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• The modified energy method evaluated the elastic properties of SWBNNT, and the inversion energy term was considered. • Temperature's impact on BNNT's elastic properties was explored by incorporating it as an independent variable. • MSM and continuum mechanics models are used to evaluate the changes in different bonds, bond angles, and reaction angles. The elastic properties of boron nitride nanotubes (BNNTs) were investigated utilizing an enhanced energy method. By considering small deformations and applying the principle of minimum potential energy, the variations in atomic bonds and bond angles within the nanotube structure were determined. The modified model incorporated the contribution of inversion energy to the overall potential energy of the system, leading to the derivation of analytical expressions for the Young's modulus, shear modulus, and strain energy of both armchair and zigzag BNNTs under varying temperatures. The results indicate that compared to zigzag BNNTs, the impact of inversion energy on the elastic constants of armchair BNNTs is more significant, especially at small diameters (<1 nm). In thermal environment, this study demonstrates that the change in Young's modulus of BNNTs is lower than that of carbon nanotubes (CNTs), confirming the superior thermal stability of BNNTs over CNTs. Furthermore, molecular structure mechanics (MSM) and continuum mechanics models were employed to analyze the strain energy of BNNTs. The effects of different bonds, bond angles, and inversion angles on strain energy were analyzed in a thermal environment, revealing distinct differences between the two types of BNNTs. These findings provide more accurate theoretical guidance for thermal applications based on the stretching of BNNTs. [ABSTRACT FROM AUTHOR]

Bismuth vanadate (BiVO 4) has attracted wide attention as photoanode in water-splitting photoelectrochemical (PEC) devices. However, its catalytic performance is greatly limited by the serious charge recombination on the surface states. Herein, borate modified BiVO 4 plus additional CoPi cocatalyst (B-BVO/CoPi) is developed as photoanode for PEC cell via a simple soaking and electrodeposition process. Based on the electrochemistry tests and material characteristics, the borate groups [B(OH) 4 ] – is able to effectively prevent the charge recombination, while the outer CoPi cocatalyst enhance the activity toward oxygen evolution reaction. Therefore, the designed B-BVO/CoPi photoanode could obtain a high current density of 2.67 mA cm−2 at 1.23 V RHE with an onset potential of 0.29 V RHE , much higher than pristine BiVO 4 (0.78 mA cm−2, 0.52 V RHE). This work may provide a new insight for constructing multifunctional modified photoanodes for efficient solar conversion. [Display omitted] • A facile immersion method was employed to enhance the charge separation efficiency on BiVO 4 photoanode surface. • Synergistic effect of borate groups [(B(OH)-)] and CoPi cocatalyst can facilitate charge transfer in the interface. • The integrated photoanodes well improve photoelectrochemical performance compared to pristine BiVO 4 photoanode. [ABSTRACT FROM AUTHOR]

As an important chemical intermediate, the synthesis process of 1,4-butanediol is still energy-intensive and seriously polluting the environment. It is necessary to study its high efficiency and energy saving. The two step synthesis process of 1,4-butanediol: (1) ethynylation of formaldehyde reaction and separation, (2) hydrogenation of 1,4-butynediol reaction and separation are simulated. A sequential iterative optimization method is used to optimize the whole process of 1,4-butanediol production to obtain the best parameters which achieve the minimum annual total cost. In order to further explore the energy-saving process, the heat integration technology is introduced on the basis of the common process, and the annual total cost of the process is reduced by 28.30%. In addition, the exergy efficiency and environmental impact of common process and heat integration process are compared. The results showed that the exergy efficiency of the heat integration process is increased by 6.67% and the CO 2 , SO 2 and NO X emission is reduced by 32.48%, 32.48% and 62.01% compared with the common process. Through the comprehensive analysis of the economy, exergy and environment of synthesis processes, it has important reference significance for the synthesis of 1,4-butanediol in industry. [ABSTRACT FROM AUTHOR]

