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Summary Ethyl carbamate (EC) concentration is an important indicator of the safety of rice wine. In this study, the effects of replacing traditional starters with synthetic starters on the quality of rice wine were studied to provide a basis for the application of laboratory strains to explore the metabolic basis of EC formation in rice wine fermentation systems. The effects of synthetic starters on the physicochemical indices, free amino acids, flavour compounds, urea and EC of rice wine were studied. The results showed that the microorganism species and inoculation fermentation method strongly influenced the physicochemical and flavour properties of the rice wine, among which continuous co‐fermentation improved the mellowness and flavour of the rice wine. The concentrations of urea and EC in rice wine fermented with synthetic starters decreased significantly compared with those in the control group, in which the urea content decreased by up to 97.4% and the EC content decreased by up to 90.9%. In addition, the flavour compound data showed that the differences in the aromas of rice wine fermented with different starters were mainly due to the differences in the contents of alcohols and esters. These findings suggest that EC can be regulated by changes in starters and provide guidance for the optimal configuration of mixed fermentation systems. [ABSTRACT FROM AUTHOR]

Objective: We investigated heterosexual and nonheterosexual Chinese international students' views about cooperative marriages and romantic relationships. Background: Cooperative marriages and romantic relationships are those in which two partners, one or both of whom self‐identify as nonheterosexual, consent and pretend to be a heterosexual couple as a means of relieving social pressures that require involvement in heterosexual relationships (Kam, 2013). Method: In total, 265 Chinese international students (Mage = 23 years) participated in an online survey; 210 self‐identified as heterosexual and 55 as members of sexual minority groups. Results: Students who identified as members of sexual minority groups reported few aspirations and unfavorable attitudes toward cooperative marriages and relationships. Of the students identifying as members of sexual minority groups, those who envisioned future residence in foreign countries reported fewer aspirations for such relationships than their nonheterosexual peers who anticipated returning to China. Moreover, regardless of sexual identities, students who reported higher endorsement of traditional cultural values held less negative attitudes toward such relationships. For students who identified as members of sexual minority groups, stronger acculturation to the U.S. culture was associated with more negative attitudes toward such relationships. Conclusion: Our study found that Chinese international students identifying as members of sexual minority groups held unfavorable views about cooperative marriage and it highlighted the role of transnational mobility and cultures in these views. Implications: Our study implied the importance of cultural responsiveness in how health practitioners could better support individuals of diverse sexual identities and cultural backgrounds. [ABSTRACT FROM AUTHOR]

Water deficit and soil salinization are the primary abiotic stress factors hindering maize growth. To assess the effect of water and salt stress on xylem embolism in maize and investigate the relationship between drought resistance and xylem vulnerability, a greenhouse experiment was designed using two maize cultivars, Zhengdan 958 (drought-resistant) and Denghai 605 (drought-sensitive). Four treatments were included: control (CK), water deficit (WD), salt stress (SS), and combined water and salt stress (WS). Various hydraulic characteristic indicators, such as stem xylem water potential, leaf xylem water potential, the specific hydraulic conductivity ( K s ) and percentage loss of conductivity (PLC), were analyzed. Specific hydraulic conductivity curves and vulnerability curves were constructed, and the hydraulic safety margin (HSM) of the xylem was determined based on stomatal conductance ( G s ). The results indicated that the hydraulic conductivity and embolism resistance of maize xylem were not correlated. Compared to Denghai 605, Zhengdan 958 had lower maximum specific hydraulic conductivity K s m a x and P 50 values (xylem water potential at 50% PLC) in all treatments, indicating lower water transport capacity but stronger resistance to embolism. Under single-cultivar conditions, salt stress had a greater inhibitory effect on K s m a x and HSM in maize xylem compared to water deficit; thus, more severe embolism was found under salt stress. Under different treatment conditions, Zhengdan 958 had a larger HSM than Denghai 605, showing a wider water transport safety range and overall superior water transport security. To summarize, water and salt stress inhibited the water transport efficiency of the xylem in maize stems, and stronger drought-resistant cultivars showed greater resistance to embolism and larger hydraulic safety margins. [ABSTRACT FROM AUTHOR]

Some bi/multi‐stable mechanical meta‐structures are implemented as mechanical memory devices, which are with limits such as complex structural forms, low information storage capability and/or fragile structural stability to maintain the stored information bits robustly under external interferences. To address these issues, the structural intelligence is addressed by constructing a simple 3D‐printable multi‐layered cylindrical kirigami module with gradient structural parameters and a high‐efficiency mechanical memory device that can robustly store information bits exponentially larger than previous designs is proposed. The promising enhancement of information storage capability is demonstrated for the proposed mechanical memory device and relies on two mechanisms: 1) the deformation sequences of the kirigami module enabled by the gradient structural parameter, which brings the extra dimensional degree of freedom to break the traditional mechanical memory unit with only planar form and merits information bits with spatially combinatorial programmability, and 2) the combinatorics of the deformation independences among the cylindrical kirigami unit arrays in the constructed mechanical memory device. Particularly, both the structural stabilities and the desired structural robustness are achieved in the mechanical memory devices by additively introducing magnetic "N–S" poles in units, which can protect the stored information from interferences like mechanical crushing, impact, and/or vibration. [ABSTRACT FROM AUTHOR]

Phosphor conversion materials with excellent thermal stability and broad-spectrum is critical to obtaining laser lighting devices with high luminous flux and CRI. In this paper, high thermally stable green AlN-Lu 3 Al 5 O 12 :Ce (ASL) and red AlN–CaAlSiN 3 :Eu (ASR) composite phosphor ceramics were prepared by embedding phosphor into AlN ceramic matrix. With mass ratio of phosphor increasing, luminescence intensity and quantum efficiency gradually increased, and the maximum internal quantum efficiency reached 62.8 % and 78.9 % for ASL and ASR, respectively. Under laser exciting in reflection mode, ASL-20 and ASR-50 got the max luminous emittance of 2827.5 lm/mm2 and 268.7 lm/mm2 with a saturation laser power density of 60.4 W/mm2 and 16.7 W/mm2, respectively. The diffusion coefficient of Ca, Al, Si between AlN and CASN grains was 2–4 magnitude higher than that of Lu, O, N between AlN and LuAG grains, confirming facile solid solubility of AlN and CASN. Finally, luminescence performances of green-red color wheel fabricated by ASL and ASR were evaluated. When the area ratio of green to red was 2:1, the color wheel yielded the biggest CRI of 82.6. This work presents a facile strategy for fabricating high thermally stable AlN-based composite phosphor ceramic and its application in high-quality laser lighting and display devices. [ABSTRACT FROM AUTHOR]

Federated learning enables a large number of clients (such as edge computing devices) to learn a model jointly without data sharing. However, the high amount of communication of the federated learning aggregation algorithm hinders the realisation of artificial intelligence in the last mile. Although FederatedAveraging (FedAvg) is the leading algorithm, its communication cost is still high. The method of communication delay and gradient sparse can reduce the communication cost, but there is no previous work to analyse the relationship and common effects of these two dimensions. Aiming at the problems that federated learning communication is expensive and it has become a training bottleneck, we improve the FedAvg algorithm and propose an adaptive communication frequency FederatedAveraging algorithm (AFedAvg). The gradient sparse operation in the algorithm reduces the quantity of parameters for a single communication, while the communication delay operation allows training to converge faster and obtain smaller losses. The number of sparse parameters is used to select the communication frequency of next round dynamically. Experimental results prove that, the AFedAvg algorithm is superior to the FedAvg and its variants in terms of communication cost. It achieves 2.4X–23.1X communication compression in different data distributions with minimal communication rounds required by the algorithm to converge. [ABSTRACT FROM AUTHOR]

