efficient system. One biomass (olive tree pruning (OP)) and two different waste materials (municipal refuse derived fuel (RDF) and compost (CO)) were employed in the cofiring tests, to evaluate the impact of the fuel in the process. TEs control through the CHFS as well as the effect of this system on mercury speciation, were evaluated. In addition, different factors which may be involved in TEs retention, such as ash matter composition and fly ash particle size, were investigated. Significant removal efficiency was achieved at the CHFS for most TEs studied, even for the most highly volatile TEs such as Hg and Se (40–60%), Cd (50–70%) and Sb (80–90%). Similar trends for TEs capture were observed for both fuel mixtures, obtaining the highest removal rates for Cu, Pb, Cr and Zn. However the retention of most TEs was significantly affected by the fuel employed, as consequence of the different composition and characteristics of ashes generated in each process. The capture of most TEs was seen to be highly influenced by the calcium content in fly ashes, while TEs of higher volatility were seen to be preferably retained in the finest size particles (

Boiling is commonly used in daily life and is an efficient heat removal method. During pool boiling, the critical heat flux (CHF) establishes the upper limit of efficient heat removal. Although, numerous studies have explored CHF, its exact mechanisms remain ambiguous. The hydrodynamic instability model is the most prominent CHF model, but it fails to explain the evident dependence of CHF on surface properties. The authors proposed modifying the hydrodynamic model to account for how nucleation site density and finite heater size affect the CHF. The experimental CHF values obtained from evaluating various types of surfaces qualitatively agreed with the predictions of the modified hydrodynamic model. This suggests that the CHFs on these surfaces were due to the hydrodynamic limit.

The use of digital forensics tools has become common in typical crime investigations involving computing and communication devices. As with any evidence in criminal investigations, the preservation of digital evidence is of critical importance for the success of the investigation. Cryptographic Hash Functions (CHFs) are used by digital forensic tools to ensure the preservation of digital evidence during the acquisition and analysis of evidence. These tools make the use of the CHFs during the acquisition process to ensure that the created image of the evidence is accurate. The CHFs that are currently in use are serial in nature and can be time consuming when working with the large data sets. We propose a new parallel CHF transformation to speed up the image creation process by a factor of 6.5 over existing methods. We discuss the use of the parallel algorithm in the image creation process and compare the results with the existing sequential methods.

Two-fluid model coupled with improved RPI wall boiling model (CHF model) was employed to investigate the departure from nuclear boiling (DNB) phenomena in vertical pipes under extremely high heat flux by using FLUENT 14.5 code. The distributions of temperature before and after DNB and the critical heat fluxes (CHF) at corresponding DNB points were obtained. The maximum deviation of predicted CHFs with experimental data was less than 15.0%. The results proved that two-fluid model coupled with CHF model was qualified to predict CHF accurately. This work can be referred when one predicts CHF in complicated geometry by CFD methodology.

This study investigated the effects of electrical stimulation with theta burst stimulation (eTBS) on seizure suppression. Optimal parameters of eTBS were determined through open-loop stimulation experiments and then implemented in a close-loop seizure control system. For the experiments, 4-aminopyridine (4-AP) was injected into the right hippocampus of Sprague–Dawley rats to induce an acute seizure. eTBS was applied on the ventral hippocampal commissure and the effects of eTBS with different combinations of burst frequency and number of pulses per burst were analyzed in terms of seizure suppression. A closed-loop seizure control system was then implemented based on optimal eTBS parameters. The efficiency of the closed-loop eTBS was evaluated and compared to that of high frequency stimulation. The results show that eTBS induced global suppression in the hippocampus and this was sustained even after the application of eTBS. The optimal parameter of eTBS in the open-loop stimulation experiments was a burst frequency at 100 Hz with nine pulses in a burst. The eTBS integrated with the on–off control law yielded less actions and cumulative delivered charge, but induced longer after-effects of seizure suppression compared to continuous high frequency stimulation (cHFS). To conclude, eTBS has suppressive effects on 4-AP induced seizure. A closed-loop eTBS system provides a more effective way of suppressing seizure and requires less effort compared to cHFS. eTBS may be a novel stimulation protocol for effective seizure control.

