Search

Concrete is the most commonly used construction material. However, its production leads to high carbon dioxide (CO2) emissions and energy consumption. Therefore, developing waste-substitutable concrete components is necessary. Improving the sustainability and greenness of concrete is the focus of this research. In this regard, 899 data points were collected from existing studies where cement, slag, fly ash, superplasticizer, coarse aggregate, and fine aggregate were considered potential influential factors. The complex relationship between influential factors and concrete compressive strength makes the prediction and estimation of compressive strength difficult. Instead of the traditional compressive strength test, this study combines five novel metaheuristic algorithms with extreme gradient boosting (XGB) to predict the compressive strength of green concrete based on fly ash and blast furnace slag. The intelligent prediction models were assessed using the root mean square error (RMSE), coefficient of determination (R2), mean absolute error (MAE), and variance accounted for (VAF). The results indicated that the squirrel search algorithm-extreme gradient boosting (SSA-XGB) yielded the best overall prediction performance with R2values of 0.9930 and 0.9576, VAFvalues of 99.30 and 95.79, MAEvalues of 0.52 and 2.50, RMSEof 1.34 and 3.31 for the training and testing sets, respectively. The remaining five prediction methods yield promising results. Therefore, the developed hybrid XGB model can be introduced as an accurate and fast technique for the performance prediction of green concrete. Finally, the developed SSA-XGB considered the effects of all the input factors on the compressive strength. The ability of the model to predict the performance of concrete with unknown proportions can play a significant role in accelerating the development and application of sustainable concrete and furthering a sustainable economy.

In the industrial sphere, mixed-flow centrifugal pumps are widely used to convey acids, alkalis, brines, petroleum and other media. Their performance has a significant impact on the production efficiency of industrial systems. This paper presents an analysis of the influence of positive pre-rotation on the hydraulic performance and energy conversion characteristics of mixed flow pumps under off-rated flow conditions. The accuracy of the numerical methods adopted in this study was validated by experiments, with less than 5% error observed in head and efficiency between the experimental and numerical results at rated flow condition. The influence of positive pre-rotation on the pump’s performance was found to be contingent upon the prevailing flow conditions. Under part-load flow conditions, positive pre-rotation improved the match between the medium inlet angle and blade inlet angle, leading to a reduction of the high vorticity area near the blade inlet, and consequently an improvement of hydraulic performance. However, under overload flow conditions, positive pre-rotation causes a further increment in the difference between the media inlet angle and the blade inlet angle. An increase in the secondary flow intensity within the impeller is induced, which leads to flow instability and ultimately to significant energy losses. These findings contribute to the theoretical basis for the prediction of mixed flow pump performance and operational stability improvement under off-rated flow conditions.

Molting is a key solution to growth restriction in insects. The periodic synthesis and degradation of chitin, one of the major components of the insect epidermis, is necessary for insect growth. MicroRNA (miRNA) have been implicated in molting regulation, yet their involvement in the interplay interaction between the chitin synthesis pathway and 20-hydroxyecdysone signaling remains poorly understood. In this study, soluble trehalase (Tre1) and phosphoacetylglucosamine mutase (PAGM) were identified as targets of conserved miR-8-3p and miR-2a-3, respectively. The expression profiles of miR-8-3p-SfTre1and miR-2a-3-SfPAGMexhibited an opposite pattern during the different developmental stages, indicating a negative regulatory relationship between them. This relationship was confirmed by an in vitro dual-luciferase reporter system. Overexpression of miR-8-3p and miR-2a-3 by injection of mimics inhibited the expression of their respective target genes and increased mortality, leading to death in the pre-molting, and molting death phenomena. They also caused a decrease in chitin content and expression levels of key genes in the chitin synthesis pathway (SfTre1, SfTre2, SfHK, SfG6PI, SfGFAT, SfGNA, SfPAGM, SfUAP, SfCHS1, SfCHS1a, and SfCHS1b). Conversely, the injection of miRNA inhibitors resulted in the upregulation of the expression levels of these genes. Following 20E treatment, the expression levels of miR-8-3p and miR-2a-3 decreased significantly, while their corresponding target genes increased significantly. These results indicate that miR-8-3p and miR-2a-3 play a regulatory role in the molting of Sogatella furciferaby targeting SfTre1and SfPAGM, respectively. These findings provide new potential targets for the development of subsequent new control strategies.Graphical Abstract

The utilization of recycled aggregates (RA) for concrete production has the potential to offer substantial environmental and economic advantages. However, RA concrete is plagued with considerable durability concerns, particularly carbonation. To advance the application of RA concrete, the establishment of a reliable model for predicting the carbonation is needed. On the one hand, concrete carbonation is a long and slow process and thus consumes a lot of time and energy to monitor. On the other hand, carbonation is influenced by many factors and is hard to predict. Regarding this, this paper proposes the use of machine learning techniques to establish accurate prediction models for the carbonation depth (CD) of RA concrete. Three types of regression techniques and meta-heuristic algorithms were employed to provide more alternative predictive tools. It was found that the best prediction performance was obtained from extreme gradient boosting-multi-universe optimizer (XGB-MVO) with R2value of 0.9949 and 0.9398 for training and testing sets, respectively. XGB-MVO was used for evaluating physical laws of carbonation and it was found that the developed XGB-MVO model could provide reasonable predictions when new data were investigated. It also showed better generalization capabilities when compared with different models in the literature. Overall, this paper emphasizes the need for sustainable solutions in the construction industry to reduce its environmental impact and contribute to sustainable and low-carbon economies.

Immune checkpoint blockades have been widely used to treat various malignancies. Programmed cell death protein 1 (PD-1) inhibitor-induced alopecia areata, one of the immune-related adverse events, is rarely reported. We present a case of alopecia universalis during the treatment of Sintilimab, a monoclonal anti-PD-1 antibody, in a patient with hepatocellular carcinoma. A 65-year-old male was diagnosed with hepatocellular carcinoma in liver segment VI (S6) and chose to receive Sintilimab due to predicted insufficient residual liver volume for hepatectomy. He presented extensive hair loss in all the parts of the body 4 weeks after Sintilimab treatment. And without using any dermatologic drug, the alopecia areata gradually developed to be alopecia universalis after Sintilimab continuous treatment for 21 months. The pathological examination of skin revealed remarkable increased lymphocytes infiltration around the hair follicles, which contained predominantly CD8 positive T cells in the dermis. During single immunotherapy, the tumor marker of serum alpha-fetoprotein level soon decreased from 512.1 mg/L to a normal level within 3 months, accompanied with a remarkable tumor regression in liver S6 by magnetic resonance imaging scans. The patient received hepatectomy and pathological examination demonstrated the nodule was full of extensive necrosis. By combining immunotherapy and hepatectomy, the patient finally achieved a remarkable anti-tumor effect of complete remission. Immune checkpoint blockades-induced alopecia areata is a rare immune-related adverse event and accompanied with a good anti-tumor efficacy in our case. Regardless of alopecia treatment, PD-1 inhibitor treatment is recommended to be continued, especially when the immunotherapy is effective.