This paper presents a multi-objective robust optimization method for a drive system consisting of a permanent magnet transverse flux machine with soft magnetic composite cores and a field-oriented controller. Unlike existing research work, the torque ripple is considered an optimization objective. Several machine uncertainties caused by manufacturing tolerances are investigated in the robust optimization model under the framework of the design for six-sigma. Since this is a system-level optimization problem, two approximation models are employed to decrease the computational cost. First, a Kriging model is used to approximate the steady-state electromagnetic performances of the motor, such as the output power and efficiency. Second, a Taylor series approximation is employed to estimate the dynamic performances of the control system, such as the speed overshoot and settling time. Furthermore, a sampling selection method is proposed to reduce the computational cost of the Monte Carlo analysis in robust optimization. To show the effectiveness of the proposed method, both deterministic and robust Pareto solutions are presented and discussed. It can be seen that the system-level multi-objective design optimization based on robust approach can produce optimal Pareto solutions with a high manufacturing quality for the whole drive system. This is valuable for the batch production of electrical drive systems. [ABSTRACT FROM AUTHOR]

Summary: The starters (Jiu Yao) play key roles in the fermentation of rice wine. However, the microbial composition in the starters and their impact on the dynamic changes in the microbial community during the fermentation of Chinese rice wine (CRW) remain unknown. This study aimed to investigate the microbial community structure in different stages of CRW fermentation with two starters (Q1 and Q2) using high‐throughput sequencing approaches. The β‐diversity analysis showed significant differences in fungal components during fermentation, but no significant differences in bacterial composition. Saccharomyces, Aspergillus, Wickerhamomyces and Hyphopichia were the dominant fungal genera. Pediococcus and Weissella were the main bacterial genera. In addition, the ethanol content of wine fermented with Q1 starter (13.33%) is not as high as that of wine made with Q2 starter (14.57%). The total sugar concentration of Q1 and Q2 starters fermentation broth (HJ‐1 and HJ‐2) is 22.74 and 30.20 g L−1, respectively. The correlation analysis showed 11 dominant microbial genera are strongly related to 27 volatile compounds in HJ‐1, and seven dominant microbial genera are strongly related to 18 volatile compounds in HJ‐2. In conclusion, this study indicated that CRW brewed with different starters have different flavour profiles. [ABSTRACT FROM AUTHOR]

A strong link between children's emotion regulation and oppositional defiant disorder (ODD) symptoms has been documented; however, the within-person mechanisms remain unclear. Based on the self-control theory and self-regulation theory, our study investigated the longitudinal, bidirectional relationship between emotion regulation and ODD symptoms in school-age children with ODD using parent- and teacher-reported data, respectively. A total of 256 Chinese elementary school students participated in a three-wave longitudinal study spanning two years. We used the random intercept cross-lagged panel model (RI-CLPM) to investigate the concurrent and longitudinal associations between emotion regulation and ODD symptoms. Results from the RI-CLPMs revealed that ODD symptoms were negatively correlated with emotion regulation and positively correlated with emotion lability/negativity at both the between-person and within-person levels across settings. Additionally, in the school setting, emotion regulation negatively predicted subsequent ODD symptoms but not vice versa, whereas emotion lability/negativity was bidirectionally associated with ODD symptoms over time. The longitudinal associations of ODD symptoms with emotion regulation and lability/negativity were not observed in the home setting. These findings suggest a circular mechanism between children's emotion regulation and ODD symptoms and support the view that emotion regulation, particularly emotion lability/negativity, plays an important role in the development of ODD symptoms. [ABSTRACT FROM AUTHOR]

Craniopharyngioma (CP) is a histologically benign tumor with high mortality and morbidity. Although surgical treatment is essential in managing CP, the best surgical approach is debated. A retrospective cohort of 117 patients with adult-onset CP (AOCP) treated between 2018 and 2020 in Beijing Tiantan Hospital was identified and examined. The effects of traditional craniotomy (TC) and endoscopic endonasal transsphenoidal surgery (EETS) on the extent of surgical resection, hypothalamic involvement (HI), postoperative endocrine function, and postoperative weight were compared in the cohort. The cohort comprised 43 males and 74 females, divided into the TC (n = 59) and EETS (n = 58) groups. The EETS group possessed a higher rate of gross total resection (GTR) (adjusted odds ratio (aOR) = 4.08, p = 0.029) and improved HI (aOR = 2.58, p = 0.041) than the TC group. Worse postoperative HI was only observed in the TC group (5 patients). The EETS was associated with fewer adverse hormonal outcomes, including posterior pituitary dysfunction (aOR = 0.386, p = 0.040) and hypopituitarism (aOR = 0.384, p = 0.031). Additionally, multivariate logistic regression analysis confirmed that EETS was related to fewer cases of weight gain >5% (aOR = 0.376, p = 0.034), significant weight change (aOR = 0.379, p = 0.022), and postoperative obesity (aOR = 0.259, p = 0.032). Compared to TC, EETS shows advantages in accomplishing GTR, hypothalamus protection, postoperative endocrine function reservation, and postoperative weight control. These data suggest that the EETS deserves more application in managing patients with AOCP. [ABSTRACT FROM AUTHOR]

Near-zero carbon emission power (NZCEP) plants, consisting of gas-fired units; wind turbines; power-to-gas (P2G); and carbon capture, utilization and storage (CCUS) systems, have recently received a lot of attention due to their enormous benefits in reducing carbon emissions and increasing the consumption of renewable energy. However, a complex environment of interest and a combination of risks makes their development very slow. This paper establishes a risk analysis framework for NZCEP considering multi-stakeholder participation. Firstly, a synthetic risk factor system was constructed based on stakeholders' interests. Subsequently, interval type II trapezoidal fuzzy numbers were used and final weights were calculated from both subjective and objective aspects. Finally, we applied an acronym in Portuguese of the interactive and multi-criteria decision-making (TODIM) method to site selection to achieve a balance of interests of all stakeholders. In addition, a case study was conducted. The case result demonstrates that Zhengzhou in Henan Province is the best choice for a NZCEP power plant. A further finding is that government plays an important role in the development of NZCEP plants, with site selection results being the most sensitive to changes in the government's risk appetite. Moreover, human resources are an important factor in the siting of an NZCEP plant. [ABSTRACT FROM AUTHOR]

Planning for marriage and childbearing is an important part of many young adults' lives. In this study, we investigated ways in which ideas about family formation among Chinese international students were associated with personal, interpersonal, and cultural factors. In total, 265 childless Chinese international students (Mage = 23 years; all cisgender) in the United States participated in an online survey; 210 self-identified as heterosexual and 55 as sexual minority individuals. Results showed that sexual minority students chose older ideal ages for marriage and parenthood than did heterosexual students. Moreover, sexual minority students were more likely to see the United States and other regions where same-sex marriage is legal as ideal places to live after marriage, but heterosexual students were more likely to describe China as ideal. In reality, however, many students expected to return home to China, and there were no differences in their expectations as a function of sexual identities. In addition, students who reported greater acculturation to culture of the United States were more likely to choose the United States as the ideal place to live. Students who endorsed the importance of filial piety and who perceived more support from family were more likely to view China as the ideal place to live. Finally, sexual minority students who wanted to become parents chose a greater variety of pathways to parenthood than did heterosexual students. Results highlighted the role of sexual orientation, social support, and cultural ideals in shaping the ways Chinese students thought about future families. [ABSTRACT FROM AUTHOR]