Being the second largest economy and the host of the largest population in the world, China, with its unique success, has challenged traditional economic wisdom in many ways. For a long time, resea...

Nanomaterials are at the leading edge of the emerging field of nanotechnology. Their unique and tunable size-dependent properties (in the range 1-100 nm) make these materials indispensable in many modern technological applications. In this Review, we summarize the state-of-art in the manufacture and applications of inorganic nanoparticles made using continuous hydrothermal flow synthesis (CHFS) processes. First, we introduce ideal requirements of any flow process for nanoceramics production, outline different approaches to CHFS, and introduce the pertinent properties of supercritical water and issues around mixing in flow, to generate nanoparticles. This Review then gives comprehensive coverage of the current application space for CHFS-made nanomaterials including optical, healthcare, electronics (including sensors, information, and communication technologies), catalysis, devices (including energy harvesting/conversion/fuels), and energy storage applications. Thereafter, topics of precursor chemistry and products, as well as materials or structures, are discussed (surface-functionalized hybrids, nanocomposites, nanograined coatings and monoliths, and metal-organic frameworks). Later, this Review focuses on some of the key apparatus innovations in the field, such as in situ flow/rapid heating systems (to investigate kinetics and mechanisms), approaches to high throughput flow syntheses (for nanomaterials discovery), as well as recent developments in scale-up of hydrothermal flow processes. Finally, this Review covers environmental considerations, future directions and capabilities, along with the conclusions and outlook.

International audience; Computer-Aided Diagnosis (CAD) of Alzheimer's disease (AD) has drawn the attention of computer vision research community over the last few years. Several attempts have been made to adapt pattern recognition approaches to specific neuroimaging data such as Structural MRI (sMRI) for early AD diagnosis. One strategy is to boost the discrimination power of such approaches by integrating complementary imaging modalities in a single learning framework. Diffusion Tensor Imaging (DTI) is a new and promising modality giving complementary information to the anatomical MRI. However, including relevant DTI information from such modality is a challenging problem. In this paper, we propose to extract local image-derived biomarkers from DTI and sMRI to construct multimodal AD signatures. To assess the relevance of such modalities as well as to optimize the classifier, we integrate complementary information using a Multiple Kernel Learning (MKL) framework for AD subjects recognition. To evaluate our method, we perform experiments on a subset from the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset. Both T1-weighted MRI and Mean Diffusivity (MD) maps from the DTI modality of 45 AD patients, 52 Normal Control (NC) and 58 Mild Cognitive Impairment (MCI) subjects have been used. The obtained results indicate that our multimodal approach yields significant improvement in accuracy over using each single modality independently. The classification accuracies obtained by the proposed method are 90.2%, 79.42% and 76.63% for respectively AD vs. NC, MCI vs. NC and AD vs. MCI binary classification problems. For the MCI classification problem, the proposed fusion framework leads to an average increase about at least 9% for the accuracy, 5% for the specificity and 15% for the sensitivity.

This paper reported the feasibility of a supercritical water synthesis route (referred as CHFS) in the application of selective catalytic reduction (SCR) of NO with NH3. A series of well-reported CexTiO2 SCR catalysts were synthesized and then subjected to a range of characterizations (e.g. XRD, XPS, H2-TPR, HADDF, etc.). Experimental results revealed that the unusual and rapid crystallizing environment of the CHFS route had resulted in a highly dispersed CeO2 and a strong metal-support interaction (SMSI) for CexTiO2 catalysts, which promoted the enriched surface oxygen vacancies and facilitated the formation of NO2 and nitrite species over the catalyst surface, effectively enhancing their SCR performances. Amongst the developed CexTiO2 catalysts, Ce0.25TiO2 revealed the highest SCR activity with more than 90% NO conversion being achieved in a broad temperature range of 240–440 °C. Such broad temperature window was proven due to the SMSI, which lowered the NH3 oxidation ability of CeO2, retaining the effective utilization of NH3 throughout the SCR process. The work conducted herein demonstrates the feasibility of the CHFS route in the syntheses of SMSI catalysts for SCR application and also explores the SCR reaction mechanism over the well-reported CexTiO2 catalysts. We expected that this work could shed some lights on the development of feasible preparative routes for the syntheses of advanced SMSI catalysts for SCR application.

