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In this paper, the plywood obtained from dismantling discarded furniture was selected as pyrolysis experimental materials. Pyrolysis was performed at a heating rate of 100°C/h, 150°C/h and 200°C/h and pyrolysis temperatures of 400°C, 500°C, and 600°C to evaluate the effects of pyrolysis process on products yield and the products features. The results show that the yield of solid products gradually decreases with the increase of pyrolysis temperature and heating rate while liquid products and non-condensing gases' yield gradually increases. The carbon content in solid products reached 80.76 - 94.35%. Carbon content gradually decreases with pyrolysis temperature, but the proportion of C/H and C/N gradually increases. The pyrolysis solution is weakly acidic due to the adhesives in pyrolysis material.

The kagome metal CsV$_{3}$Sb$_{5}$ features an unusual competition between the charge-density-wave (CDW) order and superconductivity. Evidence for time-reversal symmetry breaking (TRSB) inside the CDW phase has been accumulating. Hence, the superconductivity in CsV$_{3}$Sb$_{5}$ emerges from a TRSB normal state, potentially resulting in an exotic superconducting state. To reveal the pairing symmetry, we first investigate the effect of nonmagnetic impurity. Our results show that the superconducting critical temperature is insensitive to disorder, pointing to conventional $s$-wave superconductivity. Moreover, our measurements of the self-field critical current ($I_{c,sf}$), which is related to the London penetration depth, also confirm conventional $s$-wave superconductivity with strong coupling. Finally, we measure $I_{c,sf}$ where the CDW order is removed by pressure and superconductivity emerges from the pristine normal state. Our results show that $s$-wave gap symmetry is retained, providing strong evidence for the presence of conventional $s$-wave superconductivity in CsV$_{3}$Sb$_{5}$ irrespective of the presence of the TRSB, Comment: 8 pages, 4 figures. Nano Letters (in press)

Luoyang No.1 is a Qing Dynasty (1644–1902) inland river ancient wooden shipwreck discovered in September 2013. It adds significantly to the study of Grand Canal transport history and Luoyang’s economic history. The wood characteristics of Luoyang No.1 were investigated in this study using chemical compositions, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nano-indentation (NI), and scanning electron microscopy (SEM). The results showed that the holocellulose content was only 32.84–37.69%, indicating that the cellulose and hemicellulose had been seriously degraded. Based on the XRD pattern, the degree of crystallinity of cellulose in wood ranged from 19.82 to 22.83%. The nano-indentation demonstrated that compared with the undegraded contemporary wood, the elastic modulus and hardness of the ancient ship wood decreased by 45.5% and 32.1%, respectively. Furthermore, the FTIR spectra revealed that the biological deterioration of ancient wood was indicated by a decrease in the peaks related to cellulose and hemicellulose, but the change in lignin was insignificant. The results could provide knowledge for appropriate dewatering, strengthening, restoration strategies and regulation of the museum environment.

Linseed oil and shellac are natural, environmentally friendly materials with good water repellency. They were used to impregnate Chinese ash wood at room temperature (20 °C) using a vacuum-pressure procedure (consisting of three cycles of 0.01 MPa for 1.5 h and atmospheric pressure for 1.5 h) to improve the dimensional stability of wood. The effects of the impregnation treatment on wood color changes, dimensional stability, moisture absorption, and morphological characteristics were evaluated. The linseed oil and shellac treatment improved the dimensional stability of wood. Linseed oil and shellac displayed good permeability in Chinese ash wood, with weight gains of 21.7% and 19.0%, respectively, after impregnation. The swelling coefficients of treated wood in the tangential and radial directions decreased by 15 to 22%, indicating that impregnation improved the dimensional stability of wood. Linseed oil and shellac solidified and occluded the pits within the wood interior to prevent moisture absorption. This method can be used to improve the dimensional stability of a variety of wood products, such as buildings, furniture, and landscape architecture.

