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The development of the carbon market is a strategic approach to promoting carbon emission restrictions and the growth of renewable energy. As the development of new hybrid power generation systems (HPGS) integrating wind, solar, and energy storage progresses, a significant challenge arises: how to incorporate the electricity‐carbon market mechanism into the planning of power system capacity. To address this challenge, this article proposes a coupled electricity‐carbon market and wind‐solar‐storage complementary hybrid power generation system model, aiming to maximize energy complementarity benefits and economic efficiency. The model employs a bi‐level optimization method based on the Improved Coati Optimization Algorithm (ICOA) to optimize the system's capacity planning. Simulations reveal that under the coupled electricity‐carbon market scenario, renewable energy capacity increases by 23% over a 5‐year planning period. Additionally, in this scenario, the total cost is 0.042% lower compared to the scenario without coupling. Under the constraint of a 30% renewable energy penetration rate, the capacity development of wind, solar, and storage surpasses thermal power, while demonstrating favourable total cost performance and the comprehensive complementarity index for HPGS. This model offers decision‐making support for optimizing energy resource allocation and improving system reliability and economic viability. [ABSTRACT FROM AUTHOR]

Water structures take an important role in chemical and biological systems, because the structure and function of a molecule may depend on the structure of water with which the molecule interacts. Near‐infrared (NIR) spectroscopy has been proven to be powerful in analyzing the structure of water due to its sensitive response to OH. However, chemometrics is vitally important in the analysis of NIR spectrum of water due to the low resolution of the spectrum and the complexity of the water structures. In this review, chemometric methods for structural analysis of water in aqueous systems, particularly in chemical and biological processes, by NIR spectroscopy were summarized, from the improvement of spectral resolution to the effective extraction of the spectral information of different water structures. Through the changes of the spectral features of the water structures, the structural transformation of proteins, thermo‐responsive polymers, antifreeze agents, as well as the structural variation of water in the transformation were elucidated. Water was proved to be a good probe for analyzing the structure and interactions in aqueous solutions and chemical/biological processes by NIR spectroscopy. [ABSTRACT FROM AUTHOR]

This research presents an innovative selected maintenance model for complex systems that considers the uncertainty in maintenance time (MT) for system components with multiple repairpersons. The computational model of uncertain MT for system components is established. An imperfect maintenance model is introduced, which has many imperfect maintenance levels not only considering do nothing, minimal repair, and replacement but also considering multiple intermediate maintenance levels. Furthermore, the system components maintenance assignment algorithm with multiple repairpersons is proposed to addresses the problem of how to assign multiple maintenance tasks to multiple repairpersons in order to minimize system MT. And it is innovatively integrated into the particle swarm optimization (PSO) to solve the proposed selective maintenance model, which enables heuristic algorithm to efficiently assign the multiple maintenance tasks with multiple repairpersons. The effectiveness and advantages of the proposed model and algorithm are verified by numerical experiments. [ABSTRACT FROM AUTHOR]

The surface‐wrinkled shrinkage structure of spheres is very common and also quite intriguing to explore and reveal the analogous droplet solidification kinetics in the space environment. Here, a liquid‐to‐solid phase transition experiment of floating refractory alloy droplets is designed to study the surface wrinkled shrinkage structures aboard China Space Station with a 10−5 gravity level. The experimental Ti‐Ni‐V alloy droplets undergo an extremely high overheating temperature beyond 1800 K and then achieve a supercooling of 307 K, displaying a strong thermodynamic metastability. The spherical surface deformation structures of this alloy under microgravity coupled with extreme metastable solidification are explored. Moreover, through the active control of metastable rapid solidification, a surface monophasic structure and a B2 structure capable of stress‐induced martensitic transformation are facilitated by wrinkled shrinkage dynamics under microgravity. Their findings shed further light on the surface deformation structures during the microgravity solidification process. [ABSTRACT FROM AUTHOR]

TiO2 is a widely used photoelectric conversion semiconductor material. However, due to its native defects, such as the selective absorption of ultraviolet light and high recombination rate of photogenerated carriers, it exhibits poor photoelectrochemical (PEC) water splitting performance. In this study, intrinsic defect titanium vacancy and semiconductor recombination agents ZnIn2S4 were introduced into an anodization‐annealed TiO2 film (TiO2 NT) to enhance the photoanode activity. The activity‐enhanced TiO2 photoanode (ZIS@TiO2 NT‐EA) was characterized by surface analyses and photoelectrochemical measurements. Mott‐Schottky measurement indicated that the introduction of titanium vacancies into the TiO2 NT changed its semiconductor type from n to p, and significantly reduced its apparent activation energy if compared with the TiO2 NT. In addition, after the ZnIn2S4 nanoparticles were loaded on the TiO2 NT‐EA film, the carrier concentration of the ZIS@TiO2 NT‐EA was nearly 12 times higher than the pristine TiO2 NT. Due to the higher carrier separation efficiency resulting from the formation of p‐n heterojunction between TiO2 and ZnIn2S4, the photocurrent density of the ZIS@TiO2 NT‐EA reached 3.89 mA cm−2 at 1.23 V (vs. RHE), nearly 3 times higher than that of the original TiO2 NT. Amazingly, the maximum applied bias photon‐to‐current efficiency (ABPE) value of the ZIS@TiO2 NT‐EA photoanode reached 2.15 % at 0.496 V (vs. RHE), which is very competitive if compared with all the reported TiO2 film electrodes in the PEC water splitting application. The incident photon‐to current efficiency (IPCE) of the ZIS@TiO2 NT‐EA photoanode was approximately 40.9% at 300 nm, which was about 3 times higher than that of the TiO2 NT (13.6%). To understand these impressive improvements in water splitting, further analyses were conducted on the effect of the increased titanium vacancy concentration in the TiO2 lattice and the formation of p‐n junction between the TiO2 and ZnIn2S4 on the PEC behaviour, as well as on the charge transfer resistance and separation efficiency of carriers. [ABSTRACT FROM AUTHOR]