We used a heating surface composed of a hydrophilic substrate with hydrophobic dots to characterize the effect of spatially-different surface characteristics on critical heat flux (CHF) and nucleate boiling. To ascertain important surface factors that control CHF and boiling on heterogeneous wetting surfaces, we adjusted the hydrophobic dot diameter and the relative pitch between adjacent dots. Based on the dynamics of bubbles on hydrophobic dots, we analyze the trend of CHF on differently-fabricated heterogeneous wetting surfaces. CHFs on heterogeneous wetting surfaces were strongly dependent on ratio R of the area covered by hydrophobic dots to the heated area, but independent on the diameter of hydrophobic dots and the pitch distance. The improvement of boiling heat transfer (BHT) varied according to the conditions, and appeared to be related to the diameter, pitch distance and the number of hydrophobic dots, but the effect of R on BHT was negligible. Based on this study, we propose optimized conditions of a hydrophobic patterned surface. To sustain high CHF of a hydrophilic surface and high BHT of a hydrophobic surface, numerous micron-size hydrophobic dots should be fabricated with small R .

In situ high-energy synchrotron X-ray diffraction, a non-destructive synchrotron-based technique was employed to probe inside the steel tubing of a continuous hydrothermal flow synthesis (CHFS) mixer to spatially map, for the first time, the superheated water crystallisation of nanocrystalline ceria (CeO2) at three different (superheated-water) temperatures representing three unique chemical environments within the reactor. Rapid hydrothermal co-precipitation at the three selected temperatures led to similarly sized ceria nanoparticles ranging from 3 to 7 nm. 2D maps of CeO2 formation were constructed from the intensity and corresponding full width at half maximum (FWHM) values of the two most intense ceria reflections (111) and (002) for all three water inlet temperatures (350, 400 and 450 °C at 24 MPa) and subsequent changes in the particle size distribution were analysed. The accompanying high-resolution transmission electron microscopy (HRTEM) and tomographic particle size maps have confirmed that the mean ceria particle size slightly increases with temperature. This X-ray tomographic imaging study amounted to a formidable technical and engineering challenge, nevertheless one that has been met; this represents a significant achievement in imaging science, given the dynamic nature and hostile environment of a working CHFS reactor.

A confined jet reactor (mixer) is presented as a novel solution for the scalable continuous hydrothermal flow synthesis (CHFS) of nanoceramics. In CHFS, nanoceramics are formed upon mixing of two streams consisting of an aqueous metal salt solution at room temperature with a flow of less dense supercritical water (at 240 bar and 450 °C). Upon mixing, hydrolysis and dehydration occurs, resulting in the particles being formed in a continuous manner. The confined jet mixer used herein overcomes previous designs of mixers that can accumulate material internally and block. A method for scaling up the jet mixer (reactor) is described, to determine the size of jet mixer (internal mixer diameter 13.5 mm) prior to its use in a newly commissioned pilot plant designed to process flow rates 40 times greater than the equivalent laboratory-scale process (internal mixer diameter 4.6 mm). It was confirmed that the pilot plant scale mixer allowed safe and continuous operation with no blockages at much higher concentration...

In this study, a smooth flat surface, low fin, Turbo-B, and Thermoexcel-E surfaces are used to examine the effect of the flow velocity on the pool boiling heat transfer coefficients (HTCs) and critical heat fluxes (CHFs). HTCs and CHFs are measured on a smooth square heater of 9.53 × 9.53 mm2 at 60°C in a pool of pure water at various fluid velocities of 0, 0.1, 0.15, and 0.2 m/s. Test results show that for all surfaces, CHFs obtained with flow are higher than those obtained without flow. CHFs of the low fin surface are higher than those of the Turbo-B and Thermoexcel-E surfaces due largely to the increase in surface area and sufficient fin spaces for the easy removal of bubbles. CHFs of the low fin surface show even 5 times higher CHFs as compared to the plain surface. On the other hand, both Turbo-B and Thermoexcel-E surfaces do not show satisfactory results because their pore sizes are too small and water bubbles easily cover them. At low heat fluxes of less than 50 kW/m2, HTCs increase as the flow velocity increases for all surfaces. In conclusion, a low fin geometry is good for application to steam generators in nuclear power plants.