To evaluate the performance of different chemical exchange saturation transfer (CEST) metrics for grading gliomas with semiautomatically defined regions of interest (ROIs). Thirty-eight adult subjects were included, including 23 high-grade gliomas and 15 low-grade gliomas confirmed by histopathology. The B0-corrected CEST z-spectra were first calculated with magnetization transfer ratio asymmetry (MTR asym) analysis at frequency offsets of 3.5, 3, 2.5, 2, 1.5, and 1 ppm to obtain the fit-free metrics and subsequently fitted with three Lorentzian functions denoting direct water saturation (DS), amide proton transfer (APT), and combined semisolid magnetization transfer and nuclear Overhauser enhancement (MT & NOE) effects to derive the fit-based metrics. Wilcoxon rank-sum test was performed to determine if a statistically significant difference was present in the CEST metrics between low- and high-grade gliomas. Receiver operating characteristic (ROC) curves were used to evaluate the differentiation of CEST metrics between low- and high-grade gliomas. Pearson correlation coefficients were employed to evaluate the correlations of CEST metrics. For the fit-free metrics, the highest areas under the curve (AUCs) of 0.85, 0.88, and 0.88, corresponding to MTR asym , MTR normref (normalization by the reference scan), and MTR Rex (subtraction of inverse z-spectra), respectively, were obtained at 3 ppm across various frequency offsets. In addition, the AUCs generated from the fit-based metrics (0.88–0.90) were higher than those generated from the fit-free metrics at 3 ppm. The results of this preliminary study indicate that fit-free CEST metrics at 3 ppm are superior to the other frequency offsets for grading human brain gliomas. The fit-based metrics manifested improved differentiation between low- and high-grade gliomas compared to the fit-free CEST metrics. [ABSTRACT FROM AUTHOR]

Implant-related infections are a primary reason for implant failures that affect millions of patients. It is of paramount importance to develop novel implants that possess the dual functions of osteogenesis-promotion and antibacterial activity. The objectives of this study were to: (1) develop novel dual-functional titanium (Ti) implants by combining oxygen non-thermal plasma and covalent bonding of antibacterial organosilicon quaternary ammonium monomers; (2) investigate the physicochemical properties, bioactivity and antibacterial effects of the modified implants for the first time. Surface characteristics of the modified Ti surfaces were tested. Adherence and viability of rat bone marrow-derived stem cells (rBMSCs) on the surface were evaluated. Metabolic activity of biofilm on the surfaces were measured. The stability of the dual-function after 5000 thermal cycles was also evaluated. The presence of chemical bonding between Ti and organosilicon monomers demonstrated covalent immobilization of the antibacterial agents. The water contact angle of the treated Ti surfaces decreased from 70.98 ± 3.68° to 59.86 ± 4.91°. The adhesion and proliferation of rBMSCs on the modified Ti were increased by 40%, compared to control group (P < 0.05). The metabolic level of biofilms on modified Ti were reduced by more than half, compared to control (P < 0.05). The modified Ti implants exhibited cell-promotion and antibacterial stability after thermal cycles. The new dual-functional Ti implant is promising to promote osteogenesis while simultaneously preventing infections. Furthermore, the novel surface modification and processing methods have applicability to enhancing a wide range of other implants to improve bioactivity and combat infections. [Display omitted] • A new long-lasting dual-functional titanium implants was developed. • The novel dual-functional implants have improved hydrophilicity. • The modified Ti implant increased the adhesion and proliferation of cells , and reducing the metabolic level of biofilms. • The dual-functional implants are promising to promote osteogenesis and prevent implant-related infections. [ABSTRACT FROM AUTHOR]

In this work, the stability and transformation of two kinds of TiC with different stoichiometries in Cu–Si melts are studied, respectively. It is found that the near-stoichiometirc TiC with fewer carbon vacancies (designated as TiC x ), such as TiC 0.9 , is relatively stable in Cu–Si melts, while the non-stoichiometric TiC with more carbon vacancies (designated as TiC y ), such as TiC 0.6 , is unstable. And TiC y tends to transform into TiC x . Meanwhile, some Ti element from TiC y will be dissolved into the melts. It is considered that the addition of Si influences the equilibrium between TiC with different stoichiometries and soluble Ti in Cu melts, which results in the transformation of TiC. According to the results, the stoichiometry of TiC must be controlled when it is used as the reinforced phase in Cu–Si alloys. [ABSTRACT FROM AUTHOR]

