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In order to investigate the shear strength of fine sand reinforced by grouting and freezing method, a series of direct shear tests was carried out in a temperature-adjusted wall-in refrigerator. Four different soil samples were prepared including non-grouted unfrozen sample (NU), grouted unfrozen sample (GU), non-grouted frozen sample (NF), and grouted frozen sample (GF) considering different factors of moisture content, water–cement ratio, freezing temperature, and curing time. The linear Mohr–Coulomb strength envelope was adopted to describe the relationship between shear strength and vertical pressure of fine sand. The function of freezing and grouting was validated, and the main results show that the shear strength of unfrozen sample decreases with increasing moisture content; in terms of frozen sample, the shear strength increases with moisture content and decreasing freezing temperature; a greater water–cement ratio always produces larger shear strength of GF sample which also increases with curing time as expected; however, the strength of GU sample experiences an opposite trend in water–cement ratio; the effect of different factors on the cohesion cand internal friction angle φwas also discussed and analyzed with many proposed non-linear models.

ABSTRACTExponential fertilization has been regarded as an important technique for improving seedling growth and enlarging internal nutrients reserve. However, the effects of exponential fertilization under varying fertilization levels on seedlings’ growth, nutritional status, and nonstructural carbohydrates (NSC) are poorly understood. We employed Armand pine (Pinus armandii) seedlings to investigate the responses of growth, nutrients (nitrogen, phosphorus, and potassium) in seedlings, and NSC in organs to varying exponential and conventional fertilization levels. Shoot height, root collar diameter, and biomass increased and then declined with the increased fertilization levels. At high fertilization levels (≥300 mg seedling−1), the seedings accumulated more biomass in exponential fertilization than in conventional fertilization. The exponentially fertilized seedlings contained more concentrated nitrogen, starch, and NSC than the conventionally fertilized ones. Vector analysis revealed that conventional fertilization of 200 mg seedling−1or exponential fertilization of 300 mg seedling−1could induce luxury consumption. NSC was closely related to the nutrient states. With the increased fertilization level, regardless of the regime, soluble sugar concentrations in roots and needles trended toward declining with changes in the nutrient supply from deficiency to sufficiency and then increased with the changes from sufficiency to toxicity. Meanwhile, starch and NSC concentrations in roots and needles increased with the changes in the nutrient supply from deficiency to sufficiency; the concentrations in roots decreased with the changes from sufficiency to excess. Exponential fertilization at high levels did not only promote seedling growth but also induced seedlings to reserve more nutrients and NSC, which could improve afforestation success.

Research results show that comparing to unfrozen soil, frozen soil has more complicated deformation behavior owing to the presence of ice. On the basis of triaxial tests results of frozen silty clay (FSC) at ˗6 °C, due to the ice cementation, the critical state line (CSL) of FSC does not cross the origin of the deviatoric plane. The critical deviatoric stress of FSC increases nonlinearly as the mean stress growing; however, further increases of the mean stress give rise to the decreases in the critical deviatoric stress. Because under high mean stresses, the ice-melting and-crushing (IMAC) cause ice cementation degradation. To predict the deformation of FSC, a new anisotropic constitutive model that considers the degradation of ice cementation is proposed. In the proposed model, first, the elastic parameters of FSC are obtained by conducting triaxial shear loading-unloading (TSLU) tests and isotropic compression loading-unloading (ICLU) tests. Second, yield and plastic potential functions are proposed, the two involve the modified mean stress and indicate the degradation of ice cementation. Third, a double hardening law pertaining to isotropic hardening and rotational hardening is developed by considering initial anisotropy and stress-induced particle rotation under shear loading. Finally, the comparison results confirm that the developed constitutive model is valid and suitable for describing the stress–strain relations of FSC.