BACKGROUND: Manganese‐based catalysts were considered the most promising catalysts for low‐temperature selective catalytic reduction (NH3‐SCR) reactions. In this work, a series of Mn3Fe2NbyOx catalysts were synthesized by co‐precipitation method for low‐temperature NH3‐SCR and SO2 tolerance tests. RESULTS: The catalysts were characterized by BET, SEM, XRD, XPS, H2‐TPR, and NH3‐TPD. Mn3Fe2Nb0.01Ox exhibited exceptionally high activity with a conversion of almost 100% from 80°C to 240°C, and a NO conversion of more than 75% at 40°C, while the NO conversion at 140°C in the presence of 100 ppm SO2 remained above 90% for 4 h. CONCLUSION: According to the characterization results, Nb modification can expand the specific surface area of the catalyst, improve the structure of the catalyst, and make the active components on the catalyst surface more dispersed. Moreover, the Nb‐modified catalyst reduced the content of Mn2+ on the catalyst surface and strengthened the electronic interactions between elements. The synergistic effects among Mn, Fe, and Nb facilitate the formation of more chemically adsorbed oxygen, which enhances the reduction capacity of the catalyst. This facilitates the adsorption of NH3 by the catalyst at low temperatures and promotes the process of low‐temperature NH3‐SCR reaction. More importantly, the Nb‐modified catalyst possessed more weak acid sites, and the higher surface acidity was conducive to the inhibition of SO3 generation, which enhanced the sulfur poisoning resistance of the catalyst. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Globally, the rollout of COVID‐19 vaccine had been faced with a significant barrier in the form of vaccine hesitancy. This study adopts a multi‐stage perspective to explore the prevalence and determinants of COVID‐19 vaccine hesitancy, focusing on their dynamic evolutionary features. Guided by the integrated framework of the 3Cs model (complacency, confidence, and convenience) and the EAH model (environmental, agent, and host), this study conducted three repeated national cross‐sectional surveys. These surveys carried out from July 2021 to February 2023 across mainland China, targeted individuals aged 18 and older. They were strategically timed to coincide with three critical vaccination phases: universal coverage (stage 1), partial coverage (stage 2), and key population coverage (stage 3). From 2021 to 2023, the surveys examined sample sizes of 29 925, 6659, and 5407, respectively. The COVID‐19 vaccine hesitation rates increased from 8.39% in 2021 to 29.72% in 2023. Urban residency, chronic condition, and low trust in vaccine developer contributed to significant COVID‐19 vaccine hesitancy across the pandemic. Negative correlations between the intensity of vaccination policies and vaccine hesitancy, and positive correlations between vaccine hesitancy and long COVID, were confirmed. This study provides insights for designing future effective vaccination programs for emerging vaccine‐preventable infectious X diseases. [ABSTRACT FROM AUTHOR]

Numerous policies have been implemented to advance the growth of renewable energy. Nonetheless, certain policies have not yielded the anticipated impact on the progression of renewable energy development. In order to maximize the promotion effect of renewable energy policies, this study proposes a capacity allocation optimization method of wind power generation, solar power and energy storage in power grid planning under different policy objectives. First, based on the policy quantification, grey relation analysis (GRA) is used to calculate the correlation degree of the policy indicators on the planning capacity of renewable energy. Further, a multi‐objective capacity estimation model for wind, solar and energy storage is comprehensively presented. Some highly correlated policy indicators are transformed into the special constraints. And the economy and the stability of the power grid are integrated as the objective function. Meanwhile, the carbon trading and punishment for wind power and solar power abandonment are considered. Finally, the proposed model is solved by NSGA‐II‐PSO (particle swarm optimization) algorithm. The novelty of the algorithm is that the crossover operation of NSGA‐II is replaced by the position updating of particle swarm. The calculation result of the case study can effectively evaluate the optimal planning capacity of renewable energy under different policies, while ensuring the economic and the stability of the power system. The study can provide the reasonable basis and the valid analytical method for the policy formulation and the renewable energy development. [ABSTRACT FROM AUTHOR]

The metastable liquid properties and chemical bonds beyond 2000 K remain a huge challenge for ground‐based research on liquid materials chemistry. We show the strong undercooling capability, metastable liquid properties and surface wave patterns of refractory Nb−Si and Zr−V binary alloys explored in space environment. The floating droplet of Nb82.7Si17.3 eutectic alloy superheated up to 2338 K exhibited an extreme undercooling of 437 K, approaching the 0.2TE threshold for homogeneous nucleation of liquid‐solid reaction. The microgravity state endowed alloy droplets with nearly perfect sphericity and thus ensured the high accuracy to determine metastable undercooled liquid properties. A special kind of swirling flow was induced for liquid alloy owing to Marangoni convection, which resulted in the spiral microstructures on Zr64V36 alloy surface during liquid‐solid phase transition. The coupled impacts of surface nucleation and surface flow brought in a novel olivary shape for these binary alloys. Furthermore, the chemical bonds and atomic structures of high temperature liquids were revealed to understand the liquid properties in outer space circumstances. [ABSTRACT FROM AUTHOR]

