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Spin-orbitronics, exploiting electron spin and/or orbital angular momentum, offers a powerful route to energy-efficient spintronic applications. Recent research on orbital currents in light metals broadens the scope of spin-orbit torque (SOT). However, distinguishing and manipulating orbital torque in heavy metal/ferromagnet (HM/FM) remains a challenge, limiting the promising synergy of spin and orbital currents. Here, we design a HM/FM/FMSOC heterostructure and experimentally separate orbital torque contribution from spin torque by utilizing the distinct diffusion length of spin and orbital currents. Furthermore, we achieve the synergy of spin and orbital torques by controlling their relative strength, and obtain a 110% improvement in torque efficiency compared to the representative Pt/Co bilayer. Our findings not only contribute to a deeper understanding of SOT mechanisms and orbital current transport in HM/FM multilayers, but also highlight the promising prospect of orbital and spin torque synergy for optimizing the efficiency of next-generation spintronic devices. Eliminating the interference of spin current to distinguish and manipulate orbital torque in heavy metal/ferromagnet (HM/FM) heterojunction remains a challenge. Here, the authors design a HM/FM/FMSOC multilayer to separate orbital torque contribution and harness the synergy of spin and orbital currents for enhanced spin-orbit torque. [ABSTRACT FROM AUTHOR]

Ischemia–reperfusion (I/R) injury is a key influencing factor in the outcome of stroke. Inflammatory response, oxidative stress, and neuronal apoptosis are among the main factors that affect the progression of I/R injury. Farrerol (FAR) is a natural compound that can effectively inhibit the inflammatory response and oxidative stress. However, the role of FAR in cerebral I/R injury remains unknown. In this study, we found that FAR reduced brain injury and neuronal viability after cerebral I/R injury. Meanwhile, administration of FAR also reduced the inflammatory response of microglia after brain injury. Mechanistically, FAR treatment directly reduced neuronal death after oxygen glucose deprivation/re-oxygenation (OGD/R) through enhancing cAMP-response element binding protein (CREB) activation to increase the expression of downstream neurotrophic factors and anti-apoptotic genes. Moreover, FAR decreased the activation of nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, inhibited microglia activation, and reduced the production of inflammatory cytokines in microglia after OGD/R treatment or LPS stimulation. The compromised inflammatory response by FAR directly promoted the survival of neurons after OGD/R. In conclusion, FAR exerted a protective effect on cerebral I/R injury by directly decreasing neuronal death through upregulating CREB expression and attenuating neuroinflammation. Therefore, FAR could be a potentially effective drug for the treatment of cerebral I/R injury. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable batteries (ARBs) are generally safer than non-aqueous analogues, they are also less-expensive, and more friendly to the environment. However, the inherent disadvantage of the narrow electrochemical window of H2O seriously restricts the energy density and output voltage of ARBs, especially aqueous rechargeable Fe-based batteries. Herein, we introduce a new battery system: the anode contains C@Fe/Fe2O3 composite, which is interfaced with an alkaline electrolyte; the cathode contains LiMn2O4 in contact with a neutral electrolyte. A Li+-conducting membrane is carefully selected to decouple the electrode-electrolyte, which effectively widens the electrochemical window to above 2.65 V, thereby enables an aqueous rechargeable iron battery. Its average output voltage is 1.83 V and its energy density is 235.3 Wh/kg at 549 W/kg. In this work, we propose the energy storage mechanism with the aid of density functional theory (DFT). The calculated reduction potential of the anode agrees with the experimental value. Furthermore, this battery system demonstrates long cycle lifespan of approximately 2500 cycles at 2 A/g, corresponding to a capacity retention of 82.1%. These results are very far superior than those of mainstream aqueous rechargeable Fe-based batteries, which guarantee future investigation for storing electricity energy. [ABSTRACT FROM AUTHOR]