Charge density wave (CDW) instability is often found in phase diagrams of superconductors such as cuprates and certain transition-metal dichalcogenides. This proximity to superconductivity triggers the question on whether CDW instability is responsible for the pairing of electrons in these superconductors. However, this issue remains unclear and new systems are desired to provide a better picture. Here, we report the temperature-pressure phase diagram of a recently discovered BiS$_2$ superconductor La$_2$O$_2$Bi$_3$AgS$_6$, which shows a possible CDW transition at $T^*\sim$155 K and a superconducting transition at $T_c\sim$1.0 K at ambient pressure, via electrical resistivity measurements. Upon applying pressure, $T^*$ decreases linearly and extrapolates to 0 K at 3.9 GPa. Meanwhile, $T_c$ is enhanced and reaches maximum value of 4.1 K at 3.1 GPa, forming a superconducting dome in the temperature-pressure phase diagram., 8 pages, 4 figures. This is the first draft of an accepted paper by J. Phys. Condens. Matter

The Huaguangjiao I is an ancient Chinese wooden shipwreck from the South Song Dynasty (AD 1127–1279) discovered in the South China Sea in 1996. The first phase of its conservation, desalination and desulfurization, was completed in 2016. In this paper, three archaeological wood samples exhibiting different degrees of deterioration from Huaguangjiao No. 1 were consolidated with PEG-4000 and dehydrated via freeze drying and supercritical CO2 drying methods. The dimensional stability, hygroscopicity, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used to evaluate the effects of consolidation and dehydration. The results showed that PEG4000 was an efficient consolidation material that also effectively decreased shrinkage during dehydration. Furthermore, both vacuum-freeze and supercritical CO2 drying were efficient methods for treating waterlogged archaeological wood. After PEG4000 impregnation, the shrinkage percentage of the waterlogged archaeological wood became slightly lower than sound wood. The moisture absorption of the experimental specimens ranged within 3.35%–4.53%, and they comprised 50% sound wood, resulting in a marked improvement in dimensional stability. FTIR spectra indicated that impregnation improved wood dimensional stability by reducing hydrophilic groups. These results show that this method can effectively treat waterlogged wood for preservation purposes.

Charge density wave (CDW) instability is often found in phase diagrams of superconductors such as cuprates and certain transition-metal dichalcogenides. This proximity to superconductivity triggers the question on whether CDW instability is responsible for the pairing of electrons in these superconductors. However, this issue remains unclear and new systems are desired to provide a better picture. Here, we report the temperature-pressure phase diagram of a recently discovered BiS

With the continuous expansion of the city, there is a remarkable trend in the diversified form of residential buildings, the fire safety management of residential community is becoming more and more prominent.In this paper, the fire safety management of residential buildings in the downtown area of Chenzhou city is taken as an example for analysis of its weak links, and then the corresponding improvement methods are put forward, so as to make some useful exploration for the improvement of fire safety management of residential buildings in the downtown area of Chenzhou city.

Gold leaf samples of different purities were corroded in a SO2 atmosphere at three different relative humidities (30%, 60%, 90%) at ambient temperature, and the effects on color, gloss, and morphology were studied. Results showed that a corrosion rate of 0.0898 g/cm2 could be attained after 6 weeks at high humidity. Color changes also occurred during the gold leaf corrosion process, and many thin pits formed on the surfaces, as shown by SEM. EDX results showed that these pits contained C, O, and S compounds. By comparing the results of different gold purity samples and different relative humidity conditions, it could be concluded that both gold content and humidity play an important role in SO2 atmosphere corrosion. These conclusions are helpful for the conservation of gold leaf decorative cultural relics.

The emergence of high transition temperature ($T_c$) superconductivity in bulk FeSe under pressure is associated with the tuning of nematicity and magnetism. However, sorting out the relative contributions from magnetic and nematic fluctuations to the enhancement of $T_c$ remains challenging. Here, we design and conduct a series of high-pressure experiments on FeSe thin flakes. We find that, as the thickness decreases, the nematic phase boundary on temperature-pressure phase diagrams remains robust while the magnetic order is significantly weakened. A local maximum of $T_c$ is observed outside the nematic phase region, not far from the extrapolated nematic endpoint in all samples. However, the maximum $T_c$ value is reduced associated with the weakening of magnetism. No high-$T_c$ phase is observed in the thinnest sample. Our results strongly suggest that nematic fluctuations alone can only have a limited effect while magnetic fluctuations are pivotal on the enhancement of $T_c$ in FeSe., Comment: 8 pages, 5 figures. This is the first draft of an accepted paper by Nano Letters