The problem of decreasing stability margins in L1adaptive control systems is discussed and an out-of-loop L1adaptive control scheme based on Lyapunov’s stability theorem is proposed. This scheme enhances the effectiveness of the adaptation, which ensures that the system has sufficient stability margins to achieve the desired performance under parametric uncertainty, additional delays, and actuator faults. The stability of the developed control system is demonstrated through a series of simulations. Compared with an existing control scheme, the constant adjustment of the stability margins by the proposed adaptive scheme allows their range to be extended by a factor of 4–5, bringing the stability margin close to that of variable gain PD control with adaptively scheduled gains. The engineered practicability of adaptive technology is verified. A series of flight tests verify the practicability of the designed adaptive technology. The results of these tests demonstrate the enhanced performance of the proposed control scheme with nonlinear parameter estimations under insufficient stability margins and validate its robustness in the event of actuator failures.

Purpose: The purpose of this study is to explore the impact of environmental pollution and industrial structure upgrading on environmental pollution in different stages based on the temporal and spatial heterogeneity of economic development level and industrial structure upgrading level in eastern, central and western regions of China and discuss whether there is adjustment effect and threshold effect in the process of economic growth affecting environmental pollution, and finally realizes sustainable economic development. Design/methodology/approach: Based on panel data from 30 provincial-level administrative regions of China (excluding Tibet and Hong Kong, Macao and Taiwan) from 2000 to 2019, this paper uses the environmental Kuznets curve, regulating effect model and panel threshold model to analyze the impact of economic growth and industrial structure upgrading on environmental pollution. Findings: The results present that the uneven distribution of natural resources leads to different levels of economic development and industrial structure upgrading in eastern and western regions, and its impact on environmental pollution is also different. Economic growth and industrial structure upgrading have a positive effect on environmental pollution, and the relationship between economic growth and environmental pollution is inverted U-shaped. At present, the eastern, central and western regions of China are at the right end of the inverted U-shaped relationship. In general, industrial structure upgrading in eastern, central and western regions has a significant inhibitory effect on environmental pollution. Industrial structure upgrading has a negative moderating effect on the relationship between economic growth and environmental pollution, and the regulating effect is most significant in the central region, followed by the eastern region, and not significant in the western region. The results of panel threshold model show that the industrial structure upgrading can slow down the positive impact of economic growth on environmental pollution and strengthen the negative moderating effect of industrial structure upgrading on economic growth and environmental pollution. Originality/value: The innovation of this study is to bring economic growth, industrial structure upgrading and environmental pollution into a unified analytical framework, analyze the impact of economic development and industrial structure upgrading levels in different periods on environmental pollution, and select industrial structure upgrading as the moderating variable and threshold variable. It provides a thought for the influence mechanism of different levels of industrial structure upgrading on economic growth and environmental pollution. Based on the panel data in China, this study emphasizes the concept of sustainable development, adheres to green development and proposes relevant policies to improve environmental pollution. And this paper proposes relevant policies to improve environmental pollution from the perspective of transforming economic growth mode and optimizing industrial structure in China, which also has reference significance for developing countries to realize sustainable economic development. [ABSTRACT FROM AUTHOR]

How to reduce grade C postoperative pancreatic fistula (POPF) incidence after pancreaticoduodenectomy (PD) is the pursuit of pancreatic surgeons. This study introduced an innovative pancreaticojejunostomy (PJ) technique with a complete set of perioperative management. All 144 patients in this single-center retrospective cohort study underwent the same PJ technique and perioperative management. The primary endpoint was grade C POPF incidence. The secondary endpoints were grade B POPF rate, drain fluid amylase level, complications, hospital stay duration, and mortality. Risk factors for clinically-relevant POPF (CR-POPF) were assessed by logistic regression analysis. No patient (0.0%) experienced grade C POPF, while 44 (30.6%) developed grade B. No in-hospital death was recorded. Multivariate analysis found relatively high body mass index, laparoscopic surgery, and soft or moderate pancreatic texture independent risk factors for CR-POPF. Our novel PJ anastomosis with modified perioperative management helped avoid grade C POPF. However, grade B POPF incidence was relatively high to some extent because of the enhanced management itself.

In this article, a 2-bit wideband electronically controlled reconfigurable phased array with wide-angle beam-scanning capacity is proposed. Based on the current reversal mechanism and real-time delay design, a wideband 2-bit phase shifter is designed by cascading a wideband 180° phase shifter and a wideband 90° phase shifter. Then, a wideband 2-bit element is established by connecting the radiation area of the Vivaldi structure at the slot line of the phase shifter, and a metasurface slab with H-shaped metal layer is introduced to improve the scanning performance. Further, a planar wideband reconfigurable 2-bit array at 17 GHz has been designed and fabricated based on this element, and a stripline-based 1:16 power divider with the phase-shifting function is designed to simulate the space-fed spherical wave to avoid high sidelobe. Measured and simulated results are in good agreement. The measured results indicate that the main beam of the array can scan from $-{\mathrm {73}}^{\circ }$ to 73° at 17 GHz by appropriately controlling the state of PIN diodes, and the gain fluctuation is only 2.18 dB. The measured 3 dB gain bandwidth of the array in the broadside direction is about 29.1% (from 14.7 to 19.7 GHz). The wide-angle scanning and wideband performances are verified.