In recent years, the microgrid system (MGS) has become an important method for the consumption of renewable energy sources (RES). In the actual operation process, the uncertainties of RES add to the complexity of the MGS operation. Furthermore, the MGS is often operated by multiple subsystem operators. The benefit distribution among subsystem operators is an important factor affecting the overall stable operation of the MGS. In order to resist the interference of the above factors, a two-stage optimization method is proposed in this paper, which includes a bi-level robust optimization (BRO) model in the overall scheduling stage of the MGS and a nucleolus-based cooperative game (NCG) model in the internal cost allocation stage among the subsystem operators. The simulations demonstrated the following outcomes: (1) the P2G device can reduce the operating cost of the MGS by converting electricity into natural gas when the electricity price is low; (2) the two-stage optimization method can ensure the stable operation of the MGS by resisting the disturbance of uncertain wind power outputs in the overall scheduling stage and realizing a reasonable cost allocation among the subsystem operators in the internal cost allocation stage. [ABSTRACT FROM AUTHOR]

Federated learning facilitates collaborative learning among multiple parties while ensuring client privacy. The vulnerability of federated learning to diverse Byzantine attacks stems from the opacity inherent in its local training processes. This issue becomes more pronounced when data among clients lacks independent and identical distribution. Concurrently, the advent of gradient inversion attacks introduces an escalating risk to the confidentiality and integrity of the federated learning system. This work introduces a framework to tackle the difficulties associated with Non-IID data within federated learning. Initially, it classifies diverse data using Euclidean distance to alleviate intra-cluster heterogeneity. A privacy-preserving Byzantine fault tolerance strategy utilizing cosine similarity is implemented within each cluster. We adopt normalizing and introduce historical momentum to the inter-cluster aggregation. The integration of homomorphic encryption ensures that clients' gradient information participates in training under ciphertext, safeguarding against gradient inversion attacks. Lastly, we conduct a comparative analysis against classical and latest algorithms under various conditions. These results validate the effectiveness of our design in enhancing robustness in Non-IID data. [ABSTRACT FROM AUTHOR]

As the largest emitter of carbon dioxide all over the world, China requires a rapid breakthrough and large-scale commercial application of carbon capture, utilization and sequestration (CCUS) technology to achieve the 2060 carbon neutrality target. However, the process of CCUS technology commercialization in China is quite slow. Firstly, an obstacle system with 15 factors is established based on a literature review and expert consultation, namely on economic, technical, political, market, and social obstacles. Secondly, taking into account the uncertainty and randomness inherent in subjective judgment, Vague set is introduced for the first time to improve the DEMATEL-ANP (DANP) method in order to analyze comprehensive importance and causal relationship of obstacles. According to the study, in advancing CCUS's commercialization in China, economic obstacles are simply the tip of the iceberg, with the deeper reasons rooted in political obstacles. Specifically, seven critical obstacles are lack of standards and regulations, inadequate legal and regulatory framework, insufficient incentive policies, limited carbon dioxide conversion efficiency, high energy consumption, low rate of return on investments and low investment enthusiasm of enterprise. We conclude with a series of recommendations to address these obstacles, and these findings can be used as a guide for government regulation and business practice. [ABSTRACT FROM AUTHOR]

To obtain the price return and price volatility spillovers between renewable energy stocks, technology stocks, oil futures and carbon allowances under different investment horizons, this paper employs a frequency-dependent method to study the dynamic connectedness between these assets in four frequency bands. The results show that, first, there is a strong spillover effect between these assets from a system-wide perspective, and it's mainly driven by short-term spillovers. Second, in the time domain, technology stocks have a more significant impact on renewable energy stocks compared to crude oil. However, through the study in the frequency domain, we find renewable energy stocks exhibit a more complex relationship with the other two assets at different time scales. Third, renewable energy stocks have significant spillover effect on carbon prices only in the short term. On longer time scales, other factors such as energy prices, climate and policy may have a greater impact on carbon allowance prices. Fourth, the spillover effect of the system is time-varying and frequency-varying. During the European debt crisis, the international oil price decline and the COVID-19 pandemic, the total spillover index of the system has experienced a substantial increase, mainly driven by medium, medium to long or long term spillovers. [ABSTRACT FROM AUTHOR]

Magnetic field noise is a key factor limiting the resolution of quantum precise measurement. In active magnetic field compensation systems, the large coil constant and fixed noise of the coil and current source, respectively, cause excessive noise. This study proposes a differential biplanar coils (DBCs) design method by comprehensively optimizing two sets of biplanar coils with differential evolution (DE) algorithm, which can reduce the coil constant by two magnitude orders while ensuring high uniformity. The peak-to-peak magnetic field at the center point is reduced to 0.8 pT, and the magnetic field noise is reduced to 8 fT/ Hz , which is a reduction of 94.4%. The low noise active magnetic compensation system based on the differential biplanar coils can improve the accuracy of the magnetic shielding room (MSR) internal magnetic field control and reduce magnetic field noise effectively. The proposed method contributes to generating a near-zero magnetic field environment with low magnetic field noise, which is critical to promoting magnetoencephalography (MEG) measurements. • Comprehensive design and optimization method for biplane coils. • Low noise magnetic field compensation system. • Working environment for the precise MEG measurement. [ABSTRACT FROM AUTHOR]

We investigated parenting aspirations among Chinese international students of diverse sexual identities in the United States. We also studied associations of perceived impact of Chinese and American culture with parenting aspirations. In total, 265 Chinese international students (Mage = 23.03years; all cisgender) participated in an online survey; 210 self-identified as heterosexual (58 male and 152 female) and 55 as members of sexual minorities (16 male and 39 female). Results showed that sexual minority students were less likely than heterosexual students to aspire to become parents. Both for heterosexual and for sexual minority students, the perceived impact of Confucianism was positively associated with parenting aspirations, but that of American culture was negatively associated with parenting desire. Moreover, sexual identity moderated the association between the perceived impact of Buddhism and parenting aspirations. For heterosexual students, the association between perceived impact of Buddhism and parenting aspirations was positive, but for sexual minority students, it was negative. Our findings highlighted the essential role of Confucianism in aspirations for the future among Chinese youth. The impact of Buddhism was, however, moderated by students’ sexual identities. Overall, the results extend those of earlier research on the role of sexual identities in shaping young adults’ aspirations. [ABSTRACT FROM AUTHOR]

In this paper, AlN-YAG: Ce composite phosphor ceramics with high thermal conductivity was prepared by accompanying YAG: Ce phosphor with an AlN matrix. The phosphor ceramics was densified at 1700 °C for 3 h, and YAG: Ce phosphor particles were uniformly dispersed in the AlN matrix without any chemical reaction and impure phases around the contact interfaces. The thermal conductivity of the sample with 10 wt. % YAG: Ce phosphor was as high as 68.8 W m−1 K−1. As a result, the saturation power density is up to 39.6 W mm−2 with a luminous emittance of 1516 lm mm−2, showing excellent resistance to high flux density photon irradiation. This work presents a method to enhance the thermal conductivity of phosphor ceramics for high power laser lighting. [ABSTRACT FROM AUTHOR]

Kirigami, the ancient paper art of cutting, has recently emerged as a new approach to construct metamaterials with novel properties imparted by cuts. However, most studies are limited to thin sheets‐based 2D kirigami metamaterials with specific forms and limited reconfigurability due to planar connection constraints of cut units. Here, 3D modular kirigami is introduced by cutting bulk materials into spatially closed‐loop connected cut cubes to construct a new class of 3D kirigami metamaterials. The module is transformable with multiple degrees of freedom that can transform into versatile distinct daughter building blocks. Their conformable assembly creates a wealth of reconfigurable and disassemblable metamaterials with diverse structures and unique properties, including reconfigurable 1D column‐like materials, 2D lattice‐like metamaterials with phase transition of chirality, as well as 3D frustration‐free multilayered metamaterials with 3D auxetic behaviors and programmable deformation modes. This study largely expands the design space of kirigami metamaterials from 2D to 3D. [ABSTRACT FROM AUTHOR]