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Permafrost is widely distributed in China and around the world. In permafrost regions, soil frost heave and thawing are severe and frequent, and can destabilize pile foundations. To this end, a finite element model of a single pile in frozen soil is established to investigate the frost heave and frost jacking response to ensure its safety in the Qinghai-Tibet Plateau. Firstly, a hydro-thermal coupling model of a single pile in frozen soil is established based on coupling parameters and initial and boundary conditions. Then the temperature and moisture distributions are analyzed through the established coupling model. A hydro-thermo-mechanical coupling model is developed by importing the ice content and temperature results. Simulation results indicate that the amount of frost heave is greater at locations closer to the ground surface, and the displacement is smaller for frozen soil that is closer to the side of the pile. The results on frost jacking behavior of piles from this study can serve as a reference for the design, construction and maintenance of foundations.

The growing appreciation of immune cell–cell interactions within disease environments has led to extensive efforts to develop immunotherapies. However, characterizing complex cell–cell interfaces in high resolution remains challenging. Thus, technologies leveraging therapeutic-based modalities to profile intercellular environments offer opportunities to study cell–cell interactions with molecular-level insight. We introduce photocatalytic cell tagging (PhoTag) for interrogating cell–cell interactions using single-domain antibodies (VHHs) conjugated to photoactivatable flavin-based cofactors. Following irradiation with visible light, the flavin photocatalyst generates phenoxy radical tags for targeted labeling. Using this technology, we demonstrate selective synaptic labeling across the PD-1/PD-L1 axis in antigen-presenting cell–T cell systems. In combination with multiomics single-cell sequencing, we monitored interactions between peripheral blood mononuclear cells and Raji PD-L1 B cells, revealing differences in transient interactions with specific T cell subtypes. The utility of PhoTag in capturing cell–cell interactions will enable detailed profiling of intercellular communication across different biological systems.

To ascertain the possibility of cultivating maize using biological nitrogen fixation (BNF) by leguminous green manure crops in maize/leguminous green manure intercropping systems, BNF and nitrogen (N) transfer were studied in Xining and Wuwei, two typical northwestern Chinese cities. The experimental treatments included monocultured maize, monocultured green manures (hairy vetch and common vetch), and their intercropping systems. The proportions of N derived from the atmosphere (%Ndfa) in intercropping systems were not significantly different from that in monocultured green manure systems at either experimental site, except for that in hairy vetch (HV) in Xining. The amount of N derived from the atmosphere (Ndfa) of common vetch (CV) significantly decreased from 1.16 and 1.10 g/pot in monoculture to 0.77 and 0.55 g/pot when intercropped with maize, in Xining and Wuwei, respectively, and the Ndfaof HV when intercropped significantly decreased from 1.02 to 0.48 g/pot in Xining. In the intercropping systems in Xining and Wuwei, the amounts of N transferred (Ntransfer) from CV to maize were 21.54 and 26.81 mg/pot, accounting for 32.9 and 5.9% respectively of the N accumulation in maize, and the values of Ntransferfrom HV to maize were 39.61 and 46.22 mg/pot, accounting for 37.0 and 23.3%, respectively, of the N accumulation in maize. Path analysis showed that soil nutrient and green manure biomass were mainly related to Ndfa, and that δ15N had a primary relationship with Ntransfer. We found that 5.9–37.0% of N accumulation in maize was transferred from green manures, and that the N transfer ability to maize of HV was higher than that of CV. In conclusion, intercropping with leguminous green manures provided a feasible way for maize to effectively utilize biologically fixed N.

Idiopathic nephrotic syndrome is the most common glomerular disease in children, but there are still some difficulties in treating childhood steroid-dependent or steroid-resistant nephrotic syndrome (SDNS/SRNS). Rituximab (RTX) might be an effective and safe choice.

A three-component reaction has been developed for the construction of multiaryl-substituted pyrrole derivatives from arylketones, amines, and nitrovinylarenes under metal-free conditions. Hence, homologous 1,2,4-triaryl-substituted pyrrole products were obtained in good to high yields. Furthermore, 2,3,5-triaryl-substituted pyrroles were selectively formed in the absence of nitrovinylarenes. The photophysical properties of some pyrrole products have been investigated to show good aggregation-induced emission (AIE) activity.