In this article, a folded low-profile wideband 1-bit reconfigurable transmitarray (RTA) with 2-D beam-scanning capacity is proposed. To reduce the profile of the whole RTA, the ray tracking mechanism and the feed optimization are introduced. A 1-bit wideband RTA element with polarization selection function and polarization rotation function is designed based on a regular hexagonal resonant patch and p-i-n diodes. Furthermore, a specially designed waveguide structure is fabricated to verify the performance of the RTA element. To achieve the low-profile design, a wideband polarization rotation reflectarray (PRRA) element acting as the reflecting surface is proposed, and a $2\times $ 2 U-slotted planar patch antenna is designed to replace the horn. With these designs, the profile can be compressed by two-thirds compared with the conventional space-fed architecture. A $16\times16$ -elements low-profile RTA is designed and fabricated. The measured and simulated radiation patterns are in good agreement. The measured peak gain is 19.6 dB, corresponding to an aperture efficiency of 13.8%, and the measured 3 dB gain bandwidth is 17.5% (from 15.1 to 18 GHz). Good scanning performance with ±60° scanning coverage in both principal planes has been obtained, and the scan losses are 3.97 and 4.15 dB, respectively. Besides, the measured sidelobe levels (SLLs) and cross-polarization levels remain better than −15 and −20 dB, respectively, at all beam directions.

To improve the heat transfer efficiency of the coolant in lead-based fast reactors, this study optimized the configuration and rotational direction of the spacer wires in fuel assemblies to design a new-pattern fuel assembly. This study conducted detailed comparisons between traditional and new pattern fuel assembly rod bundles utilizing the open-source computational fluid dynamics platform, OpenFOAM. The results indicated that the new design may significantly reduce the pressure drop along the rod bundle, which is beneficial for lowering the pressure drop. Furthermore, this new design improved coolant mixing in the subchannels, which facilitated a more uniform temperature distribution and lower thermal gradients at the assembly outlet. These factors collectively reduced the thermal fatigue and creep in nearby internal components. Overall, the new-pattern fuel assembly proposed in this study may have better heat transfer performance, thereby enhancing the Integrated Thermal-Hydraulic Factor by 48.2% compared to the traditional pattern.

In order to improve the refresh rate of large‐sized LCD products, a novel driving scheme calling Hardware Super Resolution technology or HSR for short is presented in the paper, which can be utilized in TV, MNT, NB, et al. The driving scheme mainly applied GOA Pre Charge compensation algorithm, odd and even frame interlaced time‐sharing charging and Smart TP. A protype driving circuit was fabricated, and various detection tests have been implemented. The results show the charging rate is obviously improved, and the refresh rate is doubled without increasing hardware resources.

Sublethal concentrations of insecticides can affect the population dynamics of insects by inducing changes in their reproductive traits; however, the underlying molecular mechanisms remain unclear. In previous transcriptomic experiments, triazophos was found to promote SfTOR transcription. Therefore, in this study, two representative insecticides, thiamethoxam (inhibiting reproduction) and triazophos (stimulating reproduction), were selected to evaluate the transcription of the key genes involved in the target of rapamycin (TOR) and juvenile hormone (JH) pathways under stress in Sogatella furcifera. The results showed that thiamethoxam could significantly inhibit the transcription of SfRheb, SfTOR, SfS6K, and SfHMGR, whereas triazophos significantly promoted the transcription of SfRheb, SfTOR, SfS6K, SfHMGR, SfMet, and SfKr-h1. Moreover, RNA interference (RNAi) technology was used to target and silence TOR signaling pathway-related genes. The results showed that RNAi-mediated silencing of SfRheb, SfTOR, and SfS6K significantly inhibited ovarian development and fecundity. The transcription of JH signaling pathway-related genes (i.e., SfHMGR, SfFAMeT, SfMet, and SfKr-h1) and SfVg was significantly inhibited. However, the effects of SfRheb and SfTOR silencing on female reproduction were partially mitigated by the JH analog methoprene. These results indicate that the TOR signaling pathway can regulate the JH signaling pathway and SfVg transcription. In addition, insecticide stress can influence the transcription of TOR signaling pathway-related genes and transduction of stress signals via the JH signaling pathway, thereby affecting the transcription of SfVg and ultimately regulating reproduction in females.

ATP-binding cassette transporter G1 (ABCG1) regulates cellular cholesterol homeostasis and plays a significant role in tumor immunity. But, for hepatocellular carcinoma (HCC), the role of ABCG1 has not been investigated. Thus, the aim of this study was to evaluate the prognostic value and clinicopathological significance of ABCG1 in HCC.

This paper introduces a self‐contained ultra‐large In Cell Touch driving scheme, which can be applied in 43 inch, 86 inch and larger In Cell Touch products. This driving scheme divides the VCOM electrodes in the liquid crystal cell for traditional LCD into several Sensor blocks, uses display and touch time‐sharing to drive the signal, modulates the signal in Touch stage, and uses special communication protocol to achieve simultaneous touch effect of active pen and finger.

Some veterinary drug residues in food products and environment have been widely regarded as severe threats to human health. Rapid and simultaneous detection methods are crucial to monitor and control veterinary drug usage. Here, we propose a fluorescence biosensor utilizing immunomagnetic beads (IMBs) and quantum dots (QDs) for the rapid and simultaneous detection of 1-adamantylamine (ADA), enrofloxacin (ENR) and tilmicosin (TIL) in raw chicken meat. A pretreatment method using sodium phosphotungstate–magnesium as extraction reagent was developed to simultaneously extract ADA, ENR and TIL from chicken meat with minor interference in background or response. By adding the IMBs modified with three types of antibodies and the QD-antigens modified with three types of BSA-antigens to sample, IMBs competitively conjugated to target antigens in a sample or QD-antigens. After magnetic separation, the residual QD-antigens were adopted to collect signals using fluorescence spectroscopy. Using QDs with well separated emission peaks, the detection of one type of targets was minorly interfered by the others. Under the optimum conditions, the biosensor exhibited the limit of detection of 0.96, 3.32, and 3.17 ng/mL for ADA, ENR and TIL in chicken samples, respectively, as well as good specificity. Due to the way of direct collection of signals in extracts, the tedious and complicated multiple magnetic separation and signal amplification procedures in conventional methods were avoided, thus the procedures were significantly simplified, and the reduction of the operation time of 30 min for sample pretreatment and 40 min for detection part was achieved. The biosensor might be promising in the rapid, in-field and sensitive screening of multiple veterinary drugs to ensure agriculture and food safety.

