Search

Osteoporotic vertebral compression fractures (OVCFs) can be treated with percutaneous kyphoplasty (PKP). In contrast to conventional PKP, the novel deflectable percutaneous kyphoplasty (DPKP), is a unilateral transpedicular approach procedure allowing a similar bilateral puncture effect, which owes to the deflectable curved bone expander creating a transcentral line cavity to achieve uniform distribution of cement and biomechanical balance while reducing operative time and radiation exposure.The purpose of this study was to prospectively compare and evaluate an innovative surgical procedure, DPKP, versus conventional bilateral percutaneous kyphoplasty (BPKP).This is a prospective randomized controlled trial (RCT).The totality of the participants (n=90) suffering from OVCFs between May 2019 and October 2020, were randomized by SAS 9.3 to generate a block randomization sequence, which was utilized to randomize the groups in a 1:1 ratio, assigned to the DPKP group (n=45) and the BPKP group (n=45) to undergo accordingly procedures.The primary outcome was the total operative time. The secondary outcomes included: comparative assessment of visual analog scale (VAS) scores, Oswestry disability index (ODI), kyphosis angle (KA), anterior border height (AH) of the injured vertebra, frequency of intraoperative X-ray fluoroscopy, the injection volume, distribution pattern and leakage rate of bone cement.All subjects underwent assessment by at least one senior orthopedist and radiologist for the VAS scores, ODI, KA, AH of the injured vertebra, total operative time, the injection volume, distribution pattern, leakage rate of bone cement at preoperative and 24 hours, 6 months, and 1 year postoperatively. Inclusion criteria for subjects in this prospective study were as follows: (1) 60age80 years old; (2) preoperative spinal X-ray, CT, and MRI confirmed as single-segment, fresh thoracolumbar OVCFs (T5-L5, 15%collapse80%); MRI shows low signal on T1-WI and high signal on T2-WI, especially with STIR high signal characterized by vertebral edema; (3) painful OVCFs refractory to medical treatment, 2 weeksSymptom duration3 months;(4) With significant physical signs of local tenderness; (5) T score of bone mineral density (BMD)-2.5.The total operative time was significantly reduced in the DPKP group (43.3±19.58 minutes, 95% CI: 37.23-49.37) compared to the BPKP group (55.16±11.56 minutes, 95% CI: 51.78-58.54) (p.001). Compared to the BPKP group (frequency of intraoperative X-ray fluoroscopy: 43.42±8.64, 95% CI: 40.90-45.95; the volume of bone cement injected: 5.56±0.85 mL, 95% CI: 5.31-5.81), the frequency of intraoperative X-ray fluoroscopy (30.05±17.41, 95% CI: 24.66-35.45) and volume of bone cement injected (5.08±0.97 mL, 95% CI: 4.78-5.38) significantly reduced in the DPKP group compared to the (p.001). In addition, compared to the preoperative period, both groups showed significant improvements in the postoperative VAS scores, ODI, KA, and AH (p.001), but there was no statistical difference between the DPKP and BPKP groups (p.05) at any time-point. Interestingly, although without statistical differences, a tendency towards a lower rate of bone cement leakage was observed in the DPKP group.Our study results indicate that the innovative DPKP is as safe and effective as BPKP in relieving pain, improving the patient's quality of life, and reconstructing vertebral body height. Particularly, DPKP did reduce operative time and radiation exposure compared to BPKP, which correlated with unilateral and bilateral exposure procedures. Moreover, the final cement distribution was less predictable in DPKP, and further studies are warranted to clarify the advantages of DPKP versus conventional unilateral percutaneous kyphoplasty (UPKP) and BPKP.

By leveraging self-supervised tasks, pre-trained language model (PLM) has made significant progress in the field of machine reading comprehension (MRC) . However, in classical Chinese MRC (CCMRC) , the passage is typically in classical style, but the question and options are given in modern style. Existing pre-trained methods seldom model the relationship between classical and modern styles, resulting in overall misunderstanding of the passage. In this paper, we propose a contrastive learning method between classical and modern Chinese in order to reach a deep understanding of the two different styles. In particular, a novel pre-training task and an enhanced co-matching network have been defined: (1) The synonym discrimination (SD) task is used to identify whether modern meaning corresponds to classical Chinese. (2) The enhanced dual co-matching (EDCM) network is employed for a more interactive understanding of the classical passage and the modern options. The experimental results show that our proposed method improves language understanding ability and outperforms existing PLMs on the Haihua, CCLUE, and ChID datasets.