Bone morphogenetic protein (BMP) signaling plays a vital role in differentiation, organogenesis, and various cell processes. As a member of TGF‐β superfamily, the BMP initiation usually accompanies crosstalk with other signaling pathways and simultaneously activates some of them. It is quite challenging to solely initiate an individual pathway. In this study, an opsin‐free optical method to specifically activate BMP receptors (BMPR) and subsequent pSmad1/5/8 cascades by a single‐time scan of a tightly‐focused femtosecond laser in the near infrared range is reported. Via transient two‐photon excitation to intrinsic local flavins near the cell membrane, the photoactivation drives conformational changes of preformed BMPR complexes to enable their bonding and phosphorylation of the GS domain in BMPR‐I by BMPR‐II. The pSmad1/5/8 signaling is initiated by this method, while p38 and pSmad2 are rarely perturbed. Based on a microscopic system, primary adipose‐derived stem cells in an area of 420 × 420 µm2 are photoactivated by a single‐time laser scanning for 1.5 s and exhibit pSmad1/5/8 upregulation and osteoblastic differentiation after 21 days. Hence, an opsin‐free, specific, and noninvasive optical method to initiate BMP signaling, easily accomplished by a two‐photon microscope system is reported. [ABSTRACT FROM AUTHOR]

Although rechargeable aqueous zinc batteries are cost effectiveness, intrinsicly safe, and high activity, they are also known for bringing rampant hydrogen evolution reaction and corrosion. While eutectic electrolytes can effectively eliminate these issues, its high viscosity severely reduces the mobility of Zn2+ ions and exhibits poor temperature adaptability. Here, we infuse acetamide molecules with Lewis base and hydrogen bond donors into a solvated shell of Zn[(H2O)6]2+ to create Zn(H2O)3(ace)(BF4)2. The viscosity of 1ace‐1H2O is 0.032 Pa s, significantly lower than that of 1ace‐0H2O (995.6 Pa s), which improves ionic conductivity (9.56 mS cm−1) and shows lower freezing point of −45 °C, as opposed to 1ace‐0H2O of 4.04 mS cm−1 and 12 °C, respectively. The acidity of 1ace‐1H2O is ≈2.8, higher than 0ace‐1H2O at ≈0.76, making side reactions less likely. Furthermore, benefiting from the ZnCO3/ZnF2‐rich organic/inorganic solid electrolyte interface, the Zn || Zn cells cycle more than 1300 hours at 1 mA cm−2, and the Zn || Cu operated over 1800 cycles with an average Coulomb efficiency of ≈99.8 %. The Zn || PANI cell cycled over 8500 cycles, with a specific capacity of 99.8 mAh g−1 at 5 A g−1 at room temperature, and operated at −40 °C with a capacity of 66.8 mAh g−1. [ABSTRACT FROM AUTHOR]

Summary: Grain size and weight determine rice yield. Although numerous genes and pathways involved in regulating grain size have been identified, our knowledge of post‐transcriptional control of grain size remains elusive. In this study, we characterize a rice mutant, decreased grain width and weight 1 (dgw1), which produces small grains. We show that DGW1 encodes a member of the heterogeneous nuclear ribonucleoprotein (hnRNP) family protein and preferentially expresses in developing panicles, positively regulating grain size by promoting cell expansion in spikelet hulls. Overexpression of DGW1 increases grain weight and grain numbers, leading to a significant rise in rice grain yield. We further demonstrate that DGW1 functions in grain size regulation by directly binding to the mRNA of Grain Width 6 (GW6), a critical grain size regulator in rice. Overexpression of GW6 restored the grain size phenotype of DGW1‐knockout plants. DGW1 interacts with two oligouridylate binding proteins (OsUBP1a and OsUBP1b), which also bind the GW6 mRNA. In addition, the second RRM domain of DGW1 is indispensable for its mediated protein‐RNA and protein–protein interactions. In summary, our findings identify a new regulatory module of DGW1‐GW6 that regulates rice grain size and weight, providing important insights into the function of hnRNP‐like proteins in the regulation of grain size. [ABSTRACT FROM AUTHOR]

Structural health monitoring (SHM) plays an increasingly vital role in guaranteeing the operation success of marine and offshore (MO) structures while reducing their risks of structural failure. In this study, a real‐time MO‐SHM system based on the highly controllable underwater robots is developed, which is functionalized with three modules, that is, underwater monitoring robots, vision‐based image processing and analyzing, and time‐dependent damage assessing and early warning. The robotic module is actuated by the hybrid driving method that combines the combustion‐based actuators (ejection) and propeller thrusters (propulsion) for transient actuation ability and well reliability in complex underwater environments. The image processing and analyzing module is conducted based on the You Only Look Once (YOLO)‐Underwater model that is expanded by the transfer learning and attention mechanisms and the underwater preconditioning and warning correction added for the specific underwater concrete identification. The damage assessing and early warning module is achieved by the time‐dependent hybrid analytic hierarchy process method that is integrated with the ordered weighted averaging and entropy weight method for more objective assessment and feedback. The reported MO‐SHM system provides design guidance for the next‐generation multifunctional underwater devices that combine analyzing and early warning for underwater concrete structures. [ABSTRACT FROM AUTHOR]

This letter proposes a N‐way planar power divider/combiner using a combination of a Gysel power divider and a ring coupler. This innovative approach enables the realization of a fully planar multiway (>2) Gysel power divider. By replacing the common point of the conventional Gysel power divider with a ring coupler, the entire symmetrical divider can be implemented on a two‐layer printed circuit board. To validate the design concept, an eight‐way planar power divider is designed, fabricated, and tested. Experimental results obtained within the frequency range of 5.10–7.25 GHz (34.8% fractional bandwidth) demonstrate excellent performance. The insertion loss is below 1.24 dB, the input port return loss exceeds 12.65 dB, the output ports exhibit return loss greater than 14.83 dB, the isolation exceeds 22.41 dB, and the maximum measured phase imbalance is within ±2.7°. [ABSTRACT FROM AUTHOR]