Stretchable neuromorphic optoelectronics present tantalizing opportunities for intelligent vision applications that necessitate high spatial resolution and multimodal interaction. Existing neuromorphic devices are either stretchable but not reconcilable with multifunctionality, or discrete but with low-end neurological function and limited flexibility. Herein, we propose a defect-tunable viscoelastic perovskite film that is assembled into strain-insensitive quasi-continuous microsphere morphologies for intrinsically stretchable neuromorphic vision-adaptive transistors. The resulting device achieves trichromatic photoadaptation and a rapid adaptive speed (<150 s) beyond human eyes (3 ~ 30 min) even under 100% mechanical strain. When acted as an artificial synapse, the device can operate at an ultra-low energy consumption (15 aJ) (far below the human brain of 1 ~ 10 fJ) with a high paired-pulse facilitation index of 270% (one of the best figures of merit in stretchable synaptic phototransistors). Furthermore, adaptive optical imaging is achieved by the strain-insensitive perovskite films, accelerating the implementation of next-generation neuromorphic vision systems.Wearable neuromorphic optoelectronics require stretchable photosensitive materials and multifunctional integration. Here, authors develop intrinsically stretchable neuromorphic vision-adaptive transistors for skin-like neuromorphic vision systems. [ABSTRACT FROM AUTHOR]

Challenges associated with stretchable optoelectronic devices, such as pixel size, power consumption and stability, severely brock their realization in high-resolution digital imaging. Herein, we develop a universal detachable interface technique that allows uniform, damage-free and reproducible integration of micropatterned stretchable electrodes for pixel-dense intrinsically stretchable organic transistor arrays. Benefiting from the ideal heterocontact and short channel length (2 μm) in our transistors, switching current ratio exceeding 106, device density of 41,000 transistors/cm2, operational voltage down to 5 V and excellent stability are simultaneously achieved. The resultant stretchable transistor-based image sensors exhibit ultrasensitive X-ray detection and high-resolution imaging capability. A megapixel image is demonstrated, which is unprecedented for stretchable direct-conversion X-ray detectors. These results forge a bright future for the stretchable photonic integration toward next-generation visualization equipment. Pixel size, power consumption, and stability of stretchable optoelectronic devices limit their application in digital imaging. Bian et al. developed a universal detachable interface technique for damage-free micropattern, reproducible transfer and ideal heterocontact of intrinsically stretchable electrodes. [ABSTRACT FROM AUTHOR]

The ground state search of the Ising model can be used to solve many combinatorial optimization problems. Under the current computer architecture, an Ising ground state search algorithm suitable for hardware computing is necessary for solving practical problems. Inspired by the potential energy conversion of the springs, we propose the Spring-Ising Algorithm, a point convolutional neural network algorithm for ground state search based on the spring vibration model. Spring-Ising Algorithm regards the spin as a moving mass point connected to a spring and establishes the equation of motion for all spins. Spring-Ising Algorithm can be mapped on AI chips through the basic structure of the neural network for fast and efficient parallel computing. The algorithm has shown promising results in solving the Ising model and has been tested in the recognized test benchmark K2000. The optimal results of this algorithm after 10,000 steps of iteration are 2.9% of all results. The algorithm introduces the concept of dynamic equilibrium to achieve a more detailed local search by dynamically adjusting the weight of the Ising model in the spring oscillation model. Spring-Ising Algorithm offers the possibility to calculate the Ising model on a chip which focuses on accelerating neural network calculations. [ABSTRACT FROM AUTHOR]

Understanding symmetry-breaking states of materials is a major challenge in the modern physical sciences. Quantum atmosphere proposed recently sheds light on the hidden world of these symmetry broken patterns. Yet, no experiment has been performed to demonstrate its potential. In our experiment, we prepare time-reversal-symmetry conserved and broken quantum atmosphere of a single nuclear spin and successfully observe their symmetry properties. Our work proves in principle that finding symmetry patterns from quantum atmosphere is conceptually viable. It also opens up entirely new possibilities in the potential application of quantum sensing in material diagnosis. [ABSTRACT FROM AUTHOR]