The aim of this study was to investigate the phase transformation and kinetics of the solid-state reaction of CaO-V2O5, which is the predominant binary mixture involved in the vanadium recovery process. Thermal analysis, X-ray diffraction spectroscopy, scanning electron microscopy, and energy dispersive spectrometry were used to characterize the solid-state reaction of the samples. The extent of the solid reaction was derived using the preliminary quantitative phase analysis of the X-ray patterns. The results indicate that the solid reaction of the CaO-V2O5 mixture is strongly influenced by the reaction temperature and CaO/V2O5 mole ratio. The transformation of calcium vanadate involves a step-by-step reaction of CaO-V2O5, CaO-CaV2O6, and CaO-Ca2V2O7 depending on the CaO/V2O5 mole ratio. The kinetic data of the solid reaction of the CaO-V2O5 (1:1) mixture followed a second-order reaction model. The activation energy (Ea) and preexponential factor (A) were determined to be 145.38 kJ/mol, and 3.67 × 108 min−1, respectively.

The solid-state reaction and diffusion behaviors of CaFe2O4 and TiO2 were investigated using a diffusion couple method at 1373 K to 1473 K under air atmosphere, and an in situ XRD method was used to analyze the solid-state reaction process. The reactions between calcium ferrite and TiO2 in the solid state are displacement reactions that produce perovskite and Fe2O3. The diffusion interface was divided into three layers based on phase analysis: layer I was composed of CaTiO3; layer II was composed of Fe2O3, CaTiO3, CaFe2O4, and Ca2Fe2O5; and layer III was composed of CaTiO3, Fe2O3, CaFe2O3, and CaFe4O7. The interface was formed in three stages. In stage I, CaTiO3 formed at the interface. In stage II, the gradual thickening of layers I and II was accompanied by the growth of the amount of CaTiO3 phase. In stage III, CF decomposed into CF2, and layer III formed. Micropores were formed in layer II due to the Kirkendall effect, and the diffusion rate of Ca2+ in CaFe2O4 was greater than that in CaTiO3. The squared thickness of layer I was found to depend linearly on time, and the expression for predicting the thickness of layer I was proposed: $$ \Delta x = ( 1. 1 7 3 1\times 10^{ - 18} T^{2} - 3.0206 \times 10^{ - 15} T + 1.9652 \times 10^{ - 12} )^{{\frac{1}{2}}} \cdot t^{{\frac{1}{2}}} $$

The present study monitored the foaming phenomenon originating from the reaction of titanium-bearing blast furnace slag by using the relationship between the current change in a circuit and the foaming height. A series of experiments at room temperature and high temperature were designed to check the feasibility and reproducibility of the experimental apparatus. Experiments at different levels of basicity and TiO2 content at high temperature were designed to determine the effect of these parameters on the relationship between the foaming height and current. It was proved that the electric current method used in this study to monitor the real-time foaming process is feasible and reliable. The relationship between the foaming height and current change was also established.

This study examines the influence of household real estate on self-employment probability using a probit model based on four-phase Chinese General Social Survey microsurvey data. Our baseline results show that household real estate substantially increases the probability of personal self-employment. To solve endogeneity, we consider the Chinese marriage tradition in which parents who have male offspring prepare more real estate for their children. Using child gender ratio as an instrumental variable of household real estate, we find that real estate has a significant positive effect on self-employment. Moreover, real estate enhances a family’s risk-sharing ability, thus increasing the probability of individual self-employment. Household real estate helps enhance an individual’s social capital, thereby promoting self-employment. However, household real estate also promotes other personal investment, such as stocks, funds, and other assets, forming a crowd-out effect on self-employment.