We investigated the dynamic dispersion stability of GO with metal ions and observed a redispersion behavior in concentrated Fe3+solution, other than permanent aggregation. The exchange with Fe3+ions drives the reversion of zeta potential and enables the redispersion to individual GO-Fe3+complex sheets, following a dynamic electric double layer mechanism.

A direct and facile construction of optically pure julolidine derivatives through ruthenium-catalyzed enantioselective cascade hydrogenation and reductive amination of 2-(quinolin-8-yl)ethyl ketones has been developed. By means of this protocol, various chiral julolidine compounds were obtained in high isolated yields (up to 94%) with excellent diastereoselectivities (up to >20:1 dr) and enantioselectivities (up to 99% ee) under mild conditions. Furthermore, the synthetic practicality of this protocol was illustrated by the preparation of hexahydrojulolidines and a chiral fluorescent molecular rotor.

Lactobacillus kefiralcohol dehydrogenase (LkADH) and ketoreductase from Chryseobacterium sp. CA49 (ChKRED12) exhibit different chemoselectivity and stereoselectivity toward a substrate with both keto and aldehyde carbonyl groups. LkADH selectively reduces the keto carbonyl group while retaining the aldehyde carbonyl group, producing optically pure R-alcohols. In contrast, ChKRED12 selectively reduces the aldehyde group and exhibits low reactivity toward ketone carbonyls. This study investigated the structural basis for these differences and the role of specific residues in the active site. Molecular dynamics (MD) simulations and quantum chemical calculations were used to investigate the interactions between the substrate and the enzymes and the essential cause of this phenomenon. The present study has revealed that LkADH and ChKRED12 exhibit significant differences in the structure of their respective active pockets, which is a crucial determinant of their distinct chemoselectivity toward the same substrate. Moreover, residues N89, N113, and E144 within LkADH as well as Q151 and D190 within ChKRED12 have been identified as key contributors to substrate stabilization within the active pocket through electrostatic interactions and van der Waals forces, followed by hydride transfer utilizing the coenzyme NADPH. Furthermore, the enantioselectivity mechanism of LkADH has been elucidated using quantum chemical methods. Overall, these findings not only provide fundamental insights into the underlying reasons for the observed differences in selectivity but also offer a detailed mechanistic understanding of the catalytic reaction.

Byline: Dan Weil and Ellen Chang Alan Greenspan, accused of being overly optimistic when he was Federal Reserve Chairman during from 1987 through 2006, is bullish on America again.He sees [...]

Container sea-rail transport is increasingly becoming a mainstream mode of transport. It is an effective way to improve the transport efficiency by integrating the business processes of container sea-rail combined transport. According to analyse the business processes of container sea-rail combined transport, this paper designs the integration framework based on four levels: the base layer, the integration layer, the information transfer layer and the information presentation layer. Arena is used to simulate the process. The simulation results show that the freight transportation cycle of the railway transportation, ocean transportation and container sea-rail combined transport is reduced. Therefore, it is feasible and necessary to integrate the business process of container sea-rail combined transport.

Plenty of biological materials are constructed from repeated unit cells with handed configurations, wherein the hierarchical self-assembly of handed units confers optimized mechanical properties and environmental adaptability to bulk biological materials. Inspired by biological handed architectures, we propose handedness-controlled and solvent-driven actuators by programming twisted fibers, such as twisted graphene oxide fibers (TGFs), with mirrored handedness, mechanical robustness and superb flexibility. The large twists (beyond 4800 turns per meter), hair-like diameter (down to 63 μm), large tensile strain (29%) and light weight (1.49 g cm−3) of TGFs enable them to provide a large start-up torque of 2.7 × 10−7N m, and to deliver a record rotor kinetic power of 89.3 W kg−1when stimulated by polar solvents such as acetone and water. By assembling handed TGF units, we achieve precise outputting of rotor kinetic energy (from 0.78 W kg−1to 12.5 W kg−1), controllable harvesting of electrical energy (from 2.37 W kg−1to 11.5 W kg−1), and free handling of a heavy object. The activeness, inertness and operation of all the actuating systems are well controlled by the handedness of TGF units. They are highly stable and reversible, and maintain a high energy output efficiency over multiple operation cycles. These handedness-controlled systems are also extended to hybrid twisted fibers containing nanocomposites and polymers, indicating their general practicability. Handedness-controlled actuators open an alternative avenue for fabricating energy harvesters, responsive textiles, electronic skins and soft robots.