Solving the inverse kinematics of redundant and hyper-redundant manipulators is more challenging because their kinematic redundancy leads to a more complicated mapping from end-effector pose to configuration space. A heuristic inverse kinematics solver, called Forward And Backward Reaching Inverse Kinematics (FABRIK), has been demonstrated to solve the inverse kinematics of complex chain systems with fast convergence and simple implementation. However, as the pose precision of the end-effector increases to a higher value, such as 10 - 6 , FABRIK converges slowly in some configurations and thus exhibits unstable convergence behavior. Hence, this paper presents a novel inverse kinematics algorithm that combines FABRIK and the sequential quadratic programming (SQP) algorithm, in which the joint angles deduced by FABRIK will be taken as the initial seed of the SQP algorithm to realize fast convergence. Meanwhile, a universal and non-trivial mapping from joint Cartesian positions to joint angles is included to enable the extension of FABRIK to redundant and hyper-redundant manipulators while retaining its simplicity. With the 10 - 6 pose error constraint, quantitative tests on serial chain manipulators demonstrate that the combined algorithm outperforms FABRIK in terms of success rate and runtime. Meanwhile, some popular inverse kinematics algorithms are treated as benchmarks to compare with the combined algorithm. Finally, simulations using serial chain manipulators indicate the effectiveness of the combined algorithm on path tracking. [ABSTRACT FROM AUTHOR]

Polymer nanowire (NW) organic field-effect transistors (OFETs) integrated on highly aligned large-area flexible substrates are candidate structures for the development of high-performance flexible electronics. This work presents a universal technique, coaxial focused electrohydrodynamic jet (CFEJ) printing technology, to fabricate highly aligned 90-nm-diameter polymer arrays. This method allows for the preparation of uniformly shaped and precisely positioned nanowires directly on flexible substrates without transfer, thus ensuring their electrical properties. Using indacenodithiophene-co-benzothiadiazole (IDT-BT) and poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8-BT) as example materials, 5 cm2 arrays were prepared with only minute size variations, which is extremely difficult to do using previously reported methods. According to 2D-GIXRD analysis, the molecules inside the nanowires mainly adopted face-on π-stacking crystallite arrangements. This is quite different from the mixed arrangement of thin films. Nanowire-based OFETs exhibited a high average hole mobility of 1.1 cm2 V−1 s−1 and good device uniformity, indicating the applicability of CFEJ printing as a potential batch manufacturing and integration process for high-performance, scalable polymer nanowire-based OFET circuits. This technique can be used to fabricate various polymer arrays, enabling the use of organic polymer semiconductors in large-area, high-performance electronic devices and providing a new path for the fabrication of flexible displays and wearable electronics in the future. [ABSTRACT FROM AUTHOR]

Physical reservoirs holding intrinsic nonlinearity, high dimensionality, and memory effects have attracted considerable interest regarding solving complex tasks efficiently. Particularly, spintronic and strain-mediated electronic physical reservoirs are appealing due to their high speed, multi-parameter fusion and low power consumption. Here, we experimentally realize a skyrmion-enhanced strain-mediated physical reservoir in a multiferroic heterostructure of Pt/Co/Gd multilayers on (001)-oriented 0.7PbMg1/3Nb2/3O3−0.3PbTiO3 (PMN-PT). The enhancement is coming from the fusion of magnetic skyrmions and electro resistivity tuned by strain simultaneously. The functionality of the strain-mediated RC system is successfully achieved via a sequential waveform classification task with the recognition rate of 99.3% for the last waveform, and a Mackey-Glass time series prediction task with normalized root mean square error (NRMSE) of 0.2 for a 20-step prediction. Our work lays the foundations for low-power neuromorphic computing systems with magneto-electro-ferroelastic tunability, representing a further step towards developing future strain-mediated spintronic applications. An energy-efficient physical reservoir is crucial for reservoir computing (RC). Here the authors demonstrate an all-electric skyrmion-enhanced strain-mediated physical RC system and achieve a benchmark chaotic time series prediction. [ABSTRACT FROM AUTHOR]