Purpose: Considering that listed companies are the main body of natural resource consumption and pollutant emission, this study aims to explore the stock price effect and source channels of green bond issuance of listed companies. This is extremely necessary to promote listed companies to actively fulfill their environmental responsibilities so as to achieve sustainable economic and social development. Design/methodology/approach: In this paper, the companies that issued green bonds in Shanghai and Shenzhen stock markets in China from 2016 to 2018 are used as samples. First of all, the authors adopt the event study method and match the two models to prove that there is a stock price effect in green bond issuance. Then, the authors introduce the general regression model to analyze the sources of the stock price effect of green bond issuance in detail through three channels: "financing cost," "investor attention" and "fundamental." Findings: In the above three channels, the "investor attention" channel can well explain the stock price effect of green bond issuance. Meanwhile, the authors also find that the stock price effect of the subsequent issuance of green bonds is more significant than that of the first time, non-financial companies are more pronounced than financial companies, public issuance are more obvious than private issuance, state-owned companies are more notable than non-state-owned companies, small-scale companies are more evident than large-scale companies and companies with high equity concentration are clearer than those with low equity concentration. Originality/value: Taking China as the research object for the first time, this paper comprehensively employs the capital asset pricing model and Fama–French five-factor model to discuss the stock price effect of green bond issuance of listed companies. Secondly, this paper also studies whether the way of green bond issuance, the type and size of the company, as well as the degree of ownership concentration will have different effects on the stock prices of listed companies. The research results provide new ideas and methods for the stock price effect of green bond issuance. [ABSTRACT FROM AUTHOR]

The conformal growth of a high-quality ferromagnet (Cr2Te3) on the nanostructures of a topological insulator (Bi2Te3) was realized via molecular beam epitaxy (MBE). A large topological Hall effect (THE) (∼400 nΩ cm) was unambiguously observed up to 95 K, which provided the evidence for the existence of magnetic spin textures such as magnetic skyrmions in this system. Detailed atomic structure characterizations revealed that black-phosphorus-like Bi nanosheets were embedded in the Cr2Te3lattice and densely stacked above the Bi2Te3nanodots. A nanoscale formation mechanism of the embedded Bi nanosheets was then proposed, demonstrating that the embedded Bi nanosheets were released from the Bi2Te3nanodots in the van der Waals epitaxy process of Cr2Te3. Remarkably, as the large spin–orbital coupling of the embedded Bi nanosheets can stimulate the generation of magnetic skyrmions at the interfaces between them and Cr2Te3, the observed large THE may be attributed to the skyrmions on the densely stacked Bi nanosheets. In summary, our findings demonstrate the reaction between transition-metal Cr and Bi2Te3in the conformal growth of Cr2Te3on Bi2Te3nanodots and provide an efficient and scalable technique to realize future spintronic devices.

Modeling for a hypersonic vehicle is a great challenging task due to its tightly integrated airframe/propulsion system and flexible structure. A three-dimensional, six-degree-of-freedom, physics-based hypersonic vehicle model is being established that can capture the real physical characteristics for control studies. Flexible effects, aerodynamic loads and viscous effects are calculated using or combining variation method, shock/expansion theory and Eckert’s reference temperature method. Based on curve fit approximation of the forces and moments of the vehicle, a control-oriented six-degree-of-freedom model is then developed. The simulations illustrate that the surrogate model contain aerodynamic/structure/propulsion interactions of the vehicle, and can support designing of the model-based control.

A micronutrient-fortified rusk for weanling children was tested in a rural area near Beijing. Two hundred twenty-six children aged 6-13 mo were randomly assigned by village to either a micronutrient-fortified or an unfortified rusk, daily for 3 mo. The fortified rusk contained extra zinc; iron; calcium; vitamins A, D, and B-12, thiamin, riboflavin, niacin, and folic acid. Infants receiving the fortified rusk exhibited no decline in hemoglobin concentrations during the study whereas those receiving the unfortified rusk exhibited a significant decline. Improvements were also seen in erythrocyte porphyrin, plasma vitamin A, and riboflavin status, but these improvements were seen in both of the groups. Micronutrient fortification was probably beneficial for iron status and the fortified rusk promises to be an effective vehicle for supplementation. Am J Clin Nutr 1993;57:506-11.

ABSTRACTVascular endothelial dysfunction is associated with the progress of many diseases. Circular RNAs (circRNAs) take part in the dysfunction of vascular endothelium. CircRNA hsa_circ_0008360 (circ_0008360) is dysregulated in high glucose-treated vascular endothelium, while the role and mechanism of circ_0008360 in high glucose-induced dysfunction remain unknown. Human umbilical vascular endothelium cells (HUVEC) were stimulated via high glucose. The abundances of circ_0008360, miR-186-5p and cyclin D2 (CCND2) were examined via quantitative real-time polymerase chain reaction or western blot. Vascular endothelial dysfunction was assessed via cell viability, apoptosis, migration and tube formation. The target relationship between miR-186-5p and circ_0008360 or CCND2 was analyzed via dual-luciferase reporter, RNA pull-down and RNA immunoprecipitation analyses. Circ_0008360 expression was enhanced in high-glucose-treated HUVEC. Circ_0008360 silence mitigated high glucose-induced suppression of viability, migration, tube formation, and increase in apoptosis in HUVEC. MiR-186-5p was sponged by circ_0008360, and miR-186-5p inhibition reversed the effect of circ_0008360 silence on high glucose-induced vascular endothelial dysfunction. MiR-186-5p alleviated high glucose-induced vascular endothelial dysfunction via targeting CCND2. CCND2 interference abolished the aggravated effect of circ_0008360 on high glucose-induced vascular endothelial dysfunction. Circ_0008360 knockdown attenuated high glucose-induced vascular endothelial dysfunction via regulating miR-186-5p and CCND2, indicating circ_0008360 might act as a target for the treatment of vascular endothelial dysfunction.Abbreviations:circRNAs, circular RNAs; HUVEC, human umbilical vascular endothelium cells; CCND2, cyclin D2; XPNPEP3, X-prolyl aminopeptidase 3; ceRNAs, competing endogenous RNAs; miRNAs, microRNAs; qRT-PCR, quantitative real-time polymerase chain reaction; RIP, RNA immunoprecipitation; HIF-1α, hypoxia inducible factor 1 alpha; TLR3, toll-like receptor 3; AKAP12, A-Kinase Anchoring Protein 12; ox-LDL, oxidized low-density lipoprotein; HG, high glucose; NG, normal glucose.