An efficient synthesis of pyrroles and indoles has been developed via three-component ordered annulation of amines, ketones, and nitrovinylarenes. The reaction selectivity can be well controlled under metal-free conditions to afford the corresponding heterocyclic products in good yields.

Carbon textiles are promising electrode materials for wearable energy storage devices owing to their conductive, flexible, and lightweight features. However, there still lacks a perfect choice for high-performance carbon textile electrodes with sufficient electrochemical activity. Graphene fiber fabrics (GFFs) are newly discovered carbon textiles, exhibiting various attractive properties, especially a large variability on the microstructure. Here we report the fabrication of hierarchical GFFs with significantly enlarged specific surface area using a hydrothermal activation strategy. By carefully optimize the activation process, the hydrothermally activated graphene fiber fabrics (HAGFFs) could achieve an areal capacitance of 1060 mF cm–2in a very thin thickness (150 μm) and the capacitance is easily magnified by overlaying several layers of HAGFFs, even up to a record value of 7398 mF cm–2. Meanwhile, a good rate capability and a long cycle life are also attained. As compared with other carbon textiles, including the commercial carbon fiber cloths, our HAGFFs present much better capacitive performance. Therefore, the mechanically stable, flexible, conductive, and highly active HAGFFs have provided an option for high-performance textile electrodes.

Aiming at defects of traditional mobile commerce process, grid management thoughts are applied in its optimization. Grid mobile commerce process measure model is put forward on the basis of mobile commerce process which studying from users' point and according to DIT (the Distance of Information-state Transition). Shopping online by mobile phone has been done in ways of traditional mobile commerce process and grid mobile commerce process respectively according to usual shopping on-line habits. Those two shopping' DIT values are measured and results are compared based on DIT theory. In conclusion, the measurement method provides a quantitative analysis thought on grid mobile commerce process, meanwhile, comparison results show that grid mobile commerce process constructed is superior to traditional mobile commerce process from a user's experience point of view.

Dissimilatory Fe(III) reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe(II) species accumulation could indicate the reduction ability. The effects of different green manures on Fe(III) reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch (RRV), rice-rice-rape (RRP), rice-rice-rye-grass (RRG) and rice-rice-winter fallow (RRF). Soils were sampled at flowering stage of milk vetch and rape (S1), before transplantation (S2), at tillering (S3), jointing (S4), and mature (S5) stages of the early rice, and after the harvest of the late rice (S6). The contents of TFeHCl(HCl-extractable total Fe), Fe(II)HCl(HCl-extractable Fe(II) species) and Fe(III)HCl(HCl-extractable Fe(III) species) were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe(II)HClaccumulation were investigated. The results showed that TFeHClin RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe(II)HClincreased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe(II)HClin RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe(III)HClshowed oppositely, and Fe(II)HCl/Fe(III)HClperformed similarly to Fe(II)HCl. The maximum accumulation potential of Fe(II)HClwas significantly higher in RRF, while the highest maximum reaction rate of Fe(II)HClaccumulation appeared in RRG. Significant correlations were found between the indexes of Fe(II)HClaccumulation and soil pH, oxidation-reduction potential (Eh) and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHClin red paddy soils, but promoted the ability of Fe(III) reduction, especially the ryegrass; Fe(II)HClincreased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.