V2O3 was prepared by reducing V2O5 powder using H2 as the oxygen carrier. To initially determine reasonable experimental for the H2-based reduction, oxygen potential and equilibrium calculations were performed. The reaction sequence of the V2O5 powder reduction was predicted by V O phase diagram assessments and was then verified by XRD and XPS measurements under various experimental condition. It was observed that the reduction followed the path of V2O5-VnO2n+1(n = 3 and 6)-VO2-VnO2n-1(n = 7, 6, 5, 4, and 3)-V2O3. Isothermal reduction experiments and kinetic analysis were performed using thermogravimetric analysis (TGA) at 813 K, 823 K, and 833 K, under a pure H2 gas flow. The entire reduction process, from V2O5 to V2O3, obeyed the unreacted shrinking core model (with random instant nucleation and three-dimensional growth of nuclei) and was controlled by chemical reactions. Mathematical fitting showed that the reduction process could be described as G(α) = [−ln(1-α)]1/3, and the apparent activation energy was determined to be 47.11 kJ·mol−1.

Purpose: To determine the effect of Deltex E3 Ubiquitin Ligase 3L (DTX3L) on the radioresistance of prostate cancer (PCa).Methods: A PCa cell model of radioresistance was established via exposure of cancer cell lines to fractionated radiation. The MTT {(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)} assay and western blotting were performed to evaluate the impact of DTX3L on cell survival and DNA damage repair. The molecular mechanism of action was evaluated by western blotting.Results: DTX3L was elevated in PCa cell lines compared with normal primary prostate epithelial cells (p < 0.01). The survival of PCa cells exposed to radiation was promoted by overexpression of DTX3L, while knockdown of DTX3L abrogated the radioresistance. Moreover, overexpression of DTX3Ldecreased phosphorylation of histone H2AX (γH2AX) and increased Rad51 levels (p < 0.01). However, knockdown of DTX3L reversed the accumulation of γH2AX and Rad51. Phosphorylation of AKT was promoted by DTX3L overexpression, but was reduced by DTX3L knockdown (p < 0.01). Inhibition of AKT (protein kinase B) counteracted the promotion ability of DTX3L on the radioresistance of PCa cells via decreased cell survival ratio, and also inhibited DNA damage repair via accumulation of γ-H2AX and depletion of Rad51 (p < 0.01).Conclusion: DTX3L increases the resistance of prostate cancer to radiotherapy and DNA damage repair in PCa via AKT pathway, indicating a potential therapeutic strategy to overcome radioresistance in PCa. Keywords: DTX3L (Deltex E3 Ubiquitin Ligase 3L), DNA damage, Phosphorylation, Radioresistance, AKT, Protein kinase B, Prostate cancer

A novel process of composite roasting with CaO/MgO and subsequent acid leaching was proposed to improve the recovery rate of vanadium from Linz–Donawiz (LD) converter vanadium slag. The effects of the MgO/(CaO+MgO) molar ratio and the roasting and leaching parameters on the recovery of vanadium were studied. The results showed that the leaching efficiency of vanadium decreased from 88% to 81% when CaO was replaced completely by MgO; however, it could be improved by roasting with the composite of CaO/MgO. The maximum vanadium leaching efficiency of 94% was achieved under the optimum MgO/(CaO+MgO) mole ratio of 0.5:1. The results from X-ray diffractometry (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM−EDS) confirm that the formation rate of acid-soluble vanadates can be enhanced during roasting with the composite of CaO/MgO and that the leaching kinetics can be accelerated owing to the suppression of calcium sulfate precipitation.

The carbothermic reduction of an ilmenite concentrate, followed by wet magnetic separation, was performed with varying additions of Na2CO3 to generate metallic iron and a titanium-rich slag. The si...

Prostate cancer is one of the leading causes of death in men all over the world. Treatment options such as androgen ablation therapy and cytotoxic agents have many undesirable side effects, narrow therapeutic windows, or other limitations. In this research, we have explored the effects of paeonol on prostate cancer and its mechanism of action. Our results have shown that paeonol reduced the viability of prostate cancer cells in a dose-dependent manner. The wound-healing assay, a surrogate marker of tumor metastasis, showed that the relative wound width of 10 µM group was less than that of 50 µM paeonol-treated cells. Besides, the results of the transwell assay also showed that the number of migrated cells was significantly lower after treatment with 50 µM paeonol compared to the 10 µM group. The Western blot results showed that paeonol treatment induced a decrease in the mesenchymal markers (vimentin and N-cadherin), while the epithelial marker (E-cadherin) increased in a dose-dependent manner suggesting that paeonol effectively inhibits the epithelial-mesenchymal transformation in PC3 cells. Furthermore, the expression of STAT3 and p-STAT3 was also decreased after paeonol treatment, which indicated that the STAT3 signaling pathway was inhibited by paeonol. To conclude, the results summarized in this paper suggest that paeonol could be a potential candidate in the treatment of prostate cancer.