Based on the previous observations, uncertain time series analysis provides plausible description for experimental data, and predicts future values by characterized observations and disturbance as uncertain variables under the framework of uncertainty theory. Sometimes, the current observation is simultaneously impacted by the past observations and past disturbance terms. Uncertain autoregressive moving average (UARMA) model emerged as the times require. Due to the inevitable presence of unknown parameters in the model, it is crucial to estimate these unknown parameters robustly based on observed data. Motivated by this, a way to calculate least absolute deviation estimations for unknown parameter in UARMA model is studied by transformation this model into an uncertain autoregressive model. Forecast value and confidence interval for the future value are derived from the fitted model. Finally, two real data analyses with imprecise and precise observations of carbon dioxide emissions are given to show the effectiveness of our proposed method, and uncertain hypothesis is documented to test our model. Besides, it also explains why stochastic time series model is not applicable for this case. [ABSTRACT FROM AUTHOR]

Micro-tubular protonic ceramic fuel cells (MT-PCFCs) are prominently advantageous in energy conversion and storage, such as intermediate operating temperature, large volumetric power density, and low sealing requirements. Formation of thin and dense electrolyte film and efficient current collection, particularly from the micro lumen, are the primary challenges for preparing high-performance MT-PCFCs. The present work carries out a one-step fabrication of triple-layer hollow fibers (TLHFs) with anodic current collector/graded anode/electrolyte using BaCe 0 · 7 Zr 0 · 1 Y 0 · 2 O 3-δ via the phase-inversion based co-spinning/co-sintering technique. A BaCo 0 · 4 Fe 0 · 4 Zr 0 · 1 Y 0 · 1 O 3-δ based porous cathode is then applied on the TLHF's outer surface to create a complete fuel cell. The resultant single MT-PCFC yields a peak power density of 601.2 mW cm−2 at 700 °C. Furthermore, an MT-PCFC stack is made by bundling seven TLHFs using the porous cathode. With an effective area exceeding 12 cm2, the MT-PCFC stack generates a power output of 2.5 W at 700 °C. The stability test lasts for 100 h at 600 °C under 100 mA cm−2 and for next 60 h at varied temperatures from 700 to 600 °C under 200 mA cm−2. The inventive design of TLHFs facilitates the scale-up of fuel cells, promoting the development of a large-scale MT-PCFC stack or systems. [Display omitted] • Anodic collector/anode/electrolyte TLHFs were batch-fabricated in single-step. • The single MT-PCFC offered an MPD of 601.2 mW/cm2 at 700 °C. • A 12 cm2 MT-PCFC stack was assembled by bundling 7 TLHFs using a porous cathode. • The MT-PCFC stack provided power output of 2.5 W at 700 °C. • The stack offered stable outputs for 160 h at varied temperatures from 600 to 700 °C. [ABSTRACT FROM AUTHOR]

Fe0 and Ni0 nanoparticles (NPs) of certain size were synthesized and added to the hydrogen production system from cotton stalk hydrolysate using Klebsiella sp. WL1316. Fe0 and Ni0 NPs with a size of 50 nm at all concentrations effectively improve hydrogen production during mid to late fermentation stages; particularly, the highest daily hydrogen production obtained following treatment with 50 nm Fe0 NPs at 30 mg/L fermented for 96 h significantly increased by 61% comparing to the control treatment. The reducing sugar consumption in cotton stalk hydrolysate and ΔOD 600 could be improved to some extent by Fe0 and Ni0 NPs supplementation. Addition of Fe0 or Ni0 NPs of 50 nm at a concentration of 30 mg/L resulted in enhanced cumulative hydrogen production with improvement of hydrogen yield reached higher than 20%, and the values of Y(H 2 /S) were all higher than 90 mL/g substrate , reflecting good hydrogen production and substrate consumption. The analysis of the main soluble metabolites profile revealed that supplementation with Fe0 and Ni0 NPs of suitable size and concentration may decrease the metabolic flux in the competitive branch of hydrogen production and increase the metabolic flux of the key node that leads to hydrogen generation, thus promoting biohydrogen synthesis. • Fe0 and Ni0 NPs with suitable size and concentration enhanced hydrogen production. • Suitable Fe0 and Ni0 NPs addition improved sugar consumption and bacterial growth. • Emphasize NP size effect on enhancement of hydrogen production for the first time. • Daily hydrogen production increased by 61% upon optimum Fe0 NPs addition at 96 h. • Hydrogen yield enhanced higher than 20% upon optimum Fe0 and Ni0 NPs addition. [ABSTRACT FROM AUTHOR]

We examined the influence of assessors' professional power and social connections on their decision making regarding evaluation for funding of new business projects, as well as the moderating effect of the assessors' own job security. Using 1,517 observations from 2017 Beijing Innofund data, we found that the assessors' professional power and social connections were both positively related to their evaluation scores. The job security of the assessors significantly positively moderated the effect of their social connections, but the moderating effect of job security on their professional power was nonsignificant. Theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

With the great concerns on alleviating the environment pollution and traffic congestions, there is a trend for developing light electrical vehicles in urban areas. This paper proposes an outer rotor flux switching permanent magnet machine (FSPMM) for light electric vehicle drive systems. The topology, operational principle and performance of the proposed machine are introduced. Then the procedure for choosing suitable combinations of stator slots and rotor poles is presented by using the sizing equation and finite element method (FEM). It is found that the optimal combination is 6 stator slots and 19 rotor poles for this application. Finally, a 188 W 120 rpm outer rotor FSPMM of the optimal stator/rotor combination is designed and analyzed. The magnetic field distribution and machine parameters are calculated by using FEM, and the performance is predicted based on the current vector control strategy. [ABSTRACT FROM AUTHOR]

Higher-order masking schemes have been proven in theory to be secure countermeasures against side-channel attacks in the algorithm level. The ISW framework is one of the most acceptable secure models of the existing higher-order masking schemes. However, a gap may exist between scheme and implementation. Several analyses have exhibited the weakness of masking in hardware designs on FPGAs. Firstly, we give the definition of leakage point and introduce three implementation logical flaws: glitch, EDA optimization and intermediate variable of scheme flaw. Secondly, we propose a leakage verification flow for implementing and verifying circuits realized higher-order masking schemes to avoid these leakage points. The flow provides an efficient evaluation method to locate and identify leakage points in masking hardware implementations. With the knowledge of the weaknesses of implementation, the implementation should be modified by corresponding methods to fix flaws, especially for glitch, which has been regarded as the main challenge of masking in hardware designs, we provide a method to remove the leakage point using Dijkstra algorithm with no extra time and area overheads. Finally, the design flow is evaluated on the implementation of Rivain&Prouff masking. Our experiments demonstrate how it automatically locates and protects the implementation. In addition, the experiments are also performed on flawed implementations due to EDA optimization and intermediate variables. • We analyze the practical security of implementations of masking schemes, which have been proved secure in theory. • We give the definition of leakage point and classify the implementation flaws of masking into three types. • An efficient evaluation method is proposed to locate and identify leakage points in hardware implementations. • We provide an automatically security verification flow and several suggestions to remove the leakage points. • A secure design flow is provided for implementing and verifying circuits realized higher-order masking schemes. [ABSTRACT FROM AUTHOR]