The nitrogen (N) demand–supply is crucial for optimizing nutrient management in orchards. However, some knowledge gaps remain regarding the exact magnitude of N demand and the relative contribution of native soil N, fertilizer N and reserve N to tree growth in the field. Sequential destructive sampling, N difference method, and 15N-labeled fertilizer were combined to quantify N uptake and sources in an apple orchard from 2019 to 2021. The annual N requirement for young dwarf apple trees was 9–11 kg ha−1, while the N supply had little effect on their demand, uptake, and partitioning. Approximately 80% of the N was absorbed between the end of spring shoot growth and nutrient withdrawal in 2019–2020. In 2020–2021, 59% and 21% of the total N uptake occurred during spring shoot slow growth to cessation and autumn shoot growth to nutrient withdrawal, respectively. At nutrient withdrawal, N storage of apple trees was 3 kg ha−1 in 2019–2020, contributing to 25% of the total N, and 7.8 kg ha−1 in 2020–2021, contributing to 44% of the total N. Apple trees acquired 81% of N from the soil when fertilizer was supplied, i.e., 8.6 and 7.2 kg ha−1 N in the first and following year, respectively. Throughout the growing season, the amount of N fertilization should be coupled with the seasonal N uptake by trees. Native soil N, not chemical fertilizer, is the primary N source in young apple orchards. A better balance of N fertilizer inputs, native soil N supply, and N demand for apple trees is needed to minimize associated environmental impacts. [ABSTRACT FROM AUTHOR]

Predicting urban crowd flow spatial distributions plays a critical role in optimizing urban public safety and traffic congestion management. The spatial dependency between regions and the temporal dynamics of the local crowd flow are two important features in urban crowd flow prediction. However, few studies considered geographic characteristic in terms of spatial features. To fill this gap, we propose an urban crowd flow prediction model integrating geographic characteristics (FPM-geo). First, three geographic characteristics, proximity, functional similarity, and road network connectivity, are fused by a residual multigraph convolution network to model the spatial dependency relationship. Then, a long short-term memory network is applied as a framework to integrate both the temporal dynamic patterns of local crowd flow and the spatial dependency between regions. A 4-day mobile phone dataset validates the effectiveness of the proposed method by comparing it with several widely used approaches. The result shows that the root mean square error decreases by 15.37% compared with those of the typical models with the prediction interval at the 15-min level. The prediction error increases with the crowd flow size in a local area. Moreover, the error reaches the top of the morning peak and the evening peak and slopes down to the bottom at night. [ABSTRACT FROM AUTHOR]

Large area and highly aligned polymer semiconductor sub-microwires were fabricated using the coaxial focused electrohydrodynamic jet printing technology. As indicated by the results, the sub-microwire arrays have smooth morphology, well reproducibility and controllable with a width of ~110 nm. Analysis shows that the molecular chains inside the sub-microwires mainly exhibited edge-on arrangement and the π-stacking direction (010) of the majority of crystals is parallel to the long axis of the sub-microwires. Sub-microwires based organic field effect transistors showed high mobility with an average of 1.9 cm2 V−1 s−1, approximately 5 times higher than that of thin film based organic field effect transistors. In addition, the number of sub-microwires can be conveniently controlled by the printing technique, which can subsequently concisely control the performance of organic field effect transistors. This work demonstrates that sub-microwires fabricated by the coaxial focused electrohydrodynamic jet printing technology create an alternative path for the applications of high-performance organic flexible device. Here, the authors fabricate large area and highly aligned polymer semiconductor sub-microwires arrays via coaxial focused electrohydrodynamic jet printing technology, achieving high on/off ratio and average mobility that is 5x higher than that of thin film based organic field effect transistors. [ABSTRACT FROM AUTHOR]