BACKGROUND: The dissolution behavior of calcium vanadates is vital for the vanadium extraction process, as well as the utilization of calcium vanadates based function materials. Therefore, the dissolution kinetics study of calcium vanadates (CaV₂O₆, Ca₂V₂O₇, and Ca₃V₂O₈) in sulfuric acid are presented. The effects of stirring speed, solid/liquid ratio, pH, and temperature on the dissolution rate of calcium vanadates were determined. The mineralogical and microstructure of the residue after dissolution are also performed. RESULTS: The results showed that the dissolution rate of calcium vanadates significantly increased with the increase of temperature from 30 to 70 °C. Under the conditions with solid/liquid ratio of 1:150 g mL⁻¹, temperature range of 30 to 70 °C, and pH of 4, the rate of Ca₃V₂O₈ dissolution is the fastest, followed by Ca₂V₂O₇ and CaV₂O₆, especially at low temperature. CONCLUSION: The mineralogical analyses results showed that the main products for the dissolution of Ca₂V₂O₇ and Ca₃V₂O₈ are needle‐like CaSO₄·0.5H₂O, whereas for CaV₂O₆ are undissolved CaV₂O₆ and hydrolyzed V₂O₅. The dissolution kinetics indicate that the dissolution of CaV₂O₆ follows second‐order pseudo‐homogeneous model, whilst Ca₂V₂O₇ and Ca₃V₂O₈ follow the diffusion through the product or ash layer model. The apparent activation energies for the dissolution of CaV₂O₆, Ca₂V₂O₇, and Ca₃V₂O₈ were determined as 46.44, 38.72, and 23.50 kJ mol⁻¹, respectively. © 2020 Society of Chemical Industry

The foaming behaviour originating from the reduction of iron oxide in molten CaO–SiO2–MgO–Al2O3–TiO2 slag was studied at 1500°C with the aid of a real-time foaming process monitoring system...

Autism spectrum disorder (ASD) is a serious disorder that begins early in life and continues throughout life. Children diagnosed early with ASD are more responsive to therapeutic interventions and have less impairment of social and language functions whereas current diagnostic measures are mostly applied to children older than one year and lack the appropriate biological markers for early diagnosis of ASD. In this study, we used datasets GSE6575 from GEO to comprehensively analyze the mRNA expression profile of ASD, including 35 ASD samples and 12 normal control samples. Firstly, we looked for 50 different genes, and then we did a enrichment analysis of those genes. The results of enrichment analysis showed that these differential genes were mainly concentrated in the response to viruses, immune regulation of inflammation and energy metabolism Secondly, String database was used to construct Protein–protein interaction (PPI) network of differential genes. Finally, cytoscape plug-ins Cytohubba was further used to search for Hub genes and the diagnostic value of these Hub genes was verified by subject operating characteristic curves. among which two genes IL2RB and PRF1 had good sensitivity and specificity for the early diagnosis of autism. the areas under ROC curve were 0.855,0.830 for IL2RB, PRF1.Data analysis using GEO database can provide some new insights into the etiology of ASD and provide some possible biomarkers and therapeutic targets for early diagnosis and treatment of ASD.

The high-temperature heat capacity of sodium metavanadate (NaVO3) was measured using a differential scanning calorimeter (DSC) for temperature in the 303–573 K range, and using a multi-high temperature calorimeter 96 line for temperature in the 323–773 K range. The obtained high-temperature heat capacity of NaVO3, as a function of temperature, was modeled as: Cp = 22.08251 + 0.3449T-3.32185 × 10−4T2+9.76468 × 10−8T3 (298.15-773 K). The temperature dependence of the heat capacity was then used for computing changes in the enthalpy, entropy, and Gibbs free energy. The non-isothermal kinetics of the solid-solid phase transformation of NaVO3 were examined by using various DSC curves. The findings indicate that the reaction mechanism of the solid-solid phase transformation of NaVO3 includes two stages, the first of which is controlled by a fibril-like mechanism, while the second is controlled by a disc-type mechanism. In the present study, the apparent activation energy of the solid-solid phase transformation of NaVO3, which was calculated using the Kissinger method and the Ozawa method, was equal to 628 ± 14 kJ·mol−1 and 610 ± 12 kJ·mol−1, respectively.