Due to the fragile nature but the irreplaceable role of proteins as analytical tools, the preservation of proteins to minimize their activity and functionality loss is an essential issue for analytical applications. The hybridization of proteins and nanomaterials (protein-nanomaterial hybrids, PN hybrids) integrates diversified merits of proteins and nanomaterials and even shows synergy effects, has paved a new way of significant prospects of protein preservation for storage and operation in a long time and under extreme un-biocompatible environment. Especially, recent years have witnessed the flourish of novel strategies of protein preservation based on PN hybrids consisting of emerging nanomaterials, including metallic nanomaterials, graphene and analogs, and porous frameworks (metal-organic frameworks and covalent organic frameworks). This review covers the fabrication strategies and protein preservation application of new PN hybrids (mainly in past four years). The integration and synergy between proteins and nanomaterials for protein preservation are emphatically summarized and discussed. • New strategies for the fabrication of the hybrids of protein and emerging nanomaterials. • New trend in protein preservation application of protein-nanomaterial hybrids. • Integration and synergy between protein and nanomaterials in hybrids are discussed. • Current challenges for the fabrication and application are discussed. [ABSTRACT FROM AUTHOR]

Flexoelectricity is an electromechanical coupling between polarization and strain gradient, which not only exhibits strong size dependency but is structure associated (geometry or microstructure). By the definition of flexoelectric coefficients, the flexoelectricity-related strain gradients can be generated by tailoring mechanical structures, such as the traditional designed truncated pyramid. In this work, a novel asymmetric nanocylinder is composed of functionally graded materials presented with uniform pressures on the top surface to create a relatively large inhomogeneous strain field for the achievement of obvious flexoelectric polarization. Based on the power-law-distributed material property assumption, we investigate the flexoelectricity of the proposed functionally graded nanocylinder. Based on the extended linear theory of piezoelectricity, the closed-form solutions are obtained, which can specifically characterize the size-dependent flexoelectricity. The most common setups are applied to quantify the flexoelectric response. From the numerical results, we can conclude that the electromechanical properties can be significantly influenced by the given FG configuration with graded material parameters, which can be a guideline for the design of novel flexoelectric devices. [ABSTRACT FROM AUTHOR]

Micro-tubular protonic ceramic fuel cells (MT-PCFCs) offer significant advantages in energy utilization and storage, including high stability/durability and intermediate working temperature. Inefficient intraluminal current collection and costly fabrication processes are challenges for high-performance MT-PCFCs. Herein, hierarchically structured Ni/Ni–BaCe 0.7 Zr 0.1 Y 0.2 O 3-δ dual-layer hollow fibers (DLHFs) have been fabricated by the phase-inversion assisted co-spinning/co-sintering technique. By adjusting the viscosity of anode suspension, the DLHFs' microstructure is tailored and optimized for porosity, pore size, and thickness of collector layer and spongy region. After assembling MT-PCFCs, effects of DLHFs' microstructure on fuel cell performance are investigated, revealing that a thinner spongy region reduces gas transfer resistance, lowers polarization impedance, and enhances fuel cell performance. A maximum power density of 687.1 mWcm−2 for the optimum MT-PCFC is reached at 700 °C. The innovative DLHF design enhances current collecting efficiency for MT-PCFCs and exhibits potential in other micro-tubular applications, such as hydrogen pumps and electrochemical reactors. [Display omitted] • Hierarchical structure anodic collector/anode DLHFs were fabricated in single-step. • A mesh-like current collector is integrated inside the anode microtubule. • Adjusting PVP content altered the porosity, pore size, and morphology of the DLHFs. • Thinner spongy region reduced polarization impedance and enhanced cell performance. • MT-PCFC with 0.7 wt% PVP content offered an MPD of 687.1 mW/cm2 at 700 °C. [ABSTRACT FROM AUTHOR]

With global warming, extreme weather frequently and severely appears globally. Extreme precipitation is one of the extreme weather events that can cause many natural disasters, such as floods and waterlogging. In this study, Global Precipitation Climatology Project (GPCP) daily precipitation data were used to investigate extreme precipitation and its contribution to annual precipitation in different global climate regions and typical river basins. The climate types included equatorial climates (EC), arid climates (AC), warm temperate climates (WTC), snowy climates (SC) and polar climates (PC). R99p, Rx5day, CWD and R20 was selected as extreme precipitation indices in this study; extreme precipitation days were defined by CWD and R20. The results showed that EC and WTC had higher extreme precipitation level; SC and PC had lower extreme precipitation amounts and days than AC. R99p, Rx5day and CWD monitored higher extreme precipitation contribution degrees in AC; however, R20 monitored higher contribution degrees in EC and WTC. R99p, Rx5day and CWD showed higher extreme precipitation contribution degrees in North Africa, the Middle East, Australia and northwestern China; R20 showed higher contribution degrees in South America, the southeastern United States and South Asia. Based on historical observational data, Heilongjiang Basin (HB), Yellow River Basin (YERB), Yangtze River Basin (YARB), Ganges River Basin (GRB), Danube River Basin (DRB) and Mekong River Basin (MERB) had high-frequency extreme precipitation in summer. The research results are helpful for understanding the characteristics of extreme precipitation and provide a reference for flood control and disaster reduction in different climatic regions and main river basins. [ABSTRACT FROM AUTHOR]

To accommodate the increased demand for electric vehicle(EV) charging in China, this paper examines electric vehicle charging station(EVCS) location strategies from the perspective of private investors, taking full account of the competitive environment of existing EVCSs in the region. First of all, a three-level location model considering dynamic pricing is developed, which includes user decisions, EVCS pricing, and EVCS location decisions. Then, the soft actor-critic(SAC) reinforcement learning algorithm is used to train the optimal pricing strategy for EVCS to guarantee the maximum cumulative revenue. The proposed methodology is verified through case studies based on an industrial park in China. The results show that the proposed methodology can make more economical and scientific location decisions than the traditional method. The dynamic pricing method based on reinforcement learning can provide a reference for the location and operation of more EVCSs. • A dynamic pricing mechanism for EV charging station is constructed. • The location decision of EV charging station is studied from the perspective of investors. • A three-layer model of EV charging station investment is formulated. • User decision, charging price and location of EV charging station are considered. • SAC reinforcement learning algorithm is used to solve the real-time pricing decision of EV charging stations. [ABSTRACT FROM AUTHOR]

Federated Learning (FL) breaks the "data island" and lets clients cooperate in training a shared model with private data locally. And hierarchical framework is used in FL to alleviate the problem of excessive communication overhead. FL provides a certain degree of privacy, but privacy inference and Byzantine attacks still affect the existing FL methods. Moreover, the parameter server brings new security troubles, and the group size limits the model's robustness. Thus, this paper presents a new decentralized FL framework called Trustiness-based Hierarchical Decentralized Federated Learning (TH-DFL) via a Security Robust Aggregation (SRA) rule, which introduces a trust mechanism. This study provides privacy protection and robustness even if there are malicious nodes. Besides, it somewhat reduces communication overhead. A series of comparative studies are also implemented to evaluate the performance of the model. In this process, the Gaussian, the bit-flipping, and other attacks are launched in the simulated federated learning. The results show that on the basis of ensuring privacy and robustness, TH-DFL seeks a better balance between privacy and robustness when the size of the group changes. [ABSTRACT FROM AUTHOR]