A novel strategy is developed for the facile fabrication of photocatalyst-immobilized gel beads with interconnected macropores for the efficient removal of pollutants in water via visible photocatalysis. In this study, a graphitic carbon nitride nanosheet (CNNS) is selected as the photocatalyst and calcium alginate (CaAlg) is used as the gel matrix. The interconnected macropores inside the gel beads, which are beneficial to the efficient mass transfer of pollutants, are generated using bubbles as templates. Air bubbles are wrapped in a pre-gel aqueous solution containing sodium alginate (NaAlg), CNNS, sodium dodecyl sulfate (SDS), and sodium bicarbonate (NaHCO3) by vigorously stirring the solution, and then, the foamy solution is dripped into calcium chloride/acetate acid (CaCl2/CH3COOH) mixed aqueous solution. The rapid crosslink of Ca2+with alginate turns the droplets into gel beads, and meanwhile, the macropores inside droplets become interconnected because of the rapid generation of CO2gas upon the reaction between NaHCO3and excess CH3COOH. Effects of the formulations of pre-gel solutions, including NaAlg, CNNS, NaHCO3, and SDS contents, on the structures and photocatalytic performances of gel beads are investigated systematically. Demonstrated by removing a model pollutant rhodamine B (RhB) from water, CNNS-immobilized CaAlg gel beads with interconnected macropores exhibit excellent photocatalytic performances under visible light. About 99% of RhB in water can be removed efficiently within 30 min under visible light using the as-prepared gel beads. Importantly, the proposed gel beads can be easily recycled with stable photocatalytic performances. The proposed novel strategy for fabricating photocatalyst-immobilized gel beads with interconnected macropores is highly promising and is of great reference value for the fabrication of macroporous gel beads for various applications.

The fall armyworm (FAW), Spodoptera frugiperdaSmith (Lepidoptera: Noctuidae) is an important agricultural pest that invaded China in the middle of December 2018. As a polyphagous pest, FAW is identified as a serious threat to agricultural production and food security in China. Pepper (Capsicum annuumL.), tomato (Solanum lycopersicumMill.) and eggplant (Solanum melongenaL.) are three of dominant solanaceous vegetables of this country. To our knowledge, the effects of these plants on the performances of FAW have not been well studied. In this study we assessed the fitness of this pest to these three plants. Results showed that FAW can complete its life cycle when fed with tomato and pepper, but not on eggplant. The population parameters of FAW fed with maize (Zea maysL.) and the three solanaceous vegetables were compared using the age-stage, two-sex life table method. Developmental duration was significantly different in the larval stage, but not in the pupae stage. FAW fed with pepper had the longest pre-adult period (41.73 d) and the lightest pupal weight (0.1134 g); the survival rate was lower than FAW fed with tomato. Significant differences were observed in the mean fecundity of female, with the highest (943.95 eggs) laid by FAW fed with tomato. FAW had the shortest mean generation time (T), the highest intrinsic rate of increase (r) and finite rate of increase (λ) on maize, and the highest net reproductive rate (R0) on tomato. Overall, FAW fitness on the three solanaceous vegetables was: tomato>pepper>eggplant. This study provides the foundation for further assessment of FAW risk to solanaceous vegetables and for establishing corresponding control strategies in China.

Topological Hall effect is an abnormal Hall response arising from the scalar spin chirality of chiral magnetic textures. Up to now, such an effect is only observed in certain special materials, but rarely in traditional ferromagnets. In this work, we have implemented the molecular beam epitaxy technique to successfully embed black-phosphorus-like bismuth nanosheets with strong spin-orbit coupling into the bulk of chromium telluride Cr2Te3, as evidenced by atomically resolved energy dispersive X-ray spectroscopy mapping. Distinctive from pristine Cr2Te3, these Bi-embedded Cr2Te3epitaxial films exhibit not only pronounced topological Hall effects, but also magnetoresistivity anomalies and differential magnetic susceptibility plateaus. All these experimental features point to the possible emergence of magnetic skyrmions in Bi-embedded Cr2Te3, which is further supported by our numerical simulations with all input parameters obtained from the first-principle calculations. Therefore, our work demonstrates a new efficient way to induce skyrmions in ferromagnets, as well as the topological Hall effect by embedding nanosheets with strong spin–orbit couplings.

How an interfacial superconductivity emerges during the nucleation and epitaxy is of great importance not only for unveiling the physical insights but also for finding a feasible way to tune the superconductivity via interfacial engineering. In this work, we report the nanoscale creation of a robust and relatively homogeneous interfacial superconductivity (TC≈ 13 K) on the epitaxial FeTe surface, by van der Waals epitaxy of single-quintuple-layer topological insulator Bi2Te3. Our study suggests that the superconductivity in the Bi2Te3/FeTe heterostructure is generated at the interface and that the superconductivity at the interface does not enhance or weaken with the increase of the Bi2Te3thickness beyond 1 quintuple layer (QL). The observation of the topological surface states crossing Fermi energy in the Bi2Te3/FeTe heterostructure with the average Bi2Te3thickness of about 20 QL provides further evidence that this heterostructure may potentially host Majorana zero modes.

Exploring spin-polarized two-dimensional materials with a Dirac cone is essential for potential applications in nanoscale electronics and spintronics. Herein, we report a two-dimensional structure with Ti sandwiched between α1- and β-sheet borophene, namely, Ti-BHB. Our results demonstrate that the sandwich structure is thermodynamically stable, confirmed with the calculated phonon spectra and ab initio molecular dynamics simulations at the temperature up to 1200 K. Of particular interest, Ti-BHB is spin-polarized Dirac semimetal with an antiferromagnetic ground state, which is different from most reported two-dimensional nonmagnetic Dirac materials. The Dirac state at the Fermi level arises primarily from the hybridization between Ti-dx2–y2/dxyand B-pzorbitals. Charge analysis reveals that electrons are transferred from metal atoms to the electron-deficient borophene layers. Interestingly, Ti-BHB preserves the spin-polarized Dirac cone under compressive strains up to 5%, while undergoes a semimetal-to-semiconductor transition under tensile strains within 5% along uniaxial xor biaxial xydirections. Meanwhile, Ti-BHB is completely transformed to be ferromagnetic metal under tensile strains larger than 2% along the ydirection. These novel properties render Ti-BHB great potential in electronic and spintronic device applications.