An angle sensitive transmission metasurface unit structure is designed in this paper. The metasurface unit presents a good transmission performance for the TE wave incidence, and has a linear phase response with the maximum phase difference up to 180° when the incidence angle changes in the range of −45° and +45°. Moreover, a reconfigurable design of the metasurface unit is realized by loading a varator, and the phase difference is extended to 270° to satisfy the demand of multibit metasurface. Based on the characteristics of angle sensitivity and reconfigurability of the metasurface unit, combined with the control of the varactor and the unit tilt angle, a new 1‐bit digital coding angle sensitive metasurface is proposed. The metasurface has a specification of 20 × 20 and a center frequency of 10 GHz. Both the simulation and measurement show that different transmission is realized for incident waves at different incident angles. It can form different beams, which can be used for multibeam modulation with the same frequency and same polarization. [ABSTRACT FROM AUTHOR]

In order to solve the collaborative optimization scheduling of multi‐microgrid under the high penetration rate of new energy, this paper considered the energy interaction between micro‐grids in multi‐microgrid and the relationship between new energy consumption and electricity cost, constructed a collaborative scheduling model considering both micro‐grid load and main grid wind and optical energy storage, proposed objective function based on economic cost, and improved Genetic Algorithm (GA). The elite thought and catastrophe thought are used to optimize the selection operation, and the particle swarm optimization algorithm is used to optimize the mutation operation. Furthermore, three scenarios were selected to verify the effectiveness of the proposed model and the improved GA. The results show that the proposed model can ensure the stable operation of the multi‐microgrid system with a high proportion of new energy access and reduce the operation cost. In addition. the improved algorithm solves the problems of easy to fall into local optimum and slow iteration speed, and has better performance in solving the model. [ABSTRACT FROM AUTHOR]

This paper presents a reliability evaluation method for distribution network with distributed generations considering feeder fault recovery and network reconfiguration, and mainly addresses issues: 1) insufficient consideration of the characteristics for the components and distributed generations (DGs) of distribution network such as time sequences, randomness and intermittency; 2) changes in the feeder area of the distribution network after the access of DGs; and 3) multi‐dimensional reliability index for distribution network with DGs has not been formed perfectly. Firstly, Markov reliability model for distribution network components/DGs is established in our study. Then, considering the fault recovery and network reconfiguration of the feeder area, island partitioning method of distribution network with DGs is also proposed. Moreover, a reliability evaluation model is presented for distribution network with DGs based on sequential Monte Carlo method. Case study is performed on the improved IEEE RBTS BUS6 F4 feeder system, and the research results indicate the validity and effectiveness of the proposed method. In addition, the system reliability indicators, such as system average interruption frequency index (SAIFI), system average interruption duration index (SAIDI), customer average interruption duration index (CAIDI), and average system availability index (ASAI), are studied and discussed in detail from three dimensions: the access of DGs, the types of DGs, and the capacity of DGs. [ABSTRACT FROM AUTHOR]

Underwater vehicles have opened a unique path to multifunctionality and environmental adaptability. However, inadequate studies have been conducted to investigate the dynamic principle and performance of underwater vehicles in real applications with complex external conditions. Here, we propose a type of combustion‐enabled underwater vehicles that can perform stable high‐speed motions under dynamic fluid environment. Experiments are conducted to test the kinematic performance. Numerical simulations are developed to investigate the fluid–solid interaction phenomenon, and theoretical modeling is derived to study the dynamic principle of the combustion actuation process. The experimental, numerical, and theoretical results are compared with satisfactory agreements. The underwater vehicles perform ~3.4 body‐length distance within 0.2 s and a maximum speed of ~30 body‐length per second in horizontal direction. Parametric studies are conducted to investigate the sensitivity of the key factors to the kinematic performance of the reported underwater vehicles. In the end, we report the hybrid combustion‐enabled underwater vehicles (CUVs) that combined with propeller to realize continuous driving for multi‐mode operations. The experimental, numerical, and theoretical results indicate that hybrid CUVs can achieve more flexible and controllable motion performance. [ABSTRACT FROM AUTHOR]

This study considers the problem of detecting range‐spread targets embedded in subspace interference plus Gaussian clutter with an unknown covariance matrix. The target and interference signals are modeled in terms of deterministic signals belonging to two known subspaces, respectively. Based on the Gradient test criterion, two adaptive detectors are devised for rejecting subspace interference in homogeneous and partially homogeneous environments, respectively. Both of the proposed detectors theoretically exhibit a desirable property of a constant false alarm rate with respect to the clutter covariance matrix as well as the power level. Furthermore, the numerical results show that, compared with their existing counterparts, the proposed detectors exhibit better detection performance and satisfactory suppression performance for the interference. [ABSTRACT FROM AUTHOR]

In situ X‐ray computed tomography (X‐ray CT) is used to investigate the effects of characteristic microstructural features on the pitting initiation and propagation in austenitic stainless steel specimens prepared with laser powder bed fusion (LPBF) additive manufacturing. In situ X‐ray CT in probing the mechanism and kinetics of localized corrosion is demonstrated by immersing two LPBF specimens with different porosities in an aggressive ferric chloride solution for the evaluation of corrosion. X‐ray CT images are acquired from the specimens after every 8 hours of immersion over an extended period of time (216 hours). Corrosion pit growth is then quantitatively analyzed with a data‐constrained modeling method. The pitting growth mechanism of LPBF stainless steel is found to be different from that of conventional stainless steels. More specifically, the mechanism of corrosion pit initiation is closely correlated with the original lack of fusion porosity (LOF) distribution on the surface of the specimens and preferential pit propagation through the LOF pores inside the specimens. Pit growth kinetics are derived from pit volume changes determined through 3D data analysis. The pit growth kinetics in LPBF specimens are found to vary in the initial pit formation, competitive pit propagation, and the dominant pit growth stages. [ABSTRACT FROM AUTHOR]