Under the carbon peak and neutrality targets, the power generation industry in China is facing an urgent demand for a low carbon transition and participation in the electricity-carbon market. This paper novelty proposes a near-zero carbon emission power plant (NZCEP) integrating gas turbines, wind turbines, power-to-gas and the carbon capture, utilization and storage system. And a two-stage Data-driven Set based robust optimization (DSRO) model, including a day-ahead dispatching phase and a real-time adjustment phase, is conducted to ensure the consumption of renewable energy resources and to develop the optimal operating strategy for NZCEP participation under the electricity-carbon market. The results demonstrated the following outcomes: (1) NZCEP shows better environmental benefits by reducing carbon emissions and consuming renewable energy resources. (2) the DSRO model can resist the interference of wind power output uncertainties and address the issue of traditional robust models being overly conservative. (3) under the electricity-carbon market, NZCEP shows better economic benefits, which can generate additional revenue from selling surplus carbon emission allowances (CEA). Moreover, when the annual average CEA price reaches 355 CNY/t, the NZCEP will achieve full capital cost recovery. • Optimal operation of near-zero carbon emission power plant (NZCEP) is studied. • A Data-driven robust optimization model is proposed for NZCEP operating. • Carbon emissions reduction and wind power accommodation of NZCEP are verified. • The economy of NZCEP participation in the electricity-carbon market is analyzed. [ABSTRACT FROM AUTHOR]

A 40 MHz–4.41 GHz fractional-N frequency synthesizer (FS) with varactor-reconstruction VCO (VRVCO) fabricated in the standard 0.18-μm CMOS process is demonstrated. In the conventional VCO, owing to non-linearity of varactor and parasitic effects of switched-MOSFET, the top and bottom of the tuning curves show nonlinearity. The novel design of VRVCO for tuning sensitivity base on series-shunt hybrid capacitor-varactor part and optimized switched-capacitor bank is incorporated into the 4.41 GHz FS design to reduce the variation of the VCO gain, realize high linearity tuning curves and improve phase noise performance. Furthermore, a noise reduction topology is adopted to decrease phase noise of VRVCO. Simulated results show the proposed VRVCO can improve linearity of tuning frequency over the entire tuning range. The measured results show the overall tuning range exceeds 115% from 1.92 to 4.41 GHz including three VRVCOs with high linearity (fine-tuning sensitivity: 131%, coarse-tuning sensitivity: 106%) and the phase noise is −120dBc/Hz at 1 MHz offset from the carrier frequency of 4.41 GHz. [ABSTRACT FROM AUTHOR]

Under bending deformation, size-dependent and structure-associated strain gradients can occur at the interface of a flexoelectric semiconductor (FS) PN heterojunction. Consequentially, a giant flexoelectric coupling will be induced to significantly enhance the flexoelectric effect of FS structures. To better understand the strain gradient–enhanced modulation performance and also reveal some other new phenomena, in this work, we theoretically and numerically study a beam shaped FS laminated composite subjected to pure bending loads. We first establish a one-dimensional theoretical model and then numerically explore the mechanical behaviors of the selected FS beam laminate. During analysis, structural symmetry breaking and size effect are considered by tuning the beam structural size and material parameters. We find that different from piezoelectric semiconductors whose mobile charges are driven by the piezo-potential, the mobile charges of FS composites induced by the flexo-potential are deterministically associated with strain gradients. Moreover, the strain gradients can exhibit a strong size-dependent effect and are quite sensitive to structural asymmetry and material parameters. We believe that our work can provide a new way to tune the carrier transport and electromechanical characteristics of a PN junction and thus can be useful to guide the next-generation flexotronic device designs. [ABSTRACT FROM AUTHOR]

• Efficient estimation methods for the particle size distribution (PSD) in ferrofluids. • The methods are robust to the measurement errors. • The estimation is based on the magnetization data, instead of TEM data. • Nonlinear programming method is efficient for the estimation of PSD parameters. • Improved Bayesian method is robust to reconstruct the PSD curves of ferrofluids. For the fundamental research and industrial application of ferrofluids, the particle size distribution (PSD) of magnetic nanoparticles is crucial to characterize their material properties. This work aims to develop efficient and robust PSD estimation methods for ferrofluids without interacting particles under two cases, known and unknown distribution types. The main task of the first case is to estimate the distribution parameters for a given PSD. For this purpose, L p norm method is employed to convert the PSD estimation matrix equation into a constrained nonlinear programming problem. Then the nonlinear programming method (NPM) is presented to estimate the PSD parameters based on the magnetization data. The main tasks of the second case are to reconstruct the PSD curve and estimate the distribution type and parameters. To achieve these goals, an improved Bayesian method is proposed by using the estimation obtained from NPM as its prior information. Then a non-parameter hypothesis test method, Shapiro-Wilk test is introduced to determine the distribution type of the PSD. To illustrate the effectiveness of the proposed methods, theoretical analysis and Monte Carlo simulation are conducted based on the material parameters and experimental results of two ferrofluid samples. Through the comparison, it is found that the NPM is less sensitive to the noise like measurement errors and it can provide more accurate estimations than conventional inversion methods. Moreover, the proposed improved Bayesian method is efficient and robust to the noise, which can be used to reconstruct the PSD curves of ferrofluids without using the conventional time-consuming experimental methods like transmission electron microscopy. [ABSTRACT FROM AUTHOR]

The surface molecular imprinting technique is to polymerize and establish the molecular recognition site on the outer layer or surface of the carrier. As a result, the surface molecularly imprinted polymers have the advantages of fast binding speed, strong identification selectivity, high binding capacity and improved efficiency of imprinted materials. In this paper, the principle of surface molecularly imprinted polymers and four preparation methods (sol-gel method, graft copolymerization method, sacrificial carrier method, polymerization plus membrane method, active controllable free radical polymerization) were briefly introduced. Four aspects of drug separation and analysis (traditional Chinese medicine extraction and separation; drug sensors; chiral drug resolution; the application) in drug release was reviewed. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical responses of a thick-walled functionally graded hollow cylinder subject to a uniform magnetic field and inner-pressurized loads are studied. Rather than directly assume the material constants as some specific function forms displayed in pre-studies, we firstly give the volume fractions of different constituents of the functionally graded material (FGM) cylinder and then determine the expressions of the material constants. With the use of the Voigt method, the corresponding analytical solutions of displacements in the radial direction, the strain and stress components, and the perturbation magnetic field vector are derived. In the numerical part, the effects of the volume fraction on the displacement, strain and stress components, and the magnetic perturbation field vector are investigated. Moreover, by some appropriate choices of the material constants, we find that the obtained results in this paper can reduce to some special cases given in the previous studies. [ABSTRACT FROM AUTHOR]

Large-scale wind farms are usually integrated into the transmission system. Applying traditional steady-state power-frequency based protection strategies in these transmission lines creates challenges such as: (1) the fault current of the wind farm might be dominated by non-power-frequency components caused by the activation of their own protection systems during fault ride through (FRT). The frequency of the dominant component is determined by the rotor speed at the fault inception and might vary from 0.7 to 1.3 times the power frequency. This will create errors in phasors calculated at the power-frequency. (2) The steady-state fault current angles of wind farms are fully controlled by their power converters. The variety of control actions of the different converters during FRT makes these phase angles greatly deviate from those of the synchronous generators. Protection systems that use double-ended phasors such as current differential schemes will suffer from low sensitivity or even malfunction when large-scale wind farms are integrated. Therefore, a novel full-time transient current waveform similarity based protection scheme is proposed to deal with these issues. The full-time current protection scheme uses both the power-frequency and non-power-frequency characteristics and can therefore reduce the influence of power-frequency phasor calculation errors to a minimum. The proposed method uses the transient current (within 10 ms after the fault inception) and is ignores the features of the steady-state fault current. In other words, the proposed protection is suitable for wind farms with a variety of controls. In the proposed method, the correlation coefficient index is used to calculate the similarity of the transient current signals at both ends of the line. Both experimental and field testing results show that using a common sampling frequency, the proposed protection scheme only uses current information and can correctly identify all types of external and internal line faults in a short period of time and can offer better performance for high fault resistance and noise, both for different types of wind farms. All these features and contributions make the new protection feasible for industry application. [ABSTRACT FROM AUTHOR]