The structures and properties of one-dimensional (1D) sandwich molecular wires constructed with altering 3d transition metal (TM) and the metallofullerene (TM@C60) entities, [TM&(TM@C60)]∞, are studied using density functional theory calculations. Different from the bonding character insensitivity to TM of previously reported 1D [TMBz]∞and [TMCp]∞analogues, the bonding characters of the investigated 1D [TM&(TM@C60)]∞molecular wires depend heavily on the identity of metal elements. In 1D [TM&(TM@C60)]∞, molecular wires with early TMs like Ti and V, TM-η5coordinate bonds are favored. In contrast, TM-η6bonding conformations are energetically preferred for those with later TMs, for example, Cr–Ni. Bader charge analysis reveals that valence electrons are transferred from both encapsulated and sandwiched TM atoms to the C60ligand. More importantly, all the molecular wires in ground states are robust antiferromagnetic semiconductors because of the peierls distortion of the configurations and the moderate binding energies. Therefore, the fabrication of endohedral metallofullerenes offers an effective route to regulate the magnetism and electronic properties of C60–ligand sandwich complexes.

Due to the unique geographical location and sensitive response to global climate changes, the Antarctic region plays an important role in paleoclimate researches, and attracts great attentions from various scholars. One 324 cm long sediment core (ANT29-P7-09) was obtained from Prydz Bay, Antarctica, during the 29th Chinese National Antarctic Research Expedition. Based on sediment particle size, TOC, δ13C analyses and magnetism data, the authors show that the dominant magnetic minerals are ferrimagnetic pseudo single domain (PSD)-multi domain (MD) magnetite. Variations in the paleoenvironmental records allow us to define 4 zones in the core. These zones outline the climatic variations in the region since the late Early Pleistocene, including a warm period, a transitional period, and a cold period. The magnetic particle assemblage varies with glacial-interglacial cycles. Abrupt changes in particle size, TOC content, and geomagnetism occur at 102–90 cm deep in the core, indicating a sudden warming in the Antarctic region, signaling the onset of the Holocene. The authors identified 3 additional climatic signals in the middle part of the core (232–162 cm) that show unexpected cooling events during the warm period in Prydz Bay, Antarctica.

Eu isotopes are promising tracers across various scientific domains such as planetary, earth, and marine science, yet their high-precision analysis has been challenging due to the similar geochemical properties of rare earth elements (REEs). In this study, a novel two-column chromatographic approach was developed utilizing AG50W-X12 and TODGA resins to separate Eu effectively from matrix and interfering elements like Ba, Nd, Sm, and Gd, while ensuring high Eu yields (99.4 ± 0.4%, n= 19) and low blanks (<20 pg). The robustness of this method is evidenced by various rock types and different Eu loading masses. The efficient purification of Eu facilitated the establishment of a high-precision calibration technique with standard-sample bracketing (SSB) and internal normalization (Nd). When a Nu Plasma 1700 multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) instrument was employed, repeated purification and analysis of various Geological Reference Materials (GRMs) confirmed that the long-term external precision of δ153/151Eu is better than 0.04‰ (2 standard deviation (2SD)), which represents a 2–5-fold increase in precision compared to previously reported methods. Additionally, the high-precision Eu isotopic compositions of five GRMs, including basalts, andesite, syenite, and marine sediment, were measured. The high-precision Eu isotope techniques presented herein open up new avenues for Eu isotope geochemistry.

Structure–activity relationship of mechanophores has always been a research focus in the field of polymer mechanochemistry. Here, we report our investigation of the effects of substitution and pulling geometry on the mechanochemical reactivity of anthracene–maleimide Diels–Alder (DA) adducts. The results of both ultrasonication experiments and constrained geometries simulate external force (CoGEF) calculations show that the adducts with the same pulling points at the 9-position of anthracene and the Natom of succinimide but different substituents (e.g., H, alkylthio, or dialkylamino) at the succinimide C2 position can be mechanochemically activated and undergo a retro-DA reaction under applied force with similar reactivity, implying that substitution in the succinimide C2 position has an insignificant effect on the mechanochemical reactivity. Remarkably, the adduct with one of the pulling points changed from the Natom to the C2 substituent of the succinimide becomes mechanochemically inert due to weak mechanochemical coupling associated with poor orientational alignment between the “scissile” bond and the pulling vector.

The heterostructures of the ferromagnet (Cr2Te3) and topological insulator (Bi2Te3) have been grown by molecular beam epitaxy. The topological Hall effect as evidence of the existence of magnetic skyrmions has been observed in the samples in which Cr2Te3was grown on top of Bi2Te3. Detailed structural characterizations have unambiguously revealed the presence of intercalated Bi bilayer nanosheets right at the interface of those samples. The atomistic spin-dynamics simulations have further confirmed the existence of magnetic skyrmions in such systems. The heterostructures of ferromagnet and topological insulator that host magnetic skyrmions may provide an important building block for next generation of spintronics devices.

The flow pattern of supercritical flow in bend channels is complicated due to the shock wave phenomenon, which creates difficulties with regard to research and design of bend channels. Using the spillway of an actual project as an example, a three-dimensional numerical investigation was conducted to simulate the flow in a steep-slope bend based on the renormalization group (RNG) k-εturbulence flow model and the volume of fluid (VOF) method. The validity of the numerical simulation was demonstrated by comparison between the results of numerical simulation and physical model tests. An optimal scheme of setting vertical vanes in the bend channel is presented. The results of numerical simulation and physical model tests are in agreement, which demonstrates the effectiveness of optimization of vertical vanes and the validity of the three-dimensional numerical simulation. Water depths along both bend walls were analyzed numerically and theoretically. The formula for calculating supercritical water depth along either bend wall was derived, and the critical condition of flow separation from the inner wall was determined.

In this paper, an integrated processing method was demonstrated to fabricate the polymer-based thermo-optic (TO) switch with low power consumption. The characteristic parameters of the switch were carefully designed and simulated. The air trench structure was exploited to reduce the power consumption, which can be formed with the waveguide simultaneously by the integrated processing method. Moreover, the introduced polymer/silica hybrid waveguide structure can also improve the response time of the device. A typical fabricated switch presented a low switching power of 5.2 mW. The measured switching rise time and fall time are 192.2 and 201.1 μs, respectively.

Diamond cutting is a popular method to fabricate microlens array (MLA) on polymethyl methacrylate (PMMA); however, it is limited by brittle fracture, which is formed easily on the surface of MLA during the cutting process. In this paper, the formation mechanism of the brittle fracture is studied via a series of experiments including the slow tool servo (STS) cutting experiment of MLA, surface scratching experiment and sudden-stop cutting experiment. The effects of undeformed chip thickness, feed rate, and machining track on brittle fracture formation are investigated in detail. In addition, based on the fracture formation mechanism, a bi-directional cutting approach is proposed to eliminate the regional brittle fracture of the microlens during diamond cutting. An experiment was then conducted to verify the method; the results demonstrated that bi-directional cutting could eliminate brittle fracture entirely. Finally, a spherical MLA with the form error (vPV) of 60 nm and the surface roughness (Ra) of 8 nm was successfully fabricated.