Objective To assess changes over time and responsiveness of the Cochin Hand Function Scale (CHFS) and Mouth Handicap In Systemic Sclerosis (MHISS) scale in patients with systemic sclerosis (SSc). Design This was a prospective longitudinal study. Participants Participants were drawn from a convenience sample of individuals with SSc, who were attending the annual Congress of the Association des Sclerodermiques de France, the French SSc patients' association. Methods Participants were evaluated twice by the CHFS, MHISS scale, Health Assessment Questionnaire, McMaster-Toronto Arthritis Patient Preference Disability Questionnaire, and other outcome measures. Differences in measures over time were evaluated using the Wilcoxon signed rank test. Responsiveness was assessed by the effect size and standardized response mean. Nonparametric Spearman rank correlation (r) was used to assess correlation between outcome measures. Results Forty-nine patients were assessed. The CHFS and MHISS scores worsened over time (mean [SD] differences 2.7 [10.7], P = 0.08, and 3.5 [9.8], P = 0.14, respectively). The CHFS effect size and standardized response mean values were -0.16 and -0.24, respectively, and MHISS values were -0.53 and -0.52, respectively. The correlation between change in the CHFS score and change in Health Assessment Questionnaire and McMaster-Toronto Arthritis Patient Preference Disability Questionnaire scores was fair to moderate, whereas changes in MHISS score were poorly or not correlated to other measures. For patients considering their state deteriorated, the MHISS scale was the most responsive instrument. Conclusions The CHFS and MHISS scores may be useful in detecting changes in location-specific limitations in activity for SSc patients.

Demonstrated herein is a single rapid approach employed for synthesis of Ag–graphene nanocomposites, with excellent antibacterial properties and low cytotoxicity, by utilizing a continuous hydrothermal flow synthesis (CHFS) process in combination with p-hexasulfonic acid calix[6]arene (SCX6) as an effective particle stabilizer. The nanocomposites showed high activity against E. coli (Gram-negative) and S. aureus (Gram-positive) bacteria. The materials were characterized using a range of techniques including transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, UV–vis spectrophotometry, FT-IR, and X-ray powder diffraction (XRD). This rapid, single step synthetic approach not only provides a facile means of enabling and controlling graphene reduction (under alkaline conditions) but also offers an optimal route for homogeneously producing and depositing highly crystalline Ag nanostructures into reduced graphene oxide substrate.

Pool boiling of saturated water on plain Si surfaces and surfaces covered with a dense array of Si nano- wires (SiNWs) has been studied. Measured CHF and heat transfer coefficient (HTC) values of about 223 ± 5.61 W/cm 2 and 9 ± 1.60 W/cm 2 K, respectively, on the nanowire array-coated surface are among the highest reported in boiling heat transfer. Meanwhile, the CHFs on both nanowire-coated and Plain Si surfaces show a similar heater size dependence - the CHF increases as heater size decreases. The mea- sured CHFs on both types of surfaces are approximately following the prediction of the hydrodynamic theory assuming the Helmholtz wavelength equal to the corresponded heater length. It suggests that the CHFs on both types of surfaces might be limited by pool hydrodynamics.

Continuous hydrothermal flow synthesis (CHFS) technology has shown great advantages in nanomaterial formulation compared with other synthesis methods. CHFS uses a flow of supercritical water as a reagent that reacts with a flow of metal salts to produce nanoparticles in a reactor. The process uses no organic solvent, therefore is green, and has good controllability due to being in continuous operational mode. Experimental studies have shown that very high quality nanoceramics can be made in minutes rather than days. This paper describes simulation studies of the reaction and precipitation in a CHFS process using population balance modelling technique. Models for reaction kinetics, thermodynamics and nucleation are presented. Particle surface growth mechanism and particle aggregation effects have also been taken into consideration in the population balance models. System kinetics and the dynamic evolution of particle size distribution under supercritical conditions were simulated. The effects of temperature, aggregation and growth rate on particle size distribution were also investigated.