This study investigates the impact of institutional quality (IQ) on the financial development (FD) of 15 emerging and growth-leading economies (EAGLEs). We show that an institutional framework can ...

This study investigates the effect of politically connected independent directors on a firm's likelihood of committing fraud in China. We classify the political backgrounds of independent directors into three categories based on their employment histories: local background, central background, and local and central background. Using corporate fraud data from 2000 to 2014, we find that independent directors with local political backgrounds significantly reduce the likelihood of a firm committing fraud. Further analysis shows that locally connected independent directors are more likely to have both employment experience in regulatory agencies and financial/accounting/law expertise.

In this study, hydrogen reduction of raw and preoxidized ilmenite concentrates powder, with particle size less than 74 μm, is investigated using a thermal analyzer at 1123, 1173, and 1223 K in a 30% H2 + 70% Ar atmosphere. The reduction rate by hydrogen was found to be accelerated due to preoxidation treatment of the raw ilmenite concentrate. The reduction of both raw and preoxidized ilmenite concentrates can be divided into two stages: Fe3+→Fe2+ and Fe2+→Fe. The Fe3O4→FeO stage overlaps with the Fe2O3→Fe3O4 stage during reduction process of the preoxidized ilmenite concentrate. Moreover, the preoxidation treatment can effectively decrease the reduction activation energy. The scanning electron microscopy (SEM) and the X-ray powder diffraction (XRD) techniques were used to characterize the micromorphology and phase of the products. The promotion mechanism of reduction of ilmenite by hydrogen through preoxidation treatments is also discussed.

The effect of karrooite contents on the isothermal reduction kinetics of pseudobrookite-karrooite(Fe2TiO5-MgTi2O5) powder was investigated under a 30% CO/70% Ar atmosphere at 1123, 1173, and 1223 K. The reduction rate decreased with increasing karrooite contents and increased with increasing reduction temperatures. The reaction mechanism with different stages were studied. The average apparent activation energies were 38.34, 39.60, 41.92, and 89.56 kJ/mol for contents of 0%, 9.93%, 19.86%, and 39.72% karrooite, respectively. The mechanism of karrooite in blocking the reduction of pseudobrookite was clarified. The morphology of the reduced sample with different amounts of karrooite were also examined.

The electric arc furnace (EAF) smelting process, which produces titanium slag, is the most popular method for utilizing Panzhihua ilmenite concentrate. However, the EAF process involves high energy consumption, high pollution, and low efficiency due to the high smelting temperature, the large amount of dust produced, and the long smelting period. An economical and clean method for semi-molten reduction followed by magnetic separation to produce titanium slag from Panzhihua ilmenite concentrate was presented. In this paper, the semi-molten reduction process was studied and the effect of reduction temperature, C/O molar ratio, and the addition dosage of Na2SO4 on the metallization ratio, phase transformation, and size of metallic iron grain was discussed. The results showed that Na2SO4 and its subsidiary products can function as fluxing agent for decreasing the melting point of metal and slag, thus promoting the growth of metal particles, and achieving high efficiency and clean reduction of ilmenite concentrate. The action mechanism of Na2SO4 addition is also discussed.

Titanium carbides, oxides, nitrides and carbonitrides possess many special and excellent properties. But the high production cost caused by the traditional carbothermic reduction process severely limits the wide applications. In this study, a novel synthesis process has been proposed by reducing and carbonitriding TiO2 with CH4-H2-N2 gas mixture at low temperatures. The synthesis of Ti(C, N, O), reaction mechanism and the products composition have been investigated. Thermodynamic analysis indicated that TiO2 could be ultimately reduced and carbonitrided to Ti(C, N, O) by CH4-H2-N2 gas mixture. Based on the predictions of thermodynamics, the effects of reduction time, temperature, and gas composition have been studied experimentally. The obtained results indicated that increasing reduction temperature and introduction of N2 are beneficial to the synthesis of Ti(C, N, O). Finally, the optimum reaction conditions have been obtained. The density functional theory (DFT) results further demonstrated the reaction mechanism. This work provides a new approach to prepare metallic carbonitrides from their oxides.