Developing convenient and accurate SARS-CoV-2 antigen test and serology test is crucial in curbing the global COVID-19 pandemic. In this work, we report an improved indium oxide (In2O3) nanoribbon field-effect transistor (FET) biosensor platform detecting both SARS-CoV-2 antigen and antibody. Our FET biosensors, which were fabricated using a scalable and cost-efficient lithography-free process utilizing shadow masks, consist of an In2O3 channel and a newly developed stable enzyme reporter. During the biosensing process, the phosphatase enzymatic reaction generated pH change of the solution, which was then detected and converted to electrical signal by our In2O3 FETs. The biosensors applied phosphatase as enzyme reporter, which has a much better stability than the widely used urease in FET based biosensors. As proof-of-principle studies, we demonstrate the detection of SARS-CoV-2 spike protein in both phosphate-buffered saline (PBS) buffer and universal transport medium (UTM) (limit of detection [LoD]: 100 fg/mL). Following the SARS-CoV-2 antigen tests, we developed and characterized additional sensors aimed at SARS-CoV-2 IgG antibodies, which is important to trace past infection and vaccination. Our spike protein IgG antibody tests exhibit excellent detection limits in both PBS and human whole blood ((LoD): 1 pg/mL). Our biosensors display similar detection performance in different mediums, demonstrating that our biosensor approach is not limited by Debye screening from salts and can selectively detect biomarkers in physiological fluids. The newly selected enzyme for our platform performs much better performance and longer shelf life which will lead our biosensor platform to be capable for real clinical diagnosis usage. [ABSTRACT FROM AUTHOR]

Developing a rapid and sensitive photo-electrochemical (PEC) sensing platform for glucose detection is highly desirable. Herein, a visible light-driven PEC enzyme biosensor for sensitive detection of glucose was proposed, employing reduced graphene oxide/titania (TiO2) nanotubes (RGO/TNTs) as photoactive materials and glucose oxidase (GOD) as the identification element. The RGO/TNTs composites were synthesized via a facile hydrothermal process. Notably, the unique nanostructure system significantly increases the absorption in the visible region and effectively separates the photo-generated electron–hole pairs, which is essential for promoting the PEC activity. In the presence of dissolved oxygen, the GOD immobilized on the modified electrode could specifically catalyze the electro-oxidation of glucose to produce H2O2, resulting in an increase of photocurrent intensity. Based on the variation of the photocurrent response, the constructed PEC enzyme biosensor exhibited high sensitivity with a wide linear range from 10–2 to 10 mM and a low detection limit of 5.0 μΜ. Meanwhile, the potential applicability of the PEC enzyme biosensor was evaluated by detecting glucose in human serum samples, and satisfactory results were obtained. The PEC enzyme biosensor based on RGO/TNTs composites successfully realized the sensitive detection of glucose and displayed good selectivity, high stability and satisfactory repeatability. [ABSTRACT FROM AUTHOR]

Objective: To analyze the prevalence of hypertension-mediated organ damage (HMOD) and its relationship with enzyme activity of mutant CYP17A1 and other risk factors in patients with 17α-hydroxylase/17,20-lyase deficiency (17-OHD). Methods: A total of 68 patients with 17-OHD were recruited in the Peking Union Medical College Hospital from 2003 to 2021. The incidence of hypertension and HMOD was respectively analyzed. CYP17A1 sequencing was performed and the enzyme activity of mutant CYP17A1 was determined by analyzing the characteristics of mutation itself and the functional data reported previously. A logistic regression model was employed to analyze the factors related to HMOD and the specific damaged organs in 17-OHD patients. Result(s): Sixty-five patients (95.6%) exhibited hypertension, 32 of whom were diagnosed with HMOD. c.985_987delTACinsAA (p.Y329KfsX418) (53.8%) and c.1459_1467del (p. del D487_F489) (11.4%) were the top two mutations, and no correlation was found between enzyme activity of mutant CYP17A1 and HMOD. The risk of HMOD increased by 32% for each additional year of hypertension duration, 10.2-fold for each one-grade increase in hypertension level, 2.3-fold for each grade of exacerbation of hypokalemia. Conclusion: Patients with 17-OHD experience a high incidence of HMOD. There was no correlation between the HMOD occurrence and enzyme activity of mutant CYP17A1. Longer duration of hypertension, more severe hypertension, and hypokalemia were independent risk factors for the occurrence of HMOD in patients with 17-OHD. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are ideal candidates for beyond-silicon nano-electronics because of their high mobility and low-cost processing. Recently, assembled massively aligned CNTs have emerged as an important platform for semiconductor electronics. However, realizing sophisticated complementary nano-electronics has been challenging due to the p-type nature of carbon nanotubes in air. Fabrication of n-type behavior field effect transistors (FETs) based on assembled aligned CNT arrays is needed for advanced CNT electronics. Here in this paper, we report a scalable process to make n-type behavior FETs based on assembled aligned CNT arrays. Air-stable and high-performance n-type behavior CNT FETs are achieved with high yield by combining the atomic layer deposition dielectric and metal contact engineering. We also systematically studied the contribution of metal contacts and atomic layer deposition passivation in determining the transistor polarity. Based on these experimental results, we report the successful demonstration of complementary metal-oxide-semiconductor inverters with good performance, which paves the way for realizing the promising future of carbon nanotube nano-electronics. [ABSTRACT FROM AUTHOR]