To compare the effects of two powders, iron oxide and mineral, on the healing process of asphalt molecules, Fe2O3-asphalt and SiO2-asphalt were constructed by Material Studio software (MS). The mean square displacement, diffusion coefficient, concentration distribution of the asphalt layer, and the thermal conductivity of the two models were analyzed to evaluate the influence of two powders on the diffusion behavior of asphalt molecules on a microlevel. The results show that the effect of Fe2O3 on the diffusion rate of asphalt molecules is greater than that of SiO2 at high temperature, but the effects are similar at low temperature. The diffusion coefficient of the Fe2O3-asphalt model increases faster than that of the SiO2-asphalt model with increasing temperature. Compared with SiO2, Fe2O3 is more conducive to the model's reaching a state of uniform concentration, which is manifested as the rapid repair of cracks on a macrolevel. The thermal conductivity of the Fe2O3-asphalt model is higher than that of the SiO2-asphalt model. [ABSTRACT FROM AUTHOR]

Bulk Ti–Al based alloys with an approximate mass of 30 g are first prepared by electromagnetic levitation. The microstructures and the compression properties of Ti‐45%Al‐z%V alloys (z = 4, 8, and 12, atomic percent) at room and high temperatures are studied by experiments. The relationship between V content and the mechanical properties of γ and α2 intermetallics has been investigated by first‐principle calculations. It is clarified that V addition controls the phase contents and the microstructure characteristics. With the increase of V content, the microstructures of Ti‐45%Al‐4%V and Ti‐45%Al‐12%V are dominated by the phase transformations of α → γ and α → α2, respectively. Ti‐45%Al‐4%V alloy is mainly constituted of fine full lamellar γ phase while Ti‐45%Al‐12%V alloy is composed of coarsening lath α2 phase. Besides, the Young's modulus of Ti‐45%Al‐12%V alloy is smaller than that of Ti‐45%Al‐4%V alloy at 300 K, but the yield stress and ultimate compression stress are larger than that of Ti‐45%Al‐4%V alloy. The differences are attributed to the change of the main phase from γ to α2 and the mechanical properties of crystals changed by V addition. In addition, V addition changes the Young's modulus of α2 crystal from isotropy to anisotropy. [ABSTRACT FROM AUTHOR]

With regard to the problems in the integrated urban construction based on "planning-construction–management," the main issues that include the tight construction cycle, the high operation standards, the relatively extensive range of management data sources, the uneven information control, the relatively significant difficulty of management and control, and so on. In this paper, an integrated urban system of "planning-construction-management" based on the management level of the construction projects is established mainly through the application of the teaching reproduction robot (TRR), the engineering information, management and control procedures, and the system framework and performance. Among them, the management and control cover the design control, the quality supervision, the schedule control module, the safety control, the video monitoring, and the facility movement control. The digital technology is included to achieve an integrated management and control model for the engineering design, construction, and operation in its practical operational form. The introduction of the management and control described above has led to relatively good results for the project by operating on the road project with a public-private partnership (PPP) in the startup area of the Chengdu Tianfu International Airport New Town. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of distributed target detection in partially homogeneous Gaussian clutter whose covariance matrix is unknown but persymmetric. It is assumed that primary data and training data share the same clutter covariance matrix structure but different power levels. The target signal is supposed to lie in a multi‐rank subspace with unknown coordinates. A persymmetric subspace detector is designed based on the generalised likelihood ratio test criteria. It is theoretically demonstrated that the proposed detector possesses constant false alarm rate property with respect to the unknown clutter covariance matrix as well as the power level. Experimental results illustrate the performance advantage of the proposed detector over the existing competitors, especially in training‐limited scenarios. [ABSTRACT FROM AUTHOR]

Based on the steel box girder curve incremental launching project of SW ramp bridge in Harbin East Third Ring Road, the geometric alignment and structural internal force of the steel box girder during the incremental launching process were monitored in the whole process. The curve incremental launching coordinate position control method was adopted, and the relevant parameters were modified according to the site construction situation and the initial stress conditions of the girders, and the corrected theoretical value was used as the control and evaluation basis of the monitoring value. The results showed that the original theoretical deflection value was −33.10 mm, the modified theoretical deflection value was −64.10 mm, and the actual monitoring value was −53.20 mm. The modified theoretical value agreed well with the monitoring value, and the error rate between the monitoring value and the theoretical value under each working condition was −17.82%∼14.48%. The geometric alignment and internal force of the steel box girder met the monitoring requirements, ensuring that the steel box girder can meet the design requirements under various working conditions. [ABSTRACT FROM AUTHOR]

Knowledge of the paleoclimatic record of the northeastern Tibetan Plateau (NETP) can potentially improve our understanding of the evolution of the Asian summer monsoon (ASM). However, the history of climate change and inferred spatial extent of the ASM on the NETP since the last deglaciation remain unclear. Here, we use several environmental proxies from the sediments of Hala Lake (beyond the modern limit of ASM), including chironomids, loss‐on‐ignition, grain size and element data, to explore the climatic history of the NETP and the northern boundary of the ASM since the last deglaciation. The results document a series of climatic events during the deglaciation, including Heinrich Event 1, the Bølling–Allerød interstadial and the Younger Dryas event. The records also reveal the timing of the megathermal and precipitation maximum, the lake‐level maximum, and strongest chemical weathering, which occurred during ~10–7 ka. The inferred precipitation maximum during the early Holocene in the Hala Lake basin, which can be verified by the simulated precipitation change, is consistent with that in typical Indian summer monsoon (ISM) regions, suggesting that the ISM has penetrated into Hala Lake basin at that time. The monsoon‐dominated climate in the Hala Lake basin during the early Holocene and the westerlies‐dominated climate in the arid central Asia indicate that the maximum areal extent of the ASM on the NETP since the last deglaciation lay to the northwest of Hala Lake basin. In combination with other published records, the northernmost boundary of the ASM over China since the last deglaciation has been tentatively delineated, to shed some lights on this long‐standing debate. [ABSTRACT FROM AUTHOR]