Before the India-Asia collision, Neotethyan subduction gave rise to an Andean-type convergent margin on the southern margin of Asia. To investigate the spatial and temporal distribution of the subduction-related magmatism, we undertook a combined determination of zirconU-Pb ages and Hf isotopes of Mesozoic to Paleogene intrusive and volcanic rocks from southern Tibet to Myanmar to characterize the two parallel magmatic belts that have previously been considered separately. One belt extends from the Gangdese Batholith in the Southern Lhasa sub-terrane to the Lohit Batholith, the Sodon Pluton and the Popa-Loimye Arc in theWest Burma Block, and the other from the Central Lhasa Plutonic Belt to the Bomi-Chayu Batholith, the Dianxi Batholith and the Shan Scarps Batholith in central Myanmar. The Gangdese belt, as the main arc component, consists typically of I-type granitoids that contain magmatic zircons showing positive eHf(t) values. In contrast, the Central Lhasa Plutonic Belt belt is dominated by S-type granites in which most zircons show negative eHf(t) values suggesting the involvement of older continental crust in their petrogenesis. The distinct geochemical characteristics indicate not only distinct tectonic settings of their genesis but also the diverse nature of the crust forming the exotic continental ribbons amalgamated to Asia. [ABSTRACT FROM AUTHOR]

For a new kind of dual-spin spacecraft mission which is used for earth-observation, a method to manage the rotor's angular momentum with magnetic torquers is introduced in this paper. Three magnetic torquers fixed on the rotor part produce periodic magnetic momentum which contracts with Earth's magnetic field, balancing the angular momentum caused by friction of bearing while no angular momentum accumulation is caused to the other two axes. This method is applicable in engineering. Simulation shows that the total angular momentum of rotor converges to the desired value and does not accumulate over time. [ABSTRACT FROM AUTHOR]

Surfactant flooding has been widely applied in high-temperature and high-salinity reservoirs. In this paper, the enhanced oil recovery potential of alkyl alcohol polyoxyethylene ether sulfonate (CEOS) was investigated in a combined study of surface activity, crude oil–water interfacial tension (IFT) reduction, emulsifying property, wettability improvement, and macroscopic oil displacement efficiency. The results illustrated that CEOS had high surface activity and IFT could be reduced to an ultralow level (10–3mN/m) at high-temperature and high-salinity conditions. When salinity ranged from 15 × 104to 22.5 × 104mg/L and reservoir permeability was ∼10 mD, linear CEOS solution could effectively displace crude oil for its favorable IFT reduction ability. Linear CEOS or CEOS with a benzene ring was optimized for their favorable IFT reduction ability or emulsifying ability when reservoir permeability was ∼50 mD or non-homogeneous. A 0.5 pore volume surfactant flooding and subsequent water flooding could remarkably enhance oil recovery to 16.19–19.38%. All of the results indicated that CEOS has great potential for improving oil recovery in high-temperature and high-salinity oil reservoirs.

In order to control the quality of spline shaft in rolling process, an efficient measurement method for rolling performance evaluation is essential. Here, a newly developed on-machine non-contact measurement prototype based on laser displacement sensor and rotary encoder is proposed. The prototype is intended for the automated evaluation of the spline shaft rolling performance by measuring the dimensional change of tooth root, which is correlated with the surface residual stress and micro-hardness. Laser displacement sensor and rotary encoder are used to record the polar radius and polar angle of each point on measuring section. Data are displayed in a polar coordinate system and fitted in a gear. Through multipoint curvature method, the roots of spline shaft are recognized automatically. Then, the dimensional change can be calculated by fitting the radius of the tooth root circle before and after rolling. Systematic error covering offset error is also analyzed and calibrated. At last, measurement test results show that the system has advantages of simple structure, high measurement precision (radius error < 0.6 μm), high measurement efficiency (measuring time < 2 s) and automatic control ability, providing a new opportunity for the efficient evaluation of various spline shafts in high-precision mechanical processing.

Mining activities tend to generate various waste including tailings, waste water and waste rock. Efficient management and disposal of these waste materials are critical to minimize their environmental impact and ensure the sustainable operation of mining activities. A huge number of tailings are produced all around the world each year. Generally, part of the tailings is used for underground backfilling and another part is discharged to the tailings dam. The former can provide underground support while the latter tends to cause some environmental problems because the tailings are generally mixed with some chemicals. Regarding this, enhancing the circular use of tailings is crucial to guarantee the sustainable mining engineering. In this study, the feasibility of using fine-grained tailings to make non-burning hollow bricks for underground windbreaks is investigated. A two-stage experiment was implemented where the first stage experiment indicated the threshold of water content, the ratio of cement and tailings and the ratio of fine-grained and rod-mill tailings. In addition, it can be indicated that the addition of polyethylene fibers would increase the compressive strength of hollow bricks in some extent. The second-stage experiment was conducted with no rod-mill tailing added and it can be found that when the ratio of cement and tailings is equal or higher than 1:6, fiber content is more significant in improving brick strength but when this value is lower, the ratio of cement is more important than fiber factors. When the ratio of cement and fine-grained tailings is 1:8 with 0.5 g/kg and 12 mm polypropylene fiber added, the hollow brick is capable of achieving strength of 1.4 MPa for 28 days curation with the price of 0.50 RMB/block. This proportioning scheme is the least expensive while meeting the strength of the windbreak wall for the Fan Kou lead–zinc mine. Finally, it can be indicated that the usage of fine-grained tailings to make underground windbreak wall is feasible and thus provide a new scenario to circular usage of tailings. In addition, other proportioning schemes proposed in this study perhaps can meet more engineering requirements so as to provide more alternatives for circular use of tailings.

In this paper, the chromatic of black matrix after sunlight aging in the process of OGS ( one glass solution ) touch panel manufacturing was studied. The NG area was judged by appearance and metallographic microscope. Different etching time and UV light on the influence of the black matrix was designed to measure the reflectance, transmittance and optical density, etc. The thermal decomposition temperature and glass transition temperature were characterized by thermo gravimetric and differential thermal (TG‐DSC) analysis. The BM material in the glass surface summoned up. It could be observed by scanning electron microscope (SEM). In addition, the theory on chromatic of BM after sunlight aging was proposed. Acrylic material would degrade under UV irradiation, and H icon in the etching paste promoted the reaction.