Increasing interests in carbon dots (CDs) research resulted in the increased production of CDs and the risk to be released into the environment, including surface water and groundwater. To assess the environmental behavior of CDs, the stability of CDs in aqueous solutions were first examined by different environmental conditions, followed by the systematic investigation of the adsorption behaviors of CDs onto Al 2 O 3 surface. Electrostatic interactions were considered as the dominant forces in CDs adsorption onto Al 2 O 3 process, which were further confirmed by controlling experiments as compared with other minerals or oxides, such as montmorillonite, kaolinite and SiO 2 . Theoretical calculations and characterization of Al 2 O 3 /CDs revealed chemisorptions exist in the adsorption process. Our investigation results provided fundamental understanding towards the interaction of CDs with Al 2 O 3 surface, and potential fate of CDs under natural conditions in aquatic environment, as well as in soils and sediments. [ABSTRACT FROM AUTHOR]

Energy consumption of buildings accounts for more than 37.3% of total energy consumption while the proportion of energy-saving buildings is just 5% in China. In this paper, in order to save potential energy, the building envelope retrofitting is considered. An office building in Southern China was selected as a test example for energy consumption characteristics. The base building model was developed by TRNSYS software and validated against the recorded data from the field work in six days out of August-September in 2013. In addition, with a design of numerical simulation, sensitivity analysis was conducted for energy performance of building envelope retrofitting; six envelope parameters were analyzed for assessing the thermal responses. Results show that significant energy savings are obtained for the thermal transmittance (U-value) of exterior walls, infiltration rate, ventilation and shading coefficient, of which the sum relative sensitivity is about 91.06%. The results are evaluated in terms of energy and economic analysis. On the other hand, it appears that the cost-effective method improves the efficiency of investment management in building energy. [ABSTRACT FROM AUTHOR]

Effective and reversible iodine adsorption is among the most important means to solve nuclear pollution. Herein, a novel electron-rich hypercrosslinked polymer (HCP) was obtained via a simple photocycloaddition of the cinnamoyl-containing polyimide precursor. The resulting polymer showed a high specific surface area of 531 m2 g−1 and high thermal stability. Taking advantage of the high porosity, high electron-rich heteroatoms contents and π-electron conjugated backbone, the material exhibits excellent iodine capture performance, including ultrahigh iodine vapor capture (528 wt%) and iodine removal efficiency from aqueous solution. The capture behavior is consistent with the pseudo-second-order model and the spectral results indicate that the captured iodine existed in the form of polyiodide anions. Furthermore, the HCP maintained 90.76% of the uptake capacity after four cycles. This study provides a new proposal for the preparation of functional HCP as an efficient iodine absorbent to solve environmental issues. [Display omitted] • Novel electron-rich hypercrosslinked polymer (HCP) was obtained via a simple photocycloaddition of polyimide precursor. • The resulting polymer showed a high specific surface area of 531 m2 g−1 and high thermal stability. • It exhibits excellent iodine capture performance (528 wt%) and iodine removal efficiency in aqueous solution (83.5%). • The HCP maintained 90.76% of the uptake capacity after four cycles. [ABSTRACT FROM AUTHOR]

In this paper, the off-design performance of an ejector-expansion refrigeration cycle (EERC) using several hydrocarbon refrigerants including propane, butane, isobutane and propylene as working fluids is analyzed based on energy and exergy concepts. A constant-pressure ejector flow model is employed in the simulation. The results indicate that, the hydrocarbon-based EERCs have higher COP, volumetric cooling capacity and exergy efficiency, as well as lower exergy destruction compared with the standard refrigeration cycle. In addition, as the difference between the condensing and evaporation temperatures increases, the advantages of the hydrocarbon-based EERCs become more prominent under off-design conditions. Propane and propylene used in the EERC in general have better performance than those of isobutene and butane. [ABSTRACT FROM AUTHOR]