Background. Virtual reality-based surgery training has become a promising trend in the sector of clinical education. Prior studies have confirmed the effectiveness of VR-based surgical simulators on training surgeons. Most existing papers employing subjective methods explored the students' overall perceptions of surgical skills. However, few studies, from the multidimension perspective of learning performance, investigate how VR improves surgery skills. Participants. 37 college students were recruited in comparative experimental research. The experimental group was equipped with a VR + haptic surgical simulator, while the VR simulator without haptic feedback was used for the control group. Method. The study resorted to physiological approaches to investigate the influence of the VR laparoscopic surgical training system on students' performance. Results. The experimental group scored higher than the control group in flow experience and has better performance in the four dimensions of operation evaluation skills. Conclusion. The study deposited that learners are more likely to exert to flow experience in a learning situation with haptic feedback, which will further improve medical students' performance. [ABSTRACT FROM AUTHOR]

Selective conversion of furfural (FUR) into value‐added chemical commodities are of significance for biomass utilization and sustainable economy. The surface solid acid active sites usually play a crucial role in the valorization of the bio‐renewable substrates. However, the co‐presence of Brønsted and Lewis acid sites on the catalyst would result in the formation of the by‐products of acetalization and hydrogenation of FUR. Herein, acetalization of FUR was realized by virtue of the Brønsted acid sites over phosphate modified amorphous TiO2 (P‐TiO2), while the Lewis acid sites take over under the light irradiation, furfuryl alcohols (FFA) received as the product of transfer hydrogenation. Thus, the by‐products were avoided by the novel strategy of light‐tunable acidity. The feature of reversible, light‐tunable acidity provides the possibility to control the reactivity and insights for the blueprint of a one‐pot tandem catalytic system. [ABSTRACT FROM AUTHOR]

The strength and ductility trade‐off dilemma has limited the wide application of TiAl‐based alloys. Here, a new insight into the potential for increasing the strength and ductility of a hypoperitectic Ti–48 at% Al–8 at% Nb alloy is accomplished by the electromagnetic levitation (EML) technique. Moreover, a systematic analysis of the primary and subsequent peritectic solidification kinetics is conducted in the undercooling range of 308 K. Assisted by a high‐speed camera, in situ observation of the liquid–solid (primary β‐Ti phase and peritectic α‐Ti phase) interface migration is accomplished. When the alloy melt is undercooled to 240 K, high‐ordered nanotwins are observed in the Ti–48 at% Al–8 at% Nb alloy, which form a unique hierarchical microstructure. Upon further increasing the undercooling, the density of these nanotwins is significantly enhanced. The room‐temperature compression results reveal that the strength and ductility increase up to 140% and 150%, respectively. This is mainly ascribed to the remarkable grain refinement, formation of nanotwins with various orientations, accumulation of dislocations and stacking faults, and retention of the metastable γ‐phase. The superior combination of strength and ductility indicates the possibility to fabricate high‐ordered nanotwins via rapid solidification, thus improving the performance of γ‐TiAl‐based alloys. [ABSTRACT FROM AUTHOR]

The northeastern Qinghai‐Tibet Plateau is strongly influenced by the East Asian summer monsoon (EASM), the Indian summer monsoon (ISM) and the westerlies. However, how these various circulation systems interacted in the region during the Holocene, and the nature of the associated environmental impacts, are unclear and even controversial. Here we present a high‐resolution pollen record from Caodalian Lake since 7.9 ka (1 ka = 1,000 cal yr BP), which is used to reconstruct the regional vegetation history and climatic changes. In addition, we use a novel procedure for pollen‐based quantitative paleoclimatic reconstruction to characterize the evolution of precipitation at Caodalian Lake and nearby Qinghai Lake. The results suggest that mean annual precipitation (Pann) is the most significant factor controlling the fossil pollen record at both sites, and the Pann reconstructions are well correlated with each other (r = 0.72, p < 0.001). A synthesis of the Pann records from the two sites indicates that the precipitation in the region began to increase before 10 ka, reached a maximum during 10–5 ka, and gradually decreased thereafter. We propose that the pattern of precipitation evolution in the Qinghai Lake basin resulted from the combined effects of the ISM and EASM, with a precipitation maximum of 10–7 ka for the ISM and 7–5 ka for the EASM; both systems contributed to the regional precipitation maximum during 10–5 ka. Our well‐dated and unambiguous Pann record also provides the opportunity to reconcile paleoenvironmental reconstructions derived from different paleoenvironmental proxies from the Qinghai Lake basin. Key Points: Unambiguous high‐resolution precipitation record from the Qinghai Lake basinPrecipitation evolution in the Qinghai Lake basin resulted from the combined effects of the East Asian summer monsoon and Indian summer monsoonOstracod δ18O records from Qinghai Lake cannot be used to reflect the intensity of monsoon precipitation [ABSTRACT FROM AUTHOR]