Metal oxide nanoparticles are promising materials in applications for fuel cells, gas sensors and fine chemical catalysis. Their functionality depends excessively on composition, structure as well as synthesis and processing conditions. Continuous hydrothermal flow synthesis (CHFS) reactors are an effective technology to make nanoceramics. In order to increase sample throughput of CHFS, a manual high-throughput continuous hydrothermal (HiTCH) flow synthesis process capable of formulating scores of samples per day was developed. More recently, a fully automated nanoceramics synthesis platform called RAMSI (rapid automated synthesis instrument) based on the HiTCH synthesis technology was developed. When large numbers of nanoceramics are made and formulated into appropriate libraries, automated analytical instruments can be used to allow collection of a large amount of useful data. This paper describes the information flow management system of RAMSI (as well as CHFS) and the data mining system for supporting discovery, QSAR (quantitative structure–activity relationship) modeling and DoE (design of experiments). Case studies demonstrating the use of the high-throughput data mining system are presented. These include clustering of Raman spectra, interpretation of X-ray diffraction (XRD) measurements, and QSAR model building linking XRD data and photocatalytic properties. A genetic algorithm method for DoE is also presented that can guide the experiments to search optimal XRD patterns.

Nanosized Ce 0.6 Zr 0.3 La 0.05 Y 0.05 O 2− δ /γ-Al 2 O 3 (CZA) composite supports were prepared in one step using a novel continuous hydrothermal flow synthesis (CHFS) route and a conventional co-precipitation route, followed by 10 h heat-treatments at 1000 °C in air (to simulate accelerated ageing). HAADF STEM and HR-TEM results indicated that the sample made via CHFS route (i.e., simultaneous co-precipitation in supercritical water, denoted as sc-CZA) had homogenously dispersed CZ particles on alumina support whilst that made via conventional co-precipitation route (denoted as co-CZA sample) had a strong segregation between CZ and alumina. As a consequence of these structural and morphological properties, better sintering behaviors upon accelerated ageing and lesser grain growth of CZ particles were obtained. The sc-CZA sample was then used as supports for syntheses of three-way catalysts (TWCs), in which Pd active species were added via either directly co-precipitating (in the CHFS reactor) or simply wet impregnating Pd 2+ onto the support to form composite nanocatalysts. Catalytic measurements revealed that the former had yielded a significantly higher three-way catalytic activity than the latter, attributing to its much higher dispersion of Pd species and stronger interaction between Pd and CZA support.

Herein, we report the rapid single step hydrothermal synthesis of phase pure Bi2MoO6 (koechlinite) and Bi2Mo3O12, via a continuous hydrothermal flow synthesis (CHFS) reactor, which uses supercritical water of 375-450 degrees C at a pressure of 24.1 MPa as a crystallising medium. The product being obtained as highly crystalline nano-materials with high surface area. Simple variation in synthesis condition and appropriate solution stoichiometry were shown to be sufficient to select the phase of the product. The materials synthesised showed significant photcatalytic activity towards the decolourisation of methylene blue in comparison to a commercial gold standard photocatalyst. (c) 2010 Elsevier Masson SAS. All rights reserved.

Accepted: 2010-04-12, 資料番号: SA1001049000

BACKGROUND: Nano-sized titanium dioxide has potential as a photocatalyst, and doped variants may have different photocatalytic properties. Nano-titanias with a wide range of dopants and compositions can be prepared using continuous hydrothermal flow synthesis (CHFS), but when many samples are made, a large-scale screening test is required to investigate their properties. A range of doped nano-titanias were prepared using a CHFS route, and investigated as powders using a range of photocatalytic test methods. These tests included decolourization of methylene blue (in the presence of oxygen), partial oxidation of a simple alcohol (propan-2-ol) and the degradation of aqueous solutions of dichloroacetic acid. The practicality of the tests for large-scale screening was considered, and the test results were cross-correlated to see if any of them gave similar ranking for activity of the photocatalysts.RESULTS: Two of the tests, namely DCA degradation and propan-2-ol, gave similar rank ordering for the nanopowders, while the MB decolourization results did not suggest a strong correlation with any other test. The addition of metal dopants was observed to produce varying results between different dopants and tests.CONCLUSIONS: Two of the tests, DCA degradation and MB decolourization in visible light, were recommended for further use as screening tests. (C) 2009 Society of Chemical Industry