Abstract: An electrochemical method was developed to measure the enzymatic activity of alcohol dehydrogenase (ADH) by monitoring the amount of reduced nicotinamide adenine dinucleotide (NADH) generated in the catalysed oxidation of ethanol by ADH. The concentration of NADH was determined by amperometric measurements, which recorded the oxidation current of NADH versus time on reduced graphene oxide and functionalised multi-walled carbon nanotube modified electrodes. The initial reaction rates and the apparent Michaelis constants of the enzymatic reaction were obtained in the absence and presence of Al3+ and nanometre-sized tridecameric aluminium polycationic (nano-Al13) species. The results showed that Al3+ and nano-Al13 exhibited inhibitory effect on the enzymatic activity of ADH. Fluorescence and circular dichroism spectra indicated the inhibitory effect was likely caused by the conformational changes of ADH and/or NADH induced by Al3+ and nano-Al13. [Copyright &y& Elsevier]

Abstract: The complexation of reduced glutathione (GSH) in its free and Al(III)-bound species in acidic aqueous solutions was characterized by means of multi-analytical techniques: pH-potentiometry, multinuclear (1H, 13C and 27Al) and two-dimensional nuclear Overhauser enhancement NMR spectroscopy (1H, 1H-NOESY), electrospray mass spectroscopy (ESI-MS), and ab initio electronic structure calculations. The following results were found. In the 25°C 0.1M KCl and 37°C 0.15M NaCl ionic medium systems, Al3+ coordinates with the important biomolecule GSH through carboxylate groups to form various mononuclear 1:1 (AlHL, AlH2L and AlH−1L), 1:2 (AlL2) complexes, and dinuclear (Al2H5L2) species, where H4L+ denotes totally protonated GSH. Besides the monodentate complexes through carboxylate groups, the amino groups and the peptide bond imino and carbonyl groups may also be involved in binding with Al3+ in the bidentate and tridentate complexes. The present data reinforce that the glycine carboxylate group of GSH has a higher microscopic complex formation constant than γ-glutamyl carboxylate. Compared with simple amino acids, the tripeptide GSH displays a greater affinity for the Al3+ ion and thus may interfere with aluminum’s biological role more significantly. [Copyright &y& Elsevier]

Abstract: The γ-LiAlO2:Cr3+ ceramics were successfully fabricated using multi-mode cavity microwave furnace, and the sample''s infrared absorption spectrum was measured at room temperature. There are six bands in the range 1700–2900cm−1. Using the crystal-field theory and introducing the average covalent factor model, we calculated the d–d transitions of Cr3+ ions in γ-LiAlO2 and firstly explained these bands in the infrared region. These calculation results are in good agreement with the optical experiment data. [Copyright &y& Elsevier]

• Extractants were screened from three different perspectives. • Ethyl tert -butyl ether purification process based on multi-objective optimization. • Use heat integration to enhance processes. • Recovery of extractant by pervaporation technology. • Evaluate the processes from the economy, environment, energy and exergy. Ethyl tert -butyl ether, an environmentally friendly gasoline additive, has high industrial application value, which is very necessary to study the refined process. The development of an efficient ternary azeotropic separation and purification process promotes the establishment of an environment-friendly society. In this study, two common methods of extractive distillation and extractive pressure swing distillation and three enhanced methods of heat integration process and coupled pervaporation technology were used to efficiently separate ethyl tert -butyl ether/ethanol/water. The most effective and environmentally friendly extractants were screened by analyzing the effects of relative volatility, intermolecular interactions and biotoxicity. The multi-objective optimization method was adopted to optimize the process with the annual total cost and gas emissions as the goals and the optimal parameters and process plans for extractive distillation and extractive pressure swing distillation were obtained. Finally, five technological processes are analyzed from the aspects of economy, environment, energy and exergy. It was found that the use of pressure swing distillation would greatly increase the economic and energy loss. And compared with the conventional process, the total annual cost of the extractive distillation coupled pervaporation process was reduced by 15.12 % and the environment was reduced by 20.17%. The coupling process that is of great significance to the purification of ethyl tert -butyl ether, an environmentally friendly gasoline additive was superior to the single distillation process in terms of economy, environment and energy. [ABSTRACT FROM AUTHOR]

