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To elucidate the formation mechanisms of burn-on sand and metal penetration during sand casting, some laboratory experiments were carried out at different temperatures (1813, 1833, 1853, and 1873 K) and holding time (20, 40, 60, and 90 min) to simulate the interaction between ZG13Cr9Mo1VNbN stainless steel and chromite sand. The results demonstrate that the defects primarily consist of a mixture of the liquid phase, chromite, and metal. The main components of the liquid phase are SiO2, MnO, MgO, Cr2O3, FeO, and Al2O3, and the formation of Cr2O3through interfacial redox reactions has been discovered. The presence of a liquid phase plays a pivotal role in influencing burn-on sand and metal penetration. Interface reactions are prioritized, with burn-on sand maintaining a predominant influence. As the liquid phase quantity within the sand escalates, there is a corresponding incremental rise in the incidence of metal penetration. Even a minimal presence of the silicon element in steel can impact the liquid phase’s formation. Moreover, the decomposition or dissolution of chromite sand is a significant factor in the development of burn-on sand and metal penetration. Thus, a thorough investigation into the conditions and contributing factors of this phenomenon is essential for its effective management and mitigation.

In the era of knowledge economy, enterprises are facing unprecedented competition and challenges. The process of globalization has accelerated the communication and integration between different cultures, making cross-cultural management an indispensable ability for enterprises. Especially in the field of human resource management, it is of great significance to build a competency model based on data mining technology to improve the cross-cultural communication ability, teamwork ability, and innovation ability of enterprise managers. The application of competency theory in the field of human resource management has the potential to completely revolutionize traditional management practices, enabling better adaptation to the continuous changes in the management environment. It plays a significant role in promoting the reform of the human resource management system. The aim of this paper is to build a competency model of human resource managers based on data mining technology and verify its effectiveness in cross-cultural background. It is assumed that the model can accurately evaluate the ability level of human resource managers and provide reference for enterprises to select and train outstanding talents. The experimental results demonstrate that the model achieves an accuracy of approximately 89%, a 93.3% improvement in efficiency, and a salary range exceeding 90%. The model is deemed reasonable, feasible, and highly precise in terms of competency assessment.

The interfacial oxygen transfer rate is one of the main factors to control the composition of alloys. The commonly employed method of studying the interfacial oxygen transfer rate is the chemical composition analysis; however, it is difficult to be studied in situ. Here, a new method of measuring the oxygen transfer rate at the gas–slag and slag–metal interfaces was reported based on electrochemical analyses. The interfacial oxygen transfer rate in the smelting process of Inconel 718 superalloy was investigated at 1723, 1773, 1823, and 1873 K. The experimental results show that the electrochemical method can measure the real-time oxygen content; hence, this method is promising in controlling the oxygen content in alloys. As the temperature increased, both the equilibrium oxygen content and the rate of oxygen absorption increased significantly, and the increase was the most obvious when the temperature was 1873 K. The possible reason is that the increase in temperature weakens the mass transfer resistance of the electric double layer at the interface, thus accelerating the oxygen transfer rate.

The loss of boron (B) in the rack plate steel during the electroslag remelting process has a significant impact on its mechanical properties. Therefore, it is necessary to design appropriate slags to suppress the loss of B. CaF2–CaO–Al2O3phase diagram was calculated to determine the basic slag. The influence of MgO and B2O3on the performance of the basic slag was studied to determine the optimal amount of MgO addition. The equilibrium reactions between rack plate steel and the 50.48 mass% CaF2–24.81 mass% CaO–24.71 mass% Al2O3–2 mass% MgO-ymass% B2O3(ywas 1–10) slag were studied to examine the variation in B content in the steel. Results indicate the presence of a temperature-qualified eutectic point in the CaF2–CaO–Al2O3phase diagram. With an increase in MgO content in the slag, the melting temperature of the basic slag initially decreases and then increases, while the electrical conductivity decreases. On the other hand, B2O3reduces the melting point of the slag and increases the equilibrium B content in the steel. The 50.48 mass% CaF2–24.81 mass% CaO–24.71 mass% Al2O3–2 mass% MgO-ymass% B2O3(ywas 5–7) slag can achieve the target range of B content in the steel, and its viscosity meets the requirements of electric slag remelting.