The recent discovery of a nonsaturating linear magnetoresistance in several correlated electron systems near a quantum critical point has revealed an interesting interplay between the linear magnetoresistance and the zero-field linear-in-temperature resistivity. These studies suggest a possible role of quantum criticality on the observed linear magnetoresistance. Here we report our discovery of a nonsaturating, linear magnetoresistance in ${\mathrm{Mo}}_{8}{\mathrm{Ga}}_{41}$, a nearly isotropic strong electron-phonon coupling superconductor with a linear-in-temperature resistivity from the transition temperature to $\ensuremath{\sim}55$ K. The growth of the resistivity in field is comparable to that in temperature, provided that both quantities are measured in the energy unit. Our data sets are remarkably similar to magnetoresistance data of the optimally doped ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$, despite the clearly different crystal and electronic structures, and the apparent absence of quantum critical physics in ${\mathrm{Mo}}_{8}{\mathrm{Ga}}_{41}$. A new empirical scaling formula is developed, which is able to capture the key features of the low-temperature magnetoresistance data of ${\mathrm{Mo}}_{8}{\mathrm{Ga}}_{41}$, as well as the data of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$.

With the emergence of cloud cooperative operation mode, a integration and allocation method of fire support operational resources for cloud cooperative operation mode is proposed to solve the problem of integration and allocation of operational resources in this paper. First, the operational knowledge graph is established to integrate and dynamically manage the operational resources spread across the battlefield. Then a optimization matching method of sub service and operational resources is established for selecting the operational resources that can meet the task requirements. Finally, the simulation results show that this method can solve the problem of integration and allocation of fire support resources in the cloud cooperative operation environment.

Dimensional stability proves to be an important factor affecting the quality of wooden products. As a sort of crude and thermoplastic resin, shellac excreted by lac insects demonstrates water-repellent and environmental-friendly features. The research impregnated shellac with wood at room temperature and with a vacuum-pressure procedure. Efforts were made to examine how shellac treatment affected the dimensional stability, moisture absorption, chemical structure, thermostability, as well as morphological characteristics of wood. Results indicated that shellac treatment was a type of efficient solution useful in the enhancement of the dimensional stability of wood. Shellac solution had good permeability in the wood, and the weight percentage gain reached 13.01% after impregnation. The swelling coefficients of treated wood in the tangential and radial directions decreased by 20.13% and 24.12%, respectively, indicating that impregnation could improve wood dimensional stability. The moisture absorption of shellac-treated wood was reduced by 38.15% under 20 &deg, C and 65% relative humidity. Moreover, shellac treatment significantly modified wood structure, although there were no drastic changes in the spectra. Specimens for shellac treatment ran across two decomposition peaks at 350 and 390 &deg, C, and specimens in the control group saw one more common derivative thermogravimetric curve when the sharp peak approached 355 &deg, C. After impregnation of shellac into wood, the shellac blocked pits and hardened on the intrinsic layer of the wood for fear of hygroscopicity. The practice was applicable to a variety of wood products, such as buildings, furniture, and landscape architecture.

Soil water content (SWC) plays a vital role in the process of evapotranspiration (ET) in rubber plantations. To investigate the influence of the ET process on soil water balance in rubber plantations, we measured SWC at depths of 10, 20, 30, 40, 70, 100, 130 cm, measured the characteristics of root density distribution, and estimated the ET and deep percolation at a rubber plantation in Xishuangbanna using the Hydrus-1D model. Our results indicate the Hydrus-1D model can accurate simulate soil water dynamics in the 0–130 cm of rubber plantations with Nash-Sutcliffe Efficiency Coefficient (NSE) was 0.80–0.96, the Root Mean Squared Error (RMSE) was 0.05–0.02, and the Pearson Correlation Coefficient (R) was 0.82–0.97. Obviously, there were seasonal variation characteristics in soil moisture changes in the rubber plantations of Xishuangbanna. The soil water storage (SWS) dropped to its lowest value of 194 mm and reached its maximum value of 504 mm from the dry season to the rainy season. The simulated ET of the rubber plantation was 1166.1 mm. The large uptake and utilization of soil water by rubber plantations in the dry season affects or exacerbates seasonal drought in Xishuangbanna and leads to a shortage of regional water resources.