In 2021, The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results. First, a series of versatile organoboron catalysts were synthesized for ring-opening (co)polymerizations. Second, a catalyst-free polycondensation mechanism was proposed for the production of polyesters with high molecular weights. Third, a co-assembly method that can fabricate films and coatings with controllable structures and properties on various substrates was demonstrated, providing a platform for the construction of novel surface coatings. Forth, facile methods for producing high-productivity poly(propylene carbonate) and semicrystalline polyester have been discovered. And linear non-conjugated polyesters exhibiting yellow-green clusteroluminescence were developed for the first time. Fifth, a supramolecular prodrug nano-assembly strategy has been developed for reactive nitrogen species potentiated chemotherapy. Sixth, a series of tough and stiff supramolecular hydrogels with shape memory properties have been used for information encryption. Seventh, reversible fusion and fission of wet-spun graphene oxide fibers has been successfully achieved. Eighth, three non-conjugated polypeptides were synthesized and the mechanism of clusteroluminescence was studied. Ninth, a series of conducting covalent organic frameworks with high electrical conductivity and carrier mobility have been used as high-performance chemiresistor, electrocatalyst, and organic field-effect transistor. Tenth, the exploration of non-fused electron acceptors, and their photostable mechanism are exemplified for developing high-performance, low-cost and eco-friendly polymer solar cells. Finally, gel-grown long-range ordering bulk-heterojunctions has achieved improved X-ray detector performance.

Development of detection platforms having portable, easy-to-use, and cost-effective designs is essential for environmental monitoring as well as food safety inspection. Herein, we proposed a smartphone-based handheld sensing strategy integrated with nitrogen-doped carbon dots (NCDs) test strip by employing three-dimensional (3D) printing technology for visual detection of Hg2+. Using this handheld detection platform, the FL color of test strips varied from red to purple with the increase of Hg2+concentration. A great linear response between the R/B value and Hg2+concentration in the range of 0 μM− 125 μM was shown, with a detection limit of 0.024 μM. Further, the constructed platform was applied for quantitative detection of Hg2+in real water samples. Interestingly, as-prepared NCDs allowed the monitoring of Hg2+with the dual-signal ratiometric model. Finally, the NCDs were used to detect Hg2+in biological systems with satisfactory results. This work will contribute to the new strategy to design easy-to-use and user-friendly devices for on-site quantitation of targets.

A solvent-free thermoplastic forming processing of graphene materials is invented by polymer intercalation from graphene oxide precursor.The correlation between interlayer spacing and thermoplastic forming capability of polymer-intercalated graphene oxide solid is uncovered.The multi-scale forming of graphene materials from Gaussian curved shapes to surface relief patterns with size precision down to 360 nm is realized.

Monodomain liquid crystals of graphene oxide over 30 cm is realized by boundary-free sheargraphy.The achieved monodomain liquid crystals have bidirectional sheet ordering, exhibiting unique optical, rheological, and conductive properties.Boundary-free sheargraphy extends to freely design delicate topology of two-dimensional colloids, including topological structures with defect strength from − 2 to + 2 and complex polydomain.

On the basis of a long-term (30 years) field experiment that involved four rotation systems, rice-rice-winter fallow (RRF), rice-rice-ryegrass (RRG), rice-rice-rape (RRP), and rice-rice-milk vetch (RRV), this study described the effects of green manure on the microbial communities in the red paddy soils using 454 pyrosequencing for the 16S rRNA gene. The Chao1 richness and non-parametric Shannon's index increased in all soil samples that received green manure treatments. The communities’ structures with the green manure applications were significantly dissimilar from that under the winter fallow. Using Metastats tests, many genera in the RRG, RRP and RRV soils were significantly different from those in the RRF soil, including a number of genera that functioned in the nitrogen and sulfur cycles. Analyses of the genera with these functions revealed the shifts in microbial ecosystem functions after long-term green manuring. Changes in the microbial communities increased the ammonium supply and decreased the soil acidification in green-manure-amended soils. Together, these data suggested powerful effects of green manure on both the microbial communities and the biogeochemical cycle driven by the shifts in bacterial functional groups.

To research and analyze the additional stress distribution and change of granular materials, the model tests are used to observe vertical additional stress in different position and depth in different foundations. And the comparison between observed values both in different soils and single soils is conducted to analyze the transmission and attenuation of additional stress in granular materials. The research results show that the existing of boundary surface can lead to different vertical additional stress transmit obviously. And with the increasing of loading, the vertical additional stress differences between that of different soils get larger, meanwhile, the ratio of stress differences to smaller additional stress increases slightly. With the increasing of depth, the attenuation rate of vertical additional stress of silty soil changes much fast than that of fine sand. Wherever in horizontal direction or vertical direction, the vertical additional stress of fine sand which has higher compression modulus in different soils is slightly larger than that in single soil and transfers additional stress (loading) more under the same loading. To granular materials, inner friction structure effect is evident influence to additional stress transfer.