The clad teeming process can reduce the production cost of stainless steel clad plates. Nonetheless, many practical problems have not been resolved for industrialization. For the purpose, the ProCAST software is used to simulate the clad teeming process in the paper. An inverse algorithms is used to calculate the interface heat transfer coefficient based on the measured temperature curves. The temperature field and shrinkage cavity of clad ingot were simulated at different process parameters. A clad teeming experiment was carried out to prepare the clad ingots based on the simulated results. The interfacial morphologies, solidification structures and shear strength were examined. The temperature changes, shrinkage cavity, element diffusion and interfacial microstructures were analysized. The results show that the variation pattern of shrinkage cavities is in good agreement with the simulation results. The interface is well bonded with an excellent metallurgical bonding and the interfacial shear strength is up to 247 MPa in clad ingot under the experimental conditions. The diffusion of alloy elements leads to a chromized zone and a decarburized zone at the side of carbon steel and a carbonization zone at the side of stainless steel.

The Condensate and Feedwater System of the Chinshan BWR units is used to provide reliable and high-quality water to maintain the reactor water level during operation. If a Loss of Feedwater Heating (LFWH) event occurs, the core inlet subcooling increases and then induces corresponding power excursion and the reactor pressure rise. In the Chinshan Final Safety Analysis Report (FSAR), a loss of the feedwater temperature of 55.6°C (100°F) is conservatively assumed in the event. This study analyzes the integral reactor system response with RETRAN. Furthermore, a partial vessel model (PVM) of CFD is used to acquire the conditions of the fuel channel inlet to compensate the weakness of the RETRAN system model to generate detailed thermal-hydraulic conditions. The evaluation shows that the feedwater temperature drop is about 40°C which is lower than the FSAR value. In addition, the sensitivity study shows that the hot channel method underestimates the ?CPR about 0.025, and there is no direct relation between ?CPR and either of inlet subcooling or power fraction in transient, which is quite different from the conclusion of the hot channel method. Finally, the sensitivity study also proves the ?T of 55.6°C (100°F) used in FSAR analysis conservative enough to cover the worst channel with a margin of 0.015 in ?CPR.

Severe Pneumocystis pneumonia (PCP) has a poor prognosis, and its early and precise diagnosis is difficult in immunocompromised individuals. Therefore, this study explored the diagnostic value of metagenomic next-generation sequencing (mNGS) of peripheral blood in diagnosing severe PCP in patients with hematological diseases. This prospective study analyzed the clinical manifestations, mNGS results (from the peripheral blood), traditional pathogen detection results, laboratory test results, chest computed tomography (CT) images, treatments, and outcomes of severe PCP in hematological patients who were hospitalized in the 2 centers of the Affiliated Hospital of Soochow University between September 2019 and October 2021. A total of 31 cases of hematological diseases complicated with pulmonary infections, including 7 cases of severe PCP diagnosed by mNGS performed on peripheral blood samples, were analyzed. Traditional pathogen detection methods for PCP cannot be used. In contrast, the laboratory readings for Pneumocystis jirovecii (Pj) detected within 48 hours of symptom onset by mNGS on the 7 blood samples ranged from 12 to 5873, with a median value of 43. Under the guidance of the mNGS results, preemptive antimicrobial therapy with trimethoprim/sulfamethoxazole alone or in combination with caspofungin was administered to treat Pj. After treatment, 4 patients recovered, and 3 patients died of acute respiratory failure and acute respiratory distress syndrome (ARDS). MNGS performed on peripheral blood samples is optional but can provide early recognition of severe PCP and help guide empirical treatment in critical hematological patients.

In the process of light curing printing, layer steps are formed in the stacking direction. As these steps, i.e., by-products, affect the accuracy and quality of the printed surface significantly, avoiding their formation during printing is a prominent research topic.