Magnesium-vanadium oxides have attracted significant attention owing to their promising optical and catalytic properties. Here, experimental and first-principles calculations based on density functional theory (DFT) were combined to examine the electronic, optical, lattice dynamical, and thermodynamic properties of the magnesium pyrovanadate (Mg2V2O7) and magnesium orthovanadate (Mg3V2O8). We first prepare high-purity polycrystalline Mg2V2O7 and Mg3V2O8 crystals using the solid-state reaction method. The good agreement between experimental and theoretical results indicate that these two compounds are ideal candidates for photocatalysts or optoelectronic devices. The lattice dynamics are revealed by Raman spectroscopy and phonon dispersion curves. The thermodynamic properties over a wide range of temperatures were also obtained. This study not only promotes the functional applications of Mg2V2O7 and Mg3V2O8 compounds but also highlights a guidance for understanding the thermodynamic phase diagram of magnesium-vanadium oxides.

In order to obtain a lower detection limit in electrochemical detection, the choice of signal amplification strategy is of great importance. In this work, we describe an electrochemical sandwich aptasensor based on a signal amplification system involving two thrombin (TB) aptamers (TBA1 and TBA2), gold nanoparticles (AuNPs) as aptamer carriers, and [Ru(NH3)6]3+ for signal conversion. In the presence of the target thrombin, TBA1 and TBA2 specifically bind to TB, and the TBA1-TB-TBA2 complexes cause the formation of a sandwich structure, meaning more [Ru(NH3)6]3+ can be adsorbed on the negatively charged phosphate backbone of the aptamers, resulting in an increase in the differential pulse voltammetry (DPV) current. Under optimal conditions, the aptasensor exhibited a linear range of 1 fM to 6 pM and a limit of detection of 0.1429 fM (S/N = 3) for TB. The proposed aptasensor displayed an excellent selectivity and reproducibility. Importantly, the aptasensor was capable of detecting TB in serum samples successfully.

In this study, a novel process is proposed to produce titanium slag from Panzhihua ilmenite concentrate. The carbothermic reduction of ilmenite concentrate, followed by wet magnetic separation, was performed to generate metallic iron and a titanium-rich slag in the presence of sodium sulfate and sodium carbonate. This work investigated the influence of reaction time, sodium sulfate additive, and sodium carbonate additive on the metallization, the TiO2 grade in the non-magnetic fractions, and recovery of titanium dioxide. The results show that sodium carbonate increases the metallization, while sodium sulfate decreases the metallization of the reduced sample. In the presence of sodium carbonate, the highest metallization and recovery of titanium dioxide can reach up to 90.57% and 0.83, respectively. In addition, the mechanism of additives influence on the reduction process is also discussed.

As one of the critical intermediate compounds of the sodium roasting converter slag, sodium pyrovanadate (Na4V2O7) powder was synthesized by solid-state reaction using NaCO3 and V2O5 as raw materials in this study. The preparation was first evaluated by thermodynamic software FactSage® with the minimum Gibbs free energy principle. Effect of temperature (T) and partial pressure of carbon dioxide P(CO2) was analyzed, and the results indicated that the reaction proceeds extensively with increasing temperature and reducing P(CO2). TG-DSC was applied to further characterize the preparation process, and it can be found that the reaction proceeds extensively near 540 °C corresponding to carbon dioxide gas escaping. Non-isothermal kinetics with a single scan rate was applied to the solid-state reaction, the average apparent activation energy was obtained using Freeman–Carroll method, equal to 102 ± 6 kJ/mol by mathematic fitting. In addition, XRD further verified the phase composition of Na4V2O7, and a large number of voids were detected from SEM images caused by the gas release.