• Macro tooth flank modeling, discretization and discrete point interpolation. • Determination of autocorrelation function from the actual measurement. • Fast Fourier transformation (FFT) based micro flank topography reconstruction. • Comprehensive effect considering both macro and micro flank. • Micro flank geometric topography reconstruction for spiral bevel and hypoid gears. Focusing on comprehensive effect of both macro and micro geometries, accurate flank geometric topography design in a micro scale is developed for spiral bevel and hypoid gears showing a complex flexural behaviors. Firstly, macro flank modeling is performed for determining sparse tooth surface by using the discrete point interpolation. For micro-scale and smooth flank points, the vector between the current point and the adjacent tooth surface point are used as the tangent vector, and the vector in normal direction is obtained by calculating vector product of tangent vector. Then, fast Fourier transform (FFT) method is employed for the micro flank geometric topography reconstruction considering comprehensive effect. While determining the height distribution parameters from the actual measurement, autocorrelation function (ACF) is established to obtain the reconstructed roughness height matrix, and these microscopic height data are added to the corresponding macroscopic smooth tooth surface points in the normal direction for accurate micro flank geometric topography generation. The proposed method is exercised with an example double helical grinding spiral bevel gear from an aerospace application to demonstrate the impact of reconstruction design on flank performance. [ABSTRACT FROM AUTHOR]

Hydrogen fuel cell vehicles (HFCVs), as an important strategic path for global sustainable development and energy transition, have now become an important support for the global energy and transportation sectors. The United Kingdom, Japan, the United States, China, and other countries are vigorously developing HFCVs and increasing the construction of hydrogen stations. Before HFCVs enter the stage of rapid commercialization and development, it is necessary to investigate the factors that influence consumer HFCV adoption. In this paper, meta-analysis used 24 pieces of literature to include in a systematic evaluation of the existing research on the factors that influence consumer willingness to purchase HFCVs, setting influencing factors as the dependent variable, to clarify the specific roles of different influencing factors and to address the problem of mixed and contradictory findings in the literature. The results of the study show that: (1) The influence of gender and age on consumer willingness to purchase HFCVs cannot be judged. (2) Education, individual income, household income, family car number, driving range, knowledge, fuel availability, hydrogen refueling station density, environmental impact, policy incentives and attitudes all have a positive effect on HFCV adoption. (3) Household size, purchase price, fuel cost, maintenance cost and refueling time have a negative effect on HFCV adoption. (4) The purchase price, knowledge, fueling time, hydrogen refueling station density, and policy incentives significantly influence HFCV adoption. This paper provides new research methods and perspectives for the HFCV field and presents theoretical references for future governmental promotion of HFCV. • Meta-analysis of 24 studies conducted for consumers' intention to purchase HFCVs. • Subgroup analysis provides evidence of heterogeneity among estimates. • Household size and the other 4 influencing factors inhibit HFCV adoption. • Education and the other 9 influencing factors promote HFCV adoption. • The purchase price and other 4 influencing factors significantly influence HFCV adoption. [ABSTRACT FROM AUTHOR]

Photodegradation is the main depletion pathway for methylmercury (MeHg) in surface water. The formation of MeHg-dissolved organic matter (DOM) complexes has been found to be a key step in MeHg photodegradation. However, the major functional groups involved in the DOM-mediated process have yet to be clearly resolved. In this work, we systematically investigated the effects of DOM molecular structures on MeHg photodegradation by using a variety of organic ligands with different functional groups (e.g., thiosalicylate, thiophenol, and thioaniline). The results showed that thiol and phenyl groups may be the major functional groups governing DOM-mediated MeHg photodegradation, with photodegradation rates also dependent on the type (carboxyl, hydroxyl, and amino group) and position (ortho-, meta-, and para-) of other chemical substituents. The addition of “non-photochemically active” thiol ligands (e.g., mercaptoethanol and dithiothreitol) and high concentrations of Cl − can significantly inhibit the o-thiosalicylate-induced MeHg photodegradation, indicating that complexation of MeHg with these ligands is necessary for MeHg photodegradation. Sparging with O 2 had a negligible effect on MeHg photodegradation, while sparging with N 2 significantly enhanced MeHg photodegradation. This finding suggests that MeHg photodegradation may be a reductive process, which was further supported by identification of the degradation products of MeHg. A possible protonolysis mechanism of MeHg photodegradation in the presence of o-thiosalicylate was then proposed based on the findings of this study. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is among the most concerned contaminants in the world. It has three major chemical forms in the environment, including Hg 0 , Hg 2 + , and methylmercury (MeHg). Due to their differences in toxicity, mobility, and bioavailability, speciation analysis is critical for understanding Hg cycling and fate in the environment. SnCl 2 reduction-atomic fluorescence spectrometry detection is the most commonly used method for analyzing inorganic Hg. However, it should be noted that MeHg may also be reduced by SnCl 2 , which would result in the overestimation of inorganic Hg. In this study, the reduction of MeHg by SnCl 2 in both de-ionized (DI) water and four natural waters was investigated. The results showed that MeHg could be reduced by SnCl 2 in DI water whereas this reaction was hard to occur in tested natural waters. By investigating the effects of water chemical characteristics (dissolved organic matter, pH and common anions and cations) on this reaction, SO 4 2 − was identified to be the dominant factor prohibiting SnCl 2 induced MeHg reduction in natural waters. SO 4 2 − in natural waters was evidenced to be reduced to S 2 − by SnCl 2 and the generated S 2 − can complex with MeHg to form MeHgS − which is hard to be reduced by SnCl 2 . Findings of this study indicate that the effect of MeHg reduction by SnCl 2 on inorganic Hg analysis is negligible in natural waters; however, at simulated experimental systems without SO 4 2 − , SO 4 2 − should be added as protecting agents to prevent MeHg reduction when analyzing inorganic Hg if it would not cause any other unwanted effects. [ABSTRACT FROM AUTHOR]

The surface imprinted material of one single enantiomer of ibuprofen ((S)-ibuprofen) was successfully prepared using the novel surface imprinting technique of synchronously graft/crosslinking-polymerizing and molecule imprinting. Micron sized-silica gel particles as matrix were first modified with coupling agent γ-mercaptopropyl trimethoxysilane (MPMS), obtaining MPMS-SiO2 particles, on which there was a great deal of mercapto group (‒SH). Hydroxyethyl methylacrylate (HEMA) as functional monomer and dibenzoyl peroxide (BPO) as initiator were dissolved into 1,2-dichloroethane (DCE), and HEMA molecules are automatically combined around (S)-ibuprofen molecules by right of multi-site hydrogen bonds, forming self-assembly complex. A surface-initiating system of ‒SH/BPO was constituted at the interface between MPMS-SiO2 particles and DCE solution. The free radicals produced on the surfaces of MPMS-SiO2 particles initiated HEMA molecules around (S)-ibuprofen molecules to produce graft/crosslinking-polymerization on the surfaces of SiO2 particles. At the same time, (S)-ibuprofen molecules were wrapped in the cross-linked networks so that the surface-imprinting of (S)-ibuprofen was realized, forming (S)-ibuprofen surface imprinted particles ((S)-IBU-SIP). The enantiomeric recognition and resolution properties of (S)-IBU-SIP particles were investigated. The experimental results show that (S)-IBU-SIP particles have excellent enantiodiscrimination property and enantioseparation ability. The binding capacity of (S)-IBU-SIP particles for (S)-ibuprofen gets up to 177 mg g−1, and the selectivity coefficient of (S)-IBU-SIP particles for (S)-ibuprofen relative to (R)-ibuprofen is 5.03. For the ibuprofen raceme solution, after solid phase extraction by (S)-IBU-SIP particles, the optical purity (ee value of (S)-ibuprofen) of the eluent reaches up to 82.5%, whereas the optical purity (ee value of (R)-ibuprofen) of the supernatant is 44.2%. [ABSTRACT FROM AUTHOR]