• The antiscaling simulation, equipment design and experiment is studied. • A mathematical model is built to describe the fluid flow in the vertical well. • Flashing point can be calculated based on wellhead and well bottom parameters. • Chemical inhibitor can solve calcium carbonate precipitation problem. Calcium carbonate precipitation is a common problem in geothermal industry, which dramatically hampers geothermal development and also increases maintenance costs. To solve such a problem, here the whole process of scaling and antiscaling, including scaling type analysis, scaling process simulation, flashing point determination, antiscaling equipment design, inhibitor selection, antiscaling experiment and inhibition efficiency evaluation is investigated. The results show that the flashing point can be calculated by a mathematical model using wellhead and well bottom parameters. Chemical inhibitors injected into brine below the flashing point can effectively solve the problem of calcium carbonate precipitation, obtaining an inhibition efficiency of 89.37% with an inhibitor concentration of 25.61 ppm. [ABSTRACT FROM AUTHOR]

In this work, through the study of the obtained Cu–Ti–Si–N intermediate products by controlling the reaction degree of Ti and Si 3 N 4 powder in Cu melts at 1250∼1300 °C, the effects of different Ti: Si 3 N 4 mass ratios on the microstructure evolution of Ti–Si 3 N 4 reaction in Cu melts were verified. When the mass ratio of Ti: Si 3 N 4 is higher, such as 3.09:1, TiN will cooperate with Ti 5 Si 3 and depend on each other to nucleate and grow to form TiN/Ti 5 Si 3 composites. The formed TiN are spherical and wetted by Ti 5 Si 3 to uniformly disperse in Cu melts. As a result, the TiN–Ti 5 Si 3 hybrid reinforced Cu matrix composites will be formed. However, when the mass ratio of Ti: Si 3 N 4 is lower, such as 1.37:1, Ti and Si 3 N 4 will firstly react to form TiN and Ti–Si liquid. The formed TiN are irregularly polygonal and connect with each other. The Ti–Si liquid will combine with Cu melts to form Cu–Ti–Si liquid and finally form δCu 4 Si, ηCu 3 Si and τ 1 -CuSiTi phases during the colling stage. In this case, TiN are difficult to be wetted, and the Ti–Si 3 N 4 compact will keep its original shape and not spread in Cu melts. The microstructure evolution of Ti–Si 3 N 4 compacts in Cu melts under different Ti: Si 3 N 4 mass ratio. [Display omitted] [ABSTRACT FROM AUTHOR]

Papillary craniopharyngioma (PCP) was previously believed to occur only in adults. Sporadic pediatric PCP (PPCP) confirmed by detection of BRAF V600E mutation has been reported since 2018, but is often misdiagnosed before being diagnosed definitively. We aimed to evaluate PPCP characteristics and propose diagnostic criteria for prompt diagnosis, seeking to reduce patient morbidity and mortality and reduce costs linked to misdiagnosis. This study included 5 patients with PPCPs whose data were retrieved retrospectively from among 1032 patients with craniopharyngiomas admitted to Sanbo Brain Hospital Management Group from March 2017 to May 2021. Patients' demographics, clinical presentation, tumor imaging characteristics, histopathologic results, surgical approaches, and postoperative outcomes were analyzed. PPCP was misdiagnosed intraoperatively as sellar abscess (n = 4) or Rathke cleft cyst (n = 1). Preoperative magnetic resonance imaging showed that all tumors were under the saddle diaphragm, and the cyst wall was enhanced (n = 5). Computed tomography scans showed scattered high-density signs (n = 4). No recurrence was noted after complete resection. Postoperative hypothalamic dysfunction was mild. BRAF V600E mutation was confirmed in all cases by sequencing and immunohistochemistry. Immunohistochemistry showed granulation and inflammation and MPO, CD3, CD20, CD38, CD68, and CD163 were positively expressed. Misdiagnosis of PPCP is responsible for failed surgical treatment. We propose that prompt diagnosis of PPCP can be achieved if preoperative magnetic resonance images show the tumor under saddle diaphragm with tumor wall enhancement and computed tomography scans show high-density signs scattered in the tumor, which leads to safe, effective tumor resection. Our proposed diagnosis and treatment strategy for PPCP reduces morbidity and mortality. [ABSTRACT FROM AUTHOR]