Changes in water storage of the large freshwater lakes in Arid Central Asia (ACA) have significant implications for the regional social and ecological systems. Here we present a lake‐level record of the past 2,000 years from Bosten Lake, a large freshwater body in the region, using the sedimentary Cladoceran microfossil. The results suggest that a lower lake level and a higher salinity occurred during the cold, high‐precipitation periods of 280–450 AD and 1570–1850 AD, and that a higher lake level and a lower salinity occurred during the warm, low‐precipitation period of 450–1570 AD. The findings show that on the centennial timescale, the water‐level fluctuations of Bosten Lake were modulated mainly by temperature‐driven meltwater input. In addition, the shortage of freshwater during the cold period may have contributed to the collapse of the ancient cities and the depression of the trade along the Silk Road. Plain Language Summary: Bosten Lake, the largest inland freshwater lake of China, is located in the northeast part of Tarim Basin. The lake is important freshwater resources and plays an important role in sustaining regional social and ecological systems. In this study, we reconstructed the water‐level fluctuations of the lake over the past 2,000 years, based mainly on the Cladoceran microfossil analyses of a sediment core. The results suggest that a lower lake level occurred during the cold, high‐precipitation periods of 280–450 AD and 1570–1850 AD, and that a higher lake level occurred during the warm, low‐precipitation period of 450–1570 AD. The findings show that on the centennial timescale, the water‐level fluctuations of Bosten Lake were modulated mainly by temperature‐driven meltwater input. In addition, historical documents reveal that a large number of ancient cities in the Tarim Basin were abandoned in the third‐sixth centuries and that the trade along the ancient Silk Road was relatively depressed during that time, coinciding with the salinization and the shrinking of Bosten Lake. This suggests that the shortage of freshwater during this cold period may have contributed to the collapse of the ancient cities and the depression of the trade along the Silk Road. Key Points: On the centennial timescale, the water‐level fluctuations of Bosten Lake were modulated mainly by temperature‐driven meltwater inputThe shortage of freshwater during the cold period may have contributed to the collapse of the ancient cities along the Silk Road [ABSTRACT FROM AUTHOR]

At present, virtual reality (VR) ‐based medical simulators provide an efficient and cost‐effective alternative without exposing risk to the traditional training approaches. As an essential and indispensable task in fundamental surgical skills training, the research of suturing simulation still remains insufficient in the field of virtual surgery. In this paper, we present a real‐time suturing simulation framework which can handle the complex interactions between surgical instruments and soft tissue. The simulation consists of two stages: external interaction and internal coupling. External interaction involves the interplay between needle/suture and the soft tissue, which are both deformed by position‐based dynamics (PBD) with different constraints. At the internal coupling stage, once the force exceeds a threshold, the needle tip will puncture and penetrate into the soft tissue and generate a path. To guarantee the needle/suture accurately following the path inside the soft tissue, we propose a novel coupling method by matching and generating the constraints among needle, suture, and penetration path. We have applied this suturing simulation into a VR laparoscopic surgery simulator with haptic force. Our experimental results demonstrate that our approach can achieve real‐time performance with a high degree of visual realism and haptic fidelity. [ABSTRACT FROM AUTHOR]

Reduced amorphous TiO2 (A‐TiO2), with high coverage of electrons and protons on its surface, supplies a steady‐state condition for selective hydrogenation reaction. Generally, there are some complex hydrogenation reaction products ascribed to the presence of multiple adsorption modes of cinnamaldehyde (CAL). In our work, the saturated aldehyde (∼48%) and unsaturated alcohol (52%) coexist in the products with a ratio of near 1 : 1, while the saturated alcohol is not produced in the reaction. Furthermore, the presence of H2O could suppress the adsorption of the C=O group while the C=C group could be strongly adsorbed on the surface of A‐TiO2, which results in the high selectivity of HCAL (∼84%). We explain these results by proposing a reaction mechanism with several adsorption modes of CAL affected by the solvents. This discovery also puts forward a new method for promoting the selectivity of COL by removing the H2O in the reaction system. [ABSTRACT FROM AUTHOR]

Converting N2 into NH3 under mild conditions is a great challenge because of the highly stable N≡N bond and the difficult chemisorption of N2 at the active site. Herein, we report that MoO2/BiOCl composites realized excellent photocatalytic nitrogen fixation efficiency when water was used proton source. The strong interaction between BiOCl nanoplates and MoO2 nanosheets regulated the electronic structure of the interface and provided active sites for the catalytic reaction. The Mo−O−Bi bonds formed at the interface of MoO2 and BiOCl worked as the bridge of electrons, facilitating the separation and migration of photo‐generated charge carriers. In addition, the interface of MoO2/BiOCl composite also promoted the adsorption and activation of N2, substantially enhanced N2 reduction. As a result, ammonia production rate of 35 μmol g−1 h−1 was achieved, which is 8‐fold higher than that of pristine BiOCl and 6‐fold higher than that of MoO2. This work presents a feasible route to design the nanocomposites with better performance for photocatalytic nitrogen fixation. [ABSTRACT FROM AUTHOR]

The various morphology and structure microspheres were fabricated via one‐step single‐solvent electrospraying of hydrophilic and hydrophobic block modified copolymer of polycaprolactone (PCL). A honeycomb‐like hierarchical structure microspheres of PCL‐b‐PTFOA(4h) and abundant nanometer pores of PCL‐b‐PEG400 microspheres were obtained due to the solvent evaporation, thermally and polymer diffusion‐induced phase separation effect. Furthermore, a superhydrophobic coatings and robust superhydrophobic‐coated cotton woven fabric surfaces were prepared by using PCL‐b‐PTFOA(4h) microspheres with hierarchical structure and low surface energy. The contact angle (CA) and sliding angle (SA) of PCL‐b‐PTFOA(4h) microspheres‐coated cotton woven fabric surfaces reached 164.4 ± 5.5° and 6.8 ± 0.5°, respectively, which allows for self‐cleaning. The self‐cleaning test demonstrated that the coated superhydrophobic surface could shed aqueous dyes and dust without any trace. The superhydrophobic‐coated fabric shows good soaping fastness against mechanical abrasion without significant reduction of CA. This electrospraying coating of block copolymers can provide a simple, facile, and promising technique for producing multifunctional textiles. [ABSTRACT FROM AUTHOR]