Structural network alignment utilizes the topological structure information to find correspondences between nodes of two networks. Researchers have proposed a line of useful algorithms which usually require a prior mapping of seeds acting as landmark points to align the rest nodes. Several seed-free algorithms are developed to solve the cold-start problem. However, existing approaches suffer high computational cost and low reliability, limiting their applications to large-scale network alignment. Moreover, there is a lack of useful metrics to quantify the credibility of seed mappings. To address these issues, we propose a credible seed identification framework and develop a metric to assess the reliability of a mapping. To tackle the cold-start problem, we employ graph embedding techniques to represent nodes by structural feature vectors in a latent space. We then leverage point set registration algorithms to match nodes algebraically and obtain an initial mapping of nodes. Besides, we propose a heuristic algorithm to improve the credibility of the initial mapping by filtering out mismatched node pairs. To tackle the computational problem in large-scale network alignment, we propose a divide-and-conquer scheme to divide large networks into smaller ones and then match them individually. It significantly improves the recall of mapping results. Finally, we conduct extensive experiments to evaluate the effectiveness and efficiency of our new approach. The results illustrate that the proposed method outperforms the state-of-the-art approaches in terms of both effectiveness and efficiency. [ABSTRACT FROM AUTHOR]

We investigated the types of metabolism and genes involved with N and P reactions, and SOM turnover as well as their interaction was monitored in an apple orchard by metagenome sequencing. The field experiment included plots with and without a cover crop but with weed control, and two subplots with or without chemical fertilizer. The relative abundances of genes involved with N reactions (nirB, nirD, amoB, gltB, and GDH2), P reactions (phoA, pqqC, and E3.1.3.8), and plant degradation were higher in the cover cropped soil after treated with chemical fertilizer compared with the other treatments. The cover crop had a greater effect on the gene network than the chemical fertilizer and it improved the number of links in the network compared with no cover crop. The betweenness centrality scores showed that the genes involved in N and P reactions were important for SOM turnover as well as for N and P reactions. Chemical fertilizer provided more available N and P for SOM turnover in the cover-cropped soil, thereby improving the soil fertility. Finally, the available N and P contents, SOM, and apple yield were increased by the application of chemical fertilizer and cropping with cover plant due to the promotion of interactions among the N and P reactions (as hypothesized by considering abundances of genes involved in both nutrient cycles), and SOM. Our results provide new insights into the interactions between N and P reactions in soil and SOM turnover from the genetic level in an apple orchard with a cover crop and when subjected to chemical fertilization. [ABSTRACT FROM AUTHOR]