An efficient acousto-optic Q-switched laser operation of Yb:(Lu x Gd 1-x ) 3 Ga 5 O 12 (x = 0.062) (Yb:LGGG) crystal is demonstrated, producing stable pulses with repetition rate ranging from 1 to 20 kHz. Under the absorbed pump power of 8.75 W, the maximum average output power of 3.26 W is obtained at the pulse repletion rate of 1 kHz, corresponding to the slope efficiency as high as 52%. The pulse width of 14.5 ns is achieved with the pulse energy and peak power of 3.26 mJ and 225 kW, respectively. It indicates great potential of Yb:LGGG crystal for generating pulsed lasers. [ABSTRACT FROM AUTHOR]

A new hydrogen-producing bacterium was isolated from the intestine of wild carp (Cyprinus carpio L.) of the Tarim River Basin. The isolate was identified as Klebsiella sp. based on 16S rDNA gene sequencing and examination of physiological and biochemical characteristics. The isolated strain, Klebsiella sp. WL1316, could effectively produce a high yield of hydrogen by using cotton stalk hydrolysate as substrate. The optimum fermentation conditions for hydrogen production were determined as follows: an initial sugar concentration of 40 g/L, a fermentation temperature of 37 °C and an initial pH value of 8.0. The scaled-up fermentation process was conducted in a 5-L fermenter using these parameters. Higher productivities with maximum daily hydrogen production of 937.0 ± 41.0 mL L−1 day−1, cumulative hydrogen production of 2908.5 ± 47.4 mL L−1, viable cell count of (20.2 ± 0.6) × 108 CFU mL−1 and hydrogen yield of 1.44 ± 0.08 mol mol−1sugarconsumed were obtained. The cumulative hydrogen production was predicted by the modified Gompertz equation with R2 of 0.997, and values of Rm and P were 44.8 mL L−1 h−1 and 3057.6 mL L−1, respectively. These results indicated that the strain Klebsiella sp. WL1316 resulted in a high hydrogen production rate (HPR) and good hydrogen production potential. Moreover, this strain exhibited higher values of maximum hydrogen yield and HPR than the reported pure cultures. [ABSTRACT FROM AUTHOR]

An advanced surface imprinting technique, i.e., the technique of synchronously graft/crosslinking polymerizing of monomer and imprinting of template on the surface of membrane, was designed and used, and a kind of graft-type molecularly imprinted membranes of the single enantiomer of amino acids was successfully prepared. The microfiltration membrane of chloromethylated polysulfone (CMPSF) was used as substrate membrane, and then the aminated polysulfone (AMPSF) membrane was obtained by amination modification. Whereupon, a surface-initiating system of -NH2/ was formed at the interface between AMPSF membrane and an aqueous solution, in which all of the functional monomer dimethylaminoethyl methacrylate (DMAEMA), the crosslinking agent N,N′-methylenebisacrylamide (MBA), initiator (NH4)2S2O8, and L-aspartic acid (L-Asp) as template were dissolved. In the aqueous solution, DMAEMA molecules automatically combined around L-Asp molecules by right of the mutual strong interactions, electrostatic interaction and hydrogen bonding. By initiating of the radicals produced on the surface of AMPSF membrane, the graft/crosslinking polymerization of DMAEMA and MBA took place, and at the same time, L-Asp molecules were embedded into the crosslinked networks. In this way, the grafting-type L-Asp-molecularly imprinted membrane (L-Asp-MIM) was formed. The experimental results show that L-Asp-MIM has high flux and strong mechanical strength like CMPSF microfiltration membrane, and more importantly, it possesses fine chiral recognition selectivity and excellent enantioseparation ability. The selectivity coefficient of L-Asp-MIM for L-Asp reaches 7.52 relative to D-Asp. In the permeation experiment of a raceme solution of Asp, the combination of “gate effect” and “barrier effect” makes the raceme solution of Asp to be well separated, and the optical purity (ee value) of the penetrating fluid gets up to 82%. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a global pollutant of public concern because of its high toxicity and capability for worldwide distribution via long-range atmospheric transportation. Wet atmospheric deposition is an important source of Hg in both terrestrial and aquatic environments. Concentrations of various Hg species in precipitation were monitored from March 2016 to February 2017 in a coastal urban area of Qingdao, and their wet deposition fluxes were estimated. The results showed that the volume-weighted mean (VWM) concentrations of total mercury (THg), reactive mercury (RHg), dissolved THg (DTHg), particulate THg (PTHg), total methylmercury (TMeHg), and dissolved and particulate MeHg (DMeHg and PMeHg) in Qingdao's precipitation were 13.6, 1.5, 5.4, 8.2, 0.38, 0.15, and 0.22 ng L −1 , respectively, and their annual deposition fluxes were estimated to be 5703.0 (THg), 666.6 (RHg), 2304.0 (DTHg), 3470.4 (PTHg), 161.6 (TMeHg), 64.0 (DMeHg), and 95.7 (PMeHg) ng m −2 y −1 , respectively. A relatively high proportion of MeHg in THg was observed in precipitation (3.0 ± 2.6%) possibly due to higher methylation and contributions from an oceanic source to MeHg in the precipitation. Obvious seasonal variations in Hg concentrations and deposition fluxes were observed in the precipitation in Qingdao. Correlation analyses and multiple regression analyses showed that SO 2 , pH, and NO 3 − were the controlling factors for THg in precipitation, whereas the MeHg concentration was primarily controlled by the SO 2 , WS, Cl − , and THg concentrations. PM2.5 and Cl − were the major controlling factors for PMeHg/TMeHg, whereas the TMeHg/THg ratio was mainly influenced by Cl − . The THg and MeHg fluxes were primarily controlled by precipitation, whereas Cl − was also an important factor for the MeHg wet deposition flux. The results of a 72-h backward trajectory analysis in the study region with the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicated that Hg deposition in Qingdao mainly originated from four major sources, i.e., the local area, northwestern China, southeastern China and an oceanic source. This oceanic source is an important source of Hg (especially MeHg) in the precipitation in Qingdao. [ABSTRACT FROM AUTHOR]

Purpose/aim of the study: Our objective was to determine the risk of a subsequent malignancy in patients with glioblastoma multiforme (GBM). Materials and methods: Data of patients with a primary diagnosis of GBM were extracted from the Surveillance, Epidemiology, and End Results database. Patients were divided into three age groups: pediatric, ≤19 years of age; adult, 20-59 years; elderly, ≥60 years. Outcomes were overall survival and incidence of second cancer. Results: A total of 24 348 patients with primary GBM were identified during the period from 2004 to 2013: 349 pediatric, 9841 adults and 14 518 elderly. There were significant differences in terms of sex, race, registry site, tumor histological type, tumor size and extension among the groups. The median survival time for pediatric, adult and elderly patients was 15, 15 and 5 months, respectively. Of the study population, 1.8% developed a second malignancy and the rates of the three groups were statistically different. Secondary tumors of the cranial nerves and other nervous system were the most common occurrence in the adults and elderly. Female, registry site, giant cell glioblastoma, undergoing surgery or radiation therapy were associated with developing a second malignancy. Conclusions: The risk of a second malignancy in GBM patients is 1.8%, and associated with certain patient and treatment factors. [ABSTRACT FROM AUTHOR]