Abstract: Polymeric microspheres can serve as microcarrier matrices and be used to prepare fabric coatings. After embedding spices or drugs in microspheres, and using them to coat fabrics, the coated fabrics can be applied to functional textiles. A facile one‐step, single‐solvent electrospray technology is utilized to produce polycaprolactone (PCL), PCL‐PEG400, and PCL‐PEG1000 microspheres with controlled sizes and tunable surface morphologies by adjusting parameters such as flow rate, voltage, and collection distance. Scanning electron microscopy coupled with an image analysis software (ImageJ) is employed to evaluate the size distribution and structures of the microspheres. Using PCL, PCL‐PEG400, and PCL‐PEG1000 as matrices, spherical particles with micro‐nanostructure surfaces are produced by adjusting the electrospraying parameters. According to observation and analysis results, PCL, PCL‐PEG400, and PCL‐PEG1000 form different microspheres with many porous pits, few pits, or nonporous wrinkles on a spherical surface, respectively. Increasing the flow rate or voltage produces larger or smaller microspheres, respectively. A slight increase in the average particle size is obtained by increasing the collection distance. Cotton fabrics pretreated with adhesive are directly coated by electrospraying to successfully enhance microsphere adhesion on fabric surfaces. [ABSTRACT FROM AUTHOR]

Rapid solidification of highly undercooled Fe–Co–Ni alloys is realized by drop tube technique. The microstructures of Fe–10%Co–10%Ni, Fe–15.6%Co–12%Ni, and Fe–10%Co–20%Ni alloys are all composed of single α(Fe) solid solution phase, which are confirmed by the results of XRD and DSC. With the decrease of droplet diameters, the cooling rate and undercooling increase, meanwhile, the microstructural characteristic of α(Fe) phase transforms from coarse dendrites to equiaxed grains. The size of coarse dendrites decreases to one tenth for the refined equiaxed grains. Employing the Vickers hardness and nano indenter techniques, the mechanical properties of α(Fe) dendrites are investigated. The average Vickers microhardness of α(Fe) phase is remarkably enhanced with the decrease of the grain size. Due to the more homogenous solute distribution in the dendrite trunks, the nanohardness presents a gentle fluctuation. Once the droplet diameter exceeds a critical value, the solutes concentrate at the grain boundaries. As a result, the closer the indenters to the grain boundary, the larger the nanohardness. [ABSTRACT FROM AUTHOR]

ABSTRACT We investigate chironomid assemblages in a sediment core from Gonghai Lake, which is located on the East Asian summer monsoon (EASM) boundary in northern China, to quantify EASM variability during the past 13.5 ka BP. Six significantly different chironomid assemblage zones indicate that maximum precipitation and water depth occurred in the mid-Holocene (8270-2700 cal a BP) and the minimum period was the past 1250 years. A modern dataset of 44 lakes near Gonghai Lake was sampled to calibrate the response of chironomid assemblages to precipitation. Our results demonstrate that mean annual precipitation is the most significant environmental variable influencing modern chironomid assemblages in this monsoonal region. Maximum EASM precipitation in the mid-Holocene, indicated by chironomid assemblages in the monsoon fringe, contrasts with the early Holocene EASM maximum suggested by stalagmite δ18O data from southern China, but is consistent with other evidence. Our findings are compatible with the proposal that the stalagmite δ18O variations in southern China may not reliably reflect the evolution of EASM since the last deglaciation. [ABSTRACT FROM AUTHOR]

Multiscale nondestructive characterization of coal microscopic physical structure can provide important information for coal conversion and coal-bed methane extraction. In this study, the physical structure of a coal sample was investigated by synchrotron-based multiple-energy X-ray CT at three beam energies and two different spatial resolutions. A data-constrained modeling (DCM) approach was used to quantitatively characterize the multiscale compositional distributions at the two resolutions. The volume fractions of each voxel for four different composition groups were obtained at the two resolutions. Between the two resolutions, the difference for DCM computed volume fractions of coal matrix and pores is less than 0.3%, and the difference for mineral composition groups is less than 0.17%. This demonstrates that the DCM approach can account for compositions beyond the X-ray CT imaging resolution with adequate accuracy. By using DCM, it is possible to characterize a relatively large coal sample at a relatively low spatial resolution with minimal loss of the effect due to subpixel fine length scale structures. [ABSTRACT FROM AUTHOR]

The post-translational modification of histone tails is the principal process controlling epigenetic regulation in eukaryotes. The lysine methylation of histones is dynamically regulated by two distinct classes of enzymes: methyltransferases and demethylases. JMJD5, which plays an important role in cell-cycle progression, circadian rhythms and embryonic cell proliferation, has been shown to be a JmjC-domain-containing histone demethylase with enzymatic activity towards H3K36me2. Here, the crystal structure of human JMJD5 lacking the N-terminal 175 amino-acid residues is reported. The structure showed that the Gln275, Trp310 and Trp414 side chains might block the insertion of methylated lysine into the active centre of JMJD5, suppressing the histone demethylase activity of the truncated JMJD5 construct. A comparison of the structure of JMJD5 with that of FIH, a well characterized protein hydroxylase, revealed that human JMJD5 might function as a protein hydroxylase. The interaction between JMJD5 and the core histone octamer proteins indicated that the histone proteins could be potential substrates for JMJD5. [ABSTRACT FROM AUTHOR]

The article offers a study on Eosestheria which is an important component of the Jehol biota and also an important link in the biota chain during its production period. Topics discussed include survey of sedimentary rock systems in the Wenzhigou areas of Liaoning Province and fossils of Eosestheria were collected. Article concludes the first discovery of the Eosestheria in eastern Liaoning confirms the existence of Jehe biota in this region.

The gene SA239 from Staphylococcus aureus encodes a ribokinase that catalyzes the phosphorylation of d-ribose to produce ribose-5-phosphate. Sa239 was crystallized using the hanging-drop vapour-diffusion method. The crystals diffracted to 2.9 Å resolution and belonged to space group P6122 or P6522, with unit-cell parameters a = b = 91.8, c = 160.7 Å. Preliminary crystallographic analysis revealed that the Matthews coefficient VM was 3.01 Å3 Da−1, indicating the presence of one molecule in the asymmetric unit. [ABSTRACT FROM AUTHOR]