Changes in the soil microbial communities and networks were monitored after planting the cover crop for 9 years. The field experiment included plots with a cover crop and without a cover crop but with weed control, and two subplots with or without chemical fertilizer (192 kg N ha−1, 108 kg P2O5 ha−1, and 168 kg K2O ha−1 each year). After applying the cover crop and chemical fertilizer for 9 years, the composition and activity of bacterial and fungal communities changed significantly (p < 0.05), with the cover crop had greater effects than the chemical fertilizer on the composition of the soil microbial community. The relative abundances of 22 selected genera (in Firmicutes and Bacteroidetes) and two selected classes (Ascomycota) related to cover crop residue degradation increased significantly in the presence of the cover crop (p < 0.05). Network analysis showed that the cover crop decreased the number of positive links between bacterial and fungal taxa by 25.33%, and increased the negative links by 22.89%. The positive links among bacterial taxa increased by 16.63% with the cover crop, mainly among Proteobacteria (increase of 39), Firmicutes (16), Actinobacteria (five), and Bacteroidetes (10). The links among fungal taxa were less than among bacterial taxa and were not significantly affected by cover crop. Taxa such as Thaumarchaeota, unidentified_Nitrospiraceae, unidentified_Nitrosomonadaceae, Faecalibacterium, Coprococcus_3, and Ruminococcaceae_NK4A214_group dominated the network without the cover crop but they were not dominant with the cover crop. The relative abundances of potential genes involved with the degradation of cellulose, hemicellulose, and cello-oligosaccharides increased significantly with the cover crop. Therefore, the SOC and TN contents were enhanced by the cover crop with the increase of the soil enzyme activities. Thus, the apple yield was improved by the cover crop. [ABSTRACT FROM AUTHOR]

High concentrations of soluble Mn in electrolytic manganese solid waste (EMSW) in soil cause the severe contamination in China. Calcium oxide and magnesium oxide-dominated stabilizers are suitable for the solidification/stabilization (s/s) of EMSW. However, the long-term performance of s/s using those two types of stabilizer is problematic. The aim of this study was to develop an accelerated aging method to simulate the long-term natural carbonation of solidified/stabilized EMSW. The joint use of accelerated carbonation, leaching test, mineralogical analysis, and microstructural observation was applied to assess the long-term performance of the s/s EMSW system. On an accelerated carbonation test for solidified/stabilized EMSW, an increase in Mn leaching from 13.6 to 408 mg/kg and a 1.5-2.3 decrease in pH was achieved by using CaO-dominated stabilizers, while an increase in manganese (Mn) from 30 to 266 mg/kg and a decrease in pH of 0.17-0.68 was seen using MgO-dominated stabilizers. CaO+NaPO and CaO+CaCO were exceptions in that the leaching value of soluble Mn was lower after carbonation. Mineralogical analysis showed that rhodochrosite in the carbonated s/s system was generated not only from the reduction of hausmannite but also from the reversible reaction between Mn(OH) and MnCO. Carbonation destroyed the tight particle structure resulting in a porous and loose structure. As for s/s EMSW treated by MgO-dominated stabilizers, carbonation affected the agglomerating structure and mineralogical composition by increasing magnesium (Mg) migration, thereby forming hydromagnesite that had weak binding ability and a nested porous shape. Therefore, carbonation by itself does not cause deterioration to s/s products of the soluble Mn but does have significant effects on the microstructure and mineralogical composition. It is recommended to add NaPO or CaCO into a single CaO stabilized EMSW system to prevent aging of the system, allow formation of Mn phosphate precipitates, and improve the absorption and oxidation of soluble Mn(II). [ABSTRACT FROM AUTHOR]