High-temperature heat capacity measurements can be a very powerful means to investigate and understand the properties of materials, and high-temperature heat capacity values are also the key thermodynamic data can be used for calculating phase diagram, chemical reaction, and multi-phase equilibrium. As one of the most promising method, drop calorimetry has attached much attention during the past years due to its special 3D thermal sensor, which provides more accurate measurement of high-temperature heat capacity. All the subsequent insightful analyses and further discussion should be based on correct experimental data. A few critical concerns about high-temperature heat capacity measurements by drop calorimetry were summarized in this study. Various possibilities in the measurements will be given to show how much the experimental data deviated from their exact values, and those concerns should be taken seriously during actual measurements in order to obtain reliable high-temperature heat capacity values. The sample properties such as water absorption capability, particle size, weight test, surface roughness are critical for Drop calorimetry. The stable room temperature is essential for measuring heat content of the sample. Various integration methods should be carefully considered and selected when face the different heat flow types before and after the Drop test.

The dissolution efficiency of vanadium is the key to improve the recovery of vanadium from vanadium-bearing converter slag by calcification roasting-acid leaching process. An improved process, which involves roasting with calcium–magnesium salts, followed by acid leaching, was found to have a positive effect on the vanadium recovery. In this process, CaO–MgO–V2O5 is the basic system in the roasting step. In this study, the dissolution behavior of calcium vanadates (CaV2O6, Ca2V2O7, and Ca3V2O8) and magnesium vanadates (MgV2O6, Mg2V2O7, and Mg3V2O8) in sulfuric acid was investigated. The effect of parameters, such as stirring speed, solid/liquid ratio, and pH value, on the dissolution behavior of vanadates were determined. The results shown that both of solid/liquid ratio and pH value have significantly effects on the dissolution efficiency of vanadium, while stirring speed has a relatively minor effect under the studied conditions. Furthermore, the dissolution efficiency of magnesium vanadates has been found much higher than that of calcium vanadates.

Vanadium extraction tailings are a kind of hazardous solid waste generated from the vanadium extraction process which using vanadium-bearing converter slag as raw materials. The comprehensive utilization of vanadium extraction tailings is becoming increasingly important due to the stricter environment regulations, cleaner production standards, and the shortage of valuable resources. Many advantages of comprehensive utilization of vanadium extraction tailings have been discovered, such as recover valuable metals, avoid waste of resources, increase economic benefits, reduce environmental pollution, and so on. Various comprehensive utilization of vanadium extraction tailings have been reviewed and compared, mainly focusing on the extraction of vanadium, iron, titanium, and gallium from vanadium extraction tailings and the preparation of titanium-iron black ceramic building materials, far-infrared coatings, converter slagging agents, and so on. The comprehensive condensation of pertinent facts is intended to provide a single reference source rather than the reader perusing many articles.

The reduction of chromium-bearing vanadium–titanium magnetite sinter (CVTMS) by CO was investigated at 1123–1223 K. The reduction degree increased with increasing temperature. The isothermal reduct...

The recycling of metallic iron is commonly the first step to fully use the converter slag, which is the biggest waste discharge in the steelmaking process. This study presents a proposed improved process of separating metallic iron from vanadium-bearing converter slag more efficiently. The mineralogical and morphological characteristics of the converter slag were first investigated, and the results showed that most of the iron was incorporated in the spinel and olivine. Grinding, sieving and magnetic separation were combined to recover metallic iron from the converter slag, and yielded approximately 41.5% of iron in which the iron content was as high as 85%, and the non-magnetic concentrate contains 8.56% vanadium with a yield of 95.3% and 8.63% titanium with a yield of 85.3%. The magnetic part can be used as the raw materials in the steel making process, whereas the non-magnetic part can be used as the raw materials for the further extraction of vanadium.

This study investigates the effect of political promotion incentives on the labor investment efficiency of firms by focusing on human capital misallocation. We show that 1) promotion incentives of local politicians significantly increase firm-level employment growth and decrease labor investment efficiency. 2) Causality is established using the number of death toll in local mining accidents to isolate exogenous shocks on the promotion incentives of local politicians, and placebo tests further confirm the causality. 3) For under-hiring firms, promotion incentives only increase the employment of low human capital, thus distorting human capital structure and decreasing labor investment efficiency. 4) Our findings are robust to alternative specifications. Overall, we highlight the political economy channel of human capital misallocation from the perspective of career concerns of local politicians.

A co-recovery process used to extract iron, chromium, and vanadium in the form of chromium–vanadium-bearing metallic iron from vanadium tailings via a semi-molten reduction-magnetic separation meth...