In this study, the formation processes of TiC in a Cu–Ti–SiC system following the addition of a Ti–SiC mixture into a Cu melt were studied by analyzing the reaction intermediates, and the influence of the synthesis processes on the TiC microstructure was examined. It is found that, upon the addition of Ti–SiC into the Cu melt, the reaction of Ti and Cu to form a Cu–Ti liquid phase occurred first, followed by the reaction between liquid Ti, denoted as Ti(l), and SiC. However, the Ti(l)–SiC reaction processes vary depending on the reaction conditions and significantly influence the microstructures of the TiC particles, especially their dispersion in the Cu matrix. Under certain conditions, such as a lower reaction temperature and larger SiC size, SiC does not directly react with Ti(l). It first transforms into graphite through the outward diffusion of Si; subsequently, the graphite phase reacts with Ti(l) to form TiC. In this case, the synthesized TiC particles tend to connect with each other to form agglomerates. Under conditions conducive to the direct reaction of the Ti(l)–SiC system, such as a higher reaction temperature and smaller SiC size, Ti(l) and SiC first react to form a Ti 3 SiC 2 phase that then decomposes into TiC x and Ti–Si phases and eventually transforms into TiC y (x > y) and amorphous or crystalline Si. In this case, the formed Ti–Si or Si phase can prevent the agglomeration of TiC particles, leading to their more uniform distribution in the prepared Cu matrix composite. [ABSTRACT FROM AUTHOR]

Abstract: Solar radiation measurements are not easily available, especially for the diffuse solar radiation. In this study, two models for estimating the diffuse solar radiation are proposed based on multiple predictors including the clearness index, relative sunshine duration, ambient temperature and relative humidity. One of them aims to increase the estimation accuracy, and the other aims to estimate the diffuse solar radiation direct from other meteorological elements in the absence of the global solar radiation. For a case study, the performance of the proposed models is validated by comparing with eight existing models selected from literature against the measured data at Guangzhou station in China. Through the analysis based on statistical error tests, results show that the two models can estimate the monthly average daily diffuse solar radiation with good accuracy. [Copyright &y& Elsevier]

Abstract: There are many solar constant values given and adopted by researchers, leading to confusion in estimating solar radiation. In this study, some solar constant values collected from literature for estimating solar radiation with the Ångström–Prescott correlation are tested in China using the measured data between 1971 and 2000. According to the ranking method based on the t-statistic, a strategy to select the best solar constant value for estimating the monthly average daily global solar radiation with the Ångström–Prescott correlation is proposed. [Copyright &y& Elsevier]

The amount of food waste generated annually has increased due to rapid urbanization. Food waste that is not effectively treated not only pollutes the environment but also endangers human health indirectly. To realize the resource treatment of food waste, a novel combined cooling, heating, power, and dehumidification system based on food waste plasma gasification (PG) is proposed. First, the PG and solid oxide fuel cell (SOFC) models are validated, and then energy analysis and exergy analysis of the hybrid system are conducted. Finally, the influence of crucial parameters on energy output and efficiency is analyzed. It was found that the net electrical, thermal, and exergy efficiencies of the hybrid system were 54.60%, 84.22%, and 51.15%, respectively, under the designed conditions. The moisture removal rate, humidity efficiency, and CO 2 removal rate of the hybrid system were 20.16 g/kg, 93.66%, and 97.17%, respectively. The largest part of the exergy destruction was that of the plasma gasifier that accounted for approximately 35.45% of the total exergy destruction related to the plasma torch's high power consumption. This system could efficiently and cleanly convert food waste into energy and could provide a new method for the efficient utilization of food waste. [ABSTRACT FROM AUTHOR]