To investigate the toxic effect of oscillating high glucose (OHG) versus persistent high glucose (PHG) in inducing oxidative stress and cellular apoptosis in human coronary artery endothelial cells (HCAECs) in vitro. HCAECs were incubated for 72 h continuously in normal glucose (5.5 mmol/L glucose), PHG (25 mmol/L glucose), OHG (5.5 mmol and 25 glucose mmol/L alternating every 6 h) and mannitol, respectively. Cellular viability, concentration of oxidative stress biomarkers (MDA and GSH) in the supernatants of cell culture, and intracellular ROS level were quantitated after exposure to different concentrations of glucose for a total 72 h. Apoptosis of HCAECs cultured with various glucose levels was evaluated by annexin V-FITC and PI staining followed by analysis with flow cytometry. The expressions of HO-1 and Nrf2 were measured by RT-qPCR and Western blotting at the end of the experiment. HCAECs cultured with PHG showed decreased cellular viability compared to those with normal level of glucose (p< 0.05). The decrease was more pronounced under OHG condition (p< 0.05). Cellular oxidative stress was provoked in HCAECs exposed to PHG with marked increased MDA level, reduced GSH concentration and elevated ROS production (p< 0.05). The stress was further amplified in the setting of OHG (p< 0.05). The cellular apoptosis was enhanced by culturing with PHG, and to a greater extent when incubated with OHG. Both expressions of HO-1 and Nrf2 were suppressed in HCAECs in persistent hyperglycemia condition, while the inhibition was more intense in the fluctuating hyperglycemia condition (p< 0.05). These findings indicate that OHG could be more detrimental to HCAECs than PHG. This is probably due to the enhancement of oxidative stress and cellular apoptosis induced by frequent glucose swings through the inhibition of Nrf2/HO-1 pathway.

The gasification performance of petroleum asphalt in a two-stage gasifier was investigated through experiments and simulations. The analysis results of asphalt samples show that the asphalt has characteristics of high volatile content, high calorific value, and low ash content. Coal pyrolysis model, gas-solid heterogeneous reaction model, gas homogeneous reaction model and Gibbs free energy minimization method were employed to build the two-stage entrained flow gasification model and simulate the asphalt gasification process using Aspen Plus software. The results indicate that the cold gas efficiency of asphalt is 3% higher than that of bituminous coal, while the consumption of coal and oxygen is 40% lower than that of bituminous coal. The gasification performance of asphalt is superior to that of coal. In addition, the cold gas efficiency of asphalt can be increased by about 3% when the two-stage gasification process is employed. The utilization rate of coal in the two-stage gasifier is much higher than that in traditional one-stage gasifier.

Superscalar processors contain complex control logic in order to extract sufficient instruction level parallelism (ILP). The issue logic is one of the main sources of power dissipation in current superscalar processors. It has been estimated that up to 30% of the energy consumed by a processor is in the issue logic. This paper presents a novel compiler assisted approach to power reduction where we use compiler analysis to pass information to the processor about the number of entries needed, allowing the processor to resize the issue queue dynamically which limit the number of instruction dispatched and resident in the queue reduces the energy consumption without adversely affecting performance. Compared with hardware scheme, our approach is simpler faster and saves more energy. Using the approach we achieve 43.3% dynamic and 28.5% static power savings.

To observe the clinical effect of combined acupuncture and kinesiotherapy on upper cross syndrome (UCS) by a parallel randomized clinical trial.

Nowadays, the earthquake occurs in a high frequency, and it not only imposes great financial loss on human’s property, but also leads many people to death. And the emergency self-rescued helmet, which is designed for earthquake, aims mainly at protecting the head of people who get stuck in the earthquake. It owns the dustproof mask and a water balloon which connects to the mask. The dustproof mask can be used to avoid suffocating caused by the rising dust, and the water balloon can provide the victims with the nutrients. The helmet carries the electronic equipment which can guide people to self-rescued process in earthquake, play the music to relieve the victims’ pressure and emit the distress signal, and it can raise the possibility of victims’ survival.

The relationship between carbon dioxide emissions and economic growth is analyzed and the results show that there exists a long-run equilibrium relationship between carbon dioxide emissions and economic growth to clear some people’s mind of doubts that energy conservation and carbon dioxide emissions reduction policy will hamper the economic development. When GDP increases, the carbon dioxide emission will increase too. Causality analysis shows that the unidirectional causal relationship exists and the direction is from GDP to carbon dioxide emission. The result implies that when a certain technique of carbon dioxide emissions reduction is used, it can not only reduce the carbon dioxide amount but promote the growth of GDP. Energy conservation and carbon dioxide reduction can form a new economic growth industry. To fulfill the promise of carbon dioxide emissions reduction to the world, China should make policies based on the relationship between carbon emissions and economic growth.