In view of the fact that the effect of ITO index matrix simulation cannot be obtained directly and accurately in the past research, this paper establishes an ITO IMQS (index matrix quantitative simulation) model in human vision. The ITO IMQS model can be used to obtain the data and pictures of characterization effect of index matrix directly which is based on the theory of the Radiation energy flux and Luminous flux. According to the consequence of calculation and comparison, the model simulation results with the actual situation is consistent, fully shows highly validity of the model. The ITO IMQS model completely solves the problem of ITO index matrix in the early stage of product design, and it also provides great convenience for the timely and effective improvement scheme of the products already in question.

TiC base high manganese steel-bonded carbide was manufactured by powder metallurgy technique, and the effect of adding mode of WC additive on microstructural evolution and properties of the alloy was studied. SEM microstructure showed that surrounding structure appeared obviousely with WC additive; while microstructure of the alloy was well-distributed and particle shape was distinct very much. The shape of TiC particles became irregular with pure WC powder addition, and irregular with further increase of WC content, and the shape of some TiC particles became angular because of excessive reaction between TiC particles and WC additive. microstructure of the alloy was refiner and the strength, toughness were improved with the increase of WC addition. (Ti, W)C solid solution is superior to form on the surface of TiC particles through dissolution precipitation mechanism because the activity energy of WC was higher than that of TiC-WC compound carbides when WC was added in the alloy, and the particle shape of TiC became more irregular and the properties were improved significantly.

In this paper, the reliability of thermoplastic ACF in the process of OGS touch panel manufacturing was studied. The fourier transform infrared spectroscopy (FTIR), volume removal gel permeation chromatography (GPC) and weighing method research were used to characterize the structure of functional group, molecular weight and the change of absorption rate of ACF colloid materials under different curing condition. The thermal decomposition temperature and glass transition temperature were characterized by thermo gravimetric and differential thermal (TG-DSC) analysis. The effect of high temperature and high humidity on the bond strength of ACF was studied by the failure test of adhesion mode. The results showed that, under high temperature and high humidity environment, because of the erosion of water molecules, the plasticity of ACF materials became stronger, the glass transition temperature (Tg) decreased and the thermal stability became worse. As a result, the bond strength of the material was greatly influenced by the humidity. In addition, the comparison of different aging time pull out force test after the thermoplastic ACF sample scanning electron microscope (SEM) images could be indicated that the peeling effect of ACF with damp heat aging time was more and more obvious.

In this paper, two ESD phenomenon of OGS touch panel were analyzed, that are electrostatic breakdown of black matrix and bridge. Firstly analyzed the principle of electrostatic breakdown of black matrix and metal bridge. Then, Using two-level factorial designs methods, take the ESD ability of glass surface and sensor surface as response variables, these influence parameters were optimized with factors of cost, transmittance, electrical uniformity etc. and obtained the optimal parameter combination is SiO2 thickness 400 Å,ITO space 100pm, bridge width 10µm, OC2 thickness 2.0µm. Experiment results show that, using the optimized parameters, the ESD ability of glass surface by the original 7 kV up 10 23 kV and sensor surface by the original 2 kV up to 7 kV, as well as, the electrical properties and optical property are all spec in.

Sulforaphane is a common antioxidant selectively abundant in cruciferous plants, which exhibits effective anti-cancer actions in control of tumorigenesis or progression of various cancers. A recent study has shown that sulforaphane attenuates the EGFR signaling pathway in non-small cell lung cancer (NSCLC), suggesting its potential anti-metastatic effects. In this study we assessed the involvement of sulforaphane and miR-616-5p in epithelial-mesenchymal transition (EMT) and NSCLC metastasis. Sulforaphane suppressed the cell proliferation in human NSCLC cell lines H1299, 95C and 95D with IC50values of 9.52±1.23, 9.04±1.90 and 17.35±2.03 μmol/L, respectively. At low concentrations (1–5 μmol/L), sulforaphane dose-dependently inhibited the migration and invasion of 95D and H1299 cells with relatively high metastatic potential. The anti-metastatic action of sulforaphane was confirmed in 95D and H1299 cell xenografts in vivo. In fresh NSCLC tissue samples from 179 patients, miR-616-5p levels were upregulated in late-stage NSCLCs, and strongly correlated with risk of NSCLC recurrence and metastasis. Consistent with the clinic observation, miR-616-5p levels in the 3 NSCLC cell lines were correlated with their metastatic ability, and were decreased by sulforaphane treatment. Silencing miR-616-5p markedly suppressed the migration and invasion of 95D cells in vitro and NSCLC metastasis in vivo. Further studies revealed that miR-616-5p directly targeted GSK3β and decreased its expression, whereas sulforaphane decreased miR-616-5p levels by histone modification, and followed by inactivation of the GSK3β/β-catenin signaling pathway and inhibition of EMT, which was characterized by loss of epithelial markers and acquisition of a mesenchymal phenotype in NSCLC cells. Our findings suggest that sulforaphane is a potential adjuvant chemotherapeutic agent for the prevention of NSCLC recurrence and metastasis, and miR-616-5p can be clinically utilized as a biomarker or therapeutic target to inhibit metastasis.

Drill flute has a great influence on the drilling performance of micro-drill, and its profile largely depends on the grinding parameters, wheel profile and position. It is promising to obtain a desired flute profile with a standard wheel by adjusting the wheel position parameters. To investigate the influence of wheel position parameters on the flute profile, the micro-drill flute is simulated by MATLAB software considering the wheel installation angle and the offset distance from wheel origin to the drill blank origin, and the radial rake angle, flute width and chip evacuation capacity are quantitatively calculated to evaluate the flute profile. The simulated results show that the wheel installation angle has an obvious effect on the three performance parameters of flute profile, and the wheel offset distance only influences a parameter, i.e., the flute width evidently. The radial rake angle of drill flute increases obviously with the increased wheel installation angle, and decreases slightly with the increased wheel offset distance. With the decreased wheel installation angle, the flute width of drill flute increases causing the reduction of micro-drill strength but improvement of the chip evacuation capacity. With the increased wheel offset distance, the flute width also increases resulting in the reduction of micro-drill strength but no obvious change on chip evacuation capacity. Thus the wheel installation angle can be used as a main factor among the wheel position parameters to obtain the desired flute profile.