To research and analyze the additional stress distribution and change of granular materials, the model tests are used to observe vertical additional stress in different position and depth. And the comparison between observed values and theoretical values is conducted to analyze the transmission and attenuation of additional stress in granular materials. The research results show that calculated values are based on Boussinesq solution which ignores the property of soil layer (materials), the distribution of additional stress for fine sand which belongs to granular materials is largely deviated from theoretical value. For granular materials, inner friction structure effect is evident influence to additional stress transfer. And continue using calculation method which is based on continuum materials will have bigger difference and even wrong.

With the rapid development and the wide use of mobile technology, m-commerce research has gradually become the focus of scholars. Difficulties exist in m-commerce, such as information sharing, business collaboration, and process reengineering. Grid management, a new managerial concept, has the potential of being a powerful weapon that affects the study on m-commerce process. This study systematically analyzes the traditional m-commerce process and its problems. On that basis, this paper constructs the grid m-commerce process based on the idea of grid management. Through the help of Arena simulation software, the authors prove that all the convenience, function, and safety of the process are improved by grid M-commerce process.

To research and analyze the neutral point distribution of rigid pile composite foundation on collapsible loess ground in high speed railway, the centrifuge model tests are used to imitate pile raft composite foundation and pile net composite foundation in different pile spacing based on the experimental study at home and abroad. The research results show that the movement of negative skin friction and the position of neutral point which is drop conspicuously with larger pile spacing are a continuous changing process in composite foundation. In the pile spacing 2D,4D,6D of pile raft composite foundation, the stable range of neutral point position are 0.25(the pile length ratio), 0.59,0.63 separately in post-construction stage. In the pile spacing 2D(no pile-cap),4D(no pile-cap),4D(pile-cap),6D(pile-cap) of pile net composite foundation, the stable range of neutral point position are 0.37to0.43(the pile length ratio),0.50,0.80,0.81separately in post-construction stage. The pile-cap setting has more influence on Neutral point distribution. Suggestions are given that the waterproof and drainage measures in foundation must be considered when setting up composite foundation on collapsible loess.

The long-term safety of consuming low-carbohydrate diets (LCDs) remains controversial. As high protein and high fat might accelerate chronic kidney disease (CKD) progression, the impact of LCD on mortality might be different in subjects with CKD and subjects without CKD. Therefore, the objective of this study was to assess the association of LCD with mortality among individuals with and without CKD.

Performance of simultaneous removal of SO2 and NO from the simulated thermal power plants gas using piperazine-urea-triethylene diamine ternary system absorbent was investigated in this paper. Furthermore, the influences of the concentration of triethylene diamine, pH value, the absorption temperature and the total inlet flow rate of the simulated gas on simultaneous absorption behavior were discussed by means of the removal efficiency of SO2 and NO. A better simultaneous desulfurization and denitration behavior could be obtained under the absorption condition of triethylene diamine concentration of 0.3 mol/L, pH value of 6, inlet simulated gas flow rate of 500 ml/min, and the absorption temperature of 40 degC. Under the above absorption condition, the simultaneous NO removal efficiency of 70.28% and SO2 removal efficiency of 99.30% could be obtained.

DNA sequences extracted from preserved remains can add considerable resolution to inference of past population dynamics. For example, coalescent-based methods have been used to correlate declines in some arctic megafauna populations with habitat fragmentation during the last ice age. These methods, however, often fail to detect population declines preceding extinction, most likely owing to a combination of sparse sampling, uninformative genetic markers, and models that cannot account for the increasingly structured nature of populations as habitats decline. As ancient DNA research expands to include full-genome analyses, these data will provide greater resolution of the genomic consequences of environmental change and the genetic signatures of extinction.