Eight chiral vinylterphenyl monomers, (+)-2,5-bis{4′-[( S)-1″-methylpropyloxy]phenyl}styrene ( Ia), (+)-2,5-bis{4′-[( S)-2″-methylbutyloxy]phenyl}styrene ( Ib), (+)-2,5-bis{4′-[( S)-3″-methylpentyloxy]phenyl}styrene ( Ic), (+)-2,5-bis{4′-[( S)-4″-methylhexyloxy]phenyl}styrene ( Id), (−)-2,5-bis{4′-[( R)-1″-methylpropyloxy]phenyl}styrene ( Ie), (+)-2-{4′-[( S)-1″-methyl-propyloxy]phenyl}-5-{4′-[( R)-1″-methylpropyloxy]phenyl}styrene ( IIa), (−)-2-{4′-[( R)-1″-methylpropyloxy]phenyl}-5-{4′-[( S)-1″-methylpropyloxy]phenyl}styrene ( IIb), and (+)-2-{4′-[( S)-2′′-methylbutyloxy]phenyl}-5-{4′-[( S)-1″-methylpropyl-oxy]phenyl}styrene ( III), were synthesized and radically polymerized. These molecules were designed to further understand long-range chirality transfer in radical polymerization and to possibly tune the chiroptical properties of the polymers by varying the spatial configuration, position, and various combination of the stereogenic centers at the ends of p-terphenyl pendants. The resultant polymers adopted helical conformations with a predominant screw sense. When the stereogenic centers ran away from the terphenyl group as in Ib− d, the corresponding polymers changed the direction of optical rotation in an alternative way and showed no obvious stereomutation upon annealing in tetrahydrofuran. The two stereogenic centers of IIa, IIb, and III acted concertedly in chiral induction, whereas those of Ia and Ie played a counteractive role. The five polymers derived from Ia, Ie, IIa, IIb, and III underwent stereomutation when annealed in tetrahydrofuran. The polymers PIa- e had good thermal stability and high glass transition temperatures ( Ts). They generated liquid crystalline phases at above Ts that could be kept upon cooling, with the exception of PIe. This result was consistent with the extended helical structures. [ABSTRACT FROM AUTHOR]

This paper exhibits good example of high well-defined hollow silica spheres by using a low-cost sodium silicate precursor via a facile method. The N adsorption isotherm shows that this hollow structure leads to a high Brunauer-Emmett-Teller specific area of ca. 217.755 m g. Transmission electron microscopy and scanning electron microscopy images indicate that prepared hollow silica spheres have uniform morphology and narrow size distribution. Particle size analyzer measurement (polydispersity = 0.005; GSD = 1.073) also further confirms the fact that hollow silica spheres with high monodispersity have been successfully developed as expected. [ABSTRACT FROM AUTHOR]

Uranium is a toxic element due to its radioactivity. Developing analytical methods of uranium for avoiding its damage is necessary. In this study, we found that the catalytic effect of mercury(II) on the precipitation reaction of potassium ferrocyanide with potassium ferricyanide could be inhibited strongly by uranium(IV). The sediment produced from the reaction could be deposited on a magnetoelastic foil, resulting in a resonance frequency shift of the foil due to its mass change. The resonance frequency shift of the foil could be wirelessly detected with a detection system. Based on these facts, a wireless magnetoelastic sensing method for the determination of uranium(IV) has been developed based on the inhibitory effect of uranium(IV) on the catalytic precipitation reaction. The influence of manifold variables on the determination was investigated in details. A linear range was found to be 0.9-15.0 μg/L under optimal conditions with a detection limit of 0.46 μg/L. The method offers an opportunity for remote measurement of radioactive samples containing uranium in sealed vessels, which is beneficial to protecting operator health. The method was applied to determine uranium(IV) in real samples with satisfactory results. [ABSTRACT FROM AUTHOR]

The region of Northwest Hebei is an area where Au-Ag polymetallic ore depsits are concentrated in Hebei Province. There were divided the Au ore-concentrated region with the magmatic-metamorphic diamictite zone as the center and the perpheral cover-strata zone and Ag-polymetallic metallogenic zone along the line of Xuanhua-Songli-Chicheng. Research on mantle branch structure indicates that Au-Ag polymetallic ore-forming materials come mainly from the deep interior of the Earth. The ore-forming materials tend to migrate upwards through the multi-stage evolution of mantle plume, and are concentrated as ores in the favourable tectonic expansion zone of a mantle branch structure. As viewed in plane, from the center to the periphery and as viewed in space, from the lower part to the upper part there exists Au-Ag-Pb-Zn zonation, as evidenced by drilling data from a number of mines. So, there is still great potential for ore prospecting in the region of Northwest Hebei. [ABSTRACT FROM AUTHOR]