A simple theory was developed to elucidate the influence of sinusoidal oscillation of the inlet flow rate on the occurrence of liquid film dryout in an annular two-phase flow regime in a boiling channel. The theory assumes that the critical heat flux (CHF) under an oscillatory condition can be calculated from values in steady states provided that the effect of axial mixing of the liquid film is appropriately considered. The trends of CHFs calculated using a one-dimensional three-fluid model and those experimentally measured under atmospheric pressure were in reasonable agreement with the proposed theory. However, the CHF values measured under oscillatory conditions were usually higher in the experiment than in the numerical simulation, which indicated that axial liquid transport induced by disturbance waves might enhance axial mixing of the liquid film.

Continuous hydrothermal flow synthesis (CHFS) offers a controllable route to the production of nanocrystalline materials. We describe the application of tomographic X-ray methods to image, for the first time, crystallization at the interior of an in operando CHFS reactor. In the experiment, the steady-state formation of nanoparticulate CeO2 was followed: the synthesis proceeds by rapid hydrolysis of cerium ammonium nitrate and hydrothermal coprecipitation in a near/super-critical water environment (T = 340−450 °C, P = 24 MPa). The results identify the location of particle growth with accompanying indications of crystallite size, and also reveal the build-up of material on the reactor wall during long syntheses. The imaging represents a significant achievement in that information of this kind can be gleaned from such an inhospitable environment as that of a CHFS reactor. The novel combination of tomographic angle- and energy-dispersive diffraction employed was particularly appropriate for this in situ stud...

Nanosized TiO2 powder of high surface area was prepared from an aqueous solution of titanium(IV) bis(ammonium lactato) dihydroxide using a continuous hydrothermal flow synthesis (CHFS) reactor which uses superheated water at 400 degrees C and 24.1 MPa as a crystallizing medium. Freeze-dried nano-TiO2 was heat-treated in air over a range of temperatures and then the resulting powders were characterized using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), BET surface area measurement, and Raman spectroscopy. The particle size of the 'as-prepared' TiO2 made using CHFS was ca. 4.8 nm (by HR-TEM), and grew with increasing heat-treatment temperature. It was found that the onset of the anatase-rutile transition of heat-treated nano-TiO2 in air occurred at 500 degrees C and reached 100% rutile at 900 degrees C. The Raman band (E-g) at similar to 150 cm(-1) of anatase (nano-TiO2) softens as the particle size increases with heat-treatment temperature (up to 600 degrees C). The photocatalytic activity of the TiO2 powders for the decolourisation of methylene blue dye was assessed. The effects of nano-TiO2 anatase-rutile phase composition, crystallinity, and crystallite size on the catalytic activity were investigated. (C) 2008 Elsevier B.V. All rights reserved.

Pool boiling CHFs for a highly wetting liquid due to steady state and transient heat input were studied. Boiling heat transfer processes on a platinum cylinder in a pool of ethanol due to exponentially increasing heat inputs, Q=Q0exp(t/τ), ranging from quasi-steadily increasing one to rapidly increasing one with periods, τ were measured for a 1.0-mm diameter horizontal cylinder with different surface roughness of commercially-available or roughly-finished surface cylinders for saturated and subcooled liquid at various pressures. Steady-state CHFs at various pressures gradually increased with an increase in subcooling. It was confirmed that the CHFs for lower subcoolings at every pressure almost show little dependence on surface roughness. However the CHF data for the roughly-finished one in many cases were increased for higher subcoolings over pressures. Typical trends of the CHFs were clarified to three groups corresponding to periods: the 1st, 2nd and 3rd groups of CHF were for longer periods, for shorter and for intermediate ones, respectively. It was clarified that the transient CHFs belonging to the 2nd and 3rd group were significantly affected by the surface roughness of cylinders. It appears that more study on the multi-parametric surface roughness and a wider range of experimental conditions need to be included in the study.