The microstructures have been investigated in steel plates with different rolling processes to find the reasons of yield ratio overseted standard in few high strength building steel plates produced in Echeng Iron and Steel Corporation. The effects of rolling path, rolling path depress ratio on microstructure and properties. Some reasons of yield ratio overseted standard have been analyzed. The results show that decreasing rolling paths and increasing depress ratio refined grains but unchanged area ratio and interlamellar spacing of pearlite. Yield strength excessively increased but tensile strength unchanged increased yield ratio. So, excellent properties can be obtained by applying the optimization process.

The effects of controlled rolling and controlled cooling parameters on the microstructure and mechanical properties of 550MPa grade engineering mechanism steel were investigated in the industrial trial conditions. The results show that the mechanical properties of 550MPa grade engineering mechanism steel are obviously improved by controlling finishing rolling temperature ranged from 780℃to 850℃, and by using accelerate cooling after rolling, ferrite grains are refined markedly of the steel which possess excellent strength and toughness behaviors.

A new class of chiral pyrrolidine–pyridinebased organocatalysts, available from commercially available starting materials, have been synthesized and shown to be very effective catalysts for the asymmetric Michael addition reactions of cyclicacyclicaromatic ketones and an aldehyde with nitro olefins, giving excellent yields up to 99 , diastereoselectivities synanti= 99:1, and enantioselectivities up to 99 . Based on the experimental results and ESIMS analysis of the intermediates, the mode of activity of the organocatalyst with the substrate was deduced. © WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

Abstract: Objective: To investigate the effects of ligustrazine (Li) on myocardial fibrosis in rats with pressure overload.Methods: Pressure overload rat models were established by constricting the abdominal aorta. Sixty-three SD rats were divided into 3 groups: Sham operated group (SOG, n = 21), operated group (OG,n = 21) and operated combined with ligustrazine group (OG+Li,n = 21). Each group was randomly assigned to seven time points: The 1st, 2nd, 4th, 7th, 14th, 21st and 30th day after operation. Three rats were included in each time point. Serial sections of cardiac tissues were examined and the morphological or morphometric analysis of the SOG, OG and OG+Li done by histopathological and computer image analyzer technique.Results: (1) It showed that there were reactive fibrosis (from the 4th day on after operation) and reparative fibrosis (from the 21st day on after operation) in the OG, while myocardial fibrosis in the OG+Li was alleviated. Though reactive fibrosis (from the 21st day on after operation) was shown, reparative fibrosis wasn’t seen. (2) Perivascular collagen area (PVCA) in the OG (2. 09 ± 0. 45) was significantly higher than SOG (0.83 ± 0.06) from the 1st day on after operation and then steadily increased, while in the OG+Li (1.16 ± 0.06), it was significantly lower than OG at the same time; collagen volume fraction (CVF) in the OG (3.08 ± 0. 56) significantly increased compared with the SOG (2. 78 ± 0. 64) from the 2nd day on after operation and showed a trend of rapid ascending from the 21st day on after operation; and in the OG + Li (4.69 ± 0.85), it was significantly decreased compared with the OG (7.56 ± 0.88) from the 21st day on after operation, with allP<0. 05.Conclusion: Ligustrazine could alleviate and postpone the accumulation of myocardial collagen and has protective effects on the heart.

Dibenzoylmethanatoboron difluoride (DBMBF2), the BF2complex of dibenzoylmethane, reacted from its singlet excited state with α,β-unsaturated ketones and esters to give 1,5-diketones by a [2+2] cycloaddition and ring-opening sequence in an analogous pathway to that observed in the photocycloaddition to olefins and dienes. The present photoreaction is unexpected since conjugated enones and en-esters are poor electron donors to comply with the previously proposed charge transfer requirement in DBMBF2photoreactions. The photocycloaddition to these substrates was highly regioselective and stereoselective, giving the head-to-head orientation, which could be enhanced by α-methyl substitution; β-methyl substitution increased the alternate head-to-tail orientation. The photolysis of a mixture of DBMBF2and a cyclic enone also caused the latter to dimerize to give head-to-head and head-to-tail dimers in significant yields. These photodimerizations were apparently caused by DBMBF2sensitization. The mechanism of the sensitization is discussed.

The catalyst and the solvent can be recycled and reused for at least five times without significant loss of activity and stereoselectivity.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.