Wood vinegar , resulting from the pyrolysis of wood-waste materials, exhibits herbicidal activity against various broadleaf and grass weeds . The objectives of this research were to investigate the composition, property, and efficacy of wood vinegar resulting from the pyrolysis of pruned apple ( Malus × domestica Borkh.) tree branches for control of annual bluegrass ( Poa annua L.). The composition of wood vinegar was analyzed using gas chromatography-mass spectrometry. Water was the major component in wood vinegar and accounted for 85% by weight. Various organic compounds including acids, alcohols, aldehydes, ketones, phenols, esters, nitrides, and carbohydrate were identified but the major organic compound was acetic acid. Treatments were wood vinegar solutions diluted with distilled water at 0%, 6%, 12%, 25%, 50%, and 100% concentrations. By 20 days after treatment (DAT), when foliarly applied at 2800 L ha−1, the lowest concentration of wood vinegar (6%) only caused 23% annual bluegrass injury, while the highest concentration (100%) caused 95% injury; and the concentration of wood vinegar required to induce 50% visual injury (I50) measured 14%. By 20 DAT, when wood vinegar applied to soil at 110 L m−3, the lowest concentration of wood vinegar (6%) caused 26% visual injury, but the highest concentration of wood vinegar (100%) caused 86% visual injury, and I50 measured 21%. In field experiments, the time required to control 50% annual bluegrass measured 13.3 and 6.6 DAT when wood vinegar concentrations at 50% and 100% applied at 2800 L ha−1. Overall, these results indicate that wood vinegar derived from apple tree branches can be used for controlling annual bluegrass.

Pruning trees in urban landscapes produces a large amount of pruning waste. Pyrolysis is a process that thermally converts lignocellulosic biomass to a number of useful products, including wood vinegar. The objectives of this research were to 1) identify the composition and property of wood vinegar resulting from the pyrolysis of elm (Ulmus spp.) tree pruning waste and 2) evaluate the efficacy of wood vinegar for control of several broadleaf weed species. Acids along with various other chemical groups including alcohols, aldehydes, carbohydrates, phenols, nitrides, and ketones were identified in wood vinegar. Water constituted the highest proportion of wood vinegar, accounted for 77 % by weight. In growth chamber experiments, wood vinegar at 4000 L ha−1 showed 95 % injury and 76 % fresh aboveground biomass reduction of perilla mint [Perilla frutescens (L.) Britt.] compared to the nontreated control at 7 d after treatment, whereas a 2000 L ha-1 application volume caused 80 % injury, with 60 % biomass reduction. The efficacy of 1000 or 2000 L ha−1 application volume were significantly lower. In field experiments, wood vinegar showed varying levels of control for perilla mint, creeping woodsorrel (Oxalis corniculata L.), and Carolina geranium (Geranium carolinianum L.). While wood vinegar at 4000 L ha-1 provided 100 % control of perilla mint and control of creeping woodsorrel and Carolina geranium were 82 % at best. Further, faster and greater control was achieved at low temperatures (10 °C) compared with high temperature conditions (20 or 30 °C). Overall, these findings suggest that wood vinegar derived from the pyrolysis of pruning waste can be used as a non-synthetic herbicide for control of broadleaf weeds.

Background Acupressure has been used as an effective way in treating with stomach upset. However the efficacy of acupressure in preventing chemotherapy-induced nausea and vomiting is uncertain. Objective To assess the effectiveness of acupressure on three categories of chemotherapy-induced nausea and vomiting. Data sources Databases had been retrieved from inception through February 2016 for the randomized controlled trials in accordance with the inclusion criteria, including PubMed, Cochrane Central Register of Controlled Trials, Web of Science, EMBASE, Science Direct, CINAHL, China Biology Medicine, Chinese National Knowledge infrastructure, Wan Fang and Database for Chinese Technical Periodicals. Additional studies were identified through hand searches of bibliographies and Internet searches. Design Systematic review with meta-analyses and trial sequential analysis of randomized controlled trials. Review methods Two reviewers selected relevant eligible articles, critical appraisal of the methodological quality was conducted on the basis of using Cochrane Handbook. A standardized Excel form was used to extract information. Meta-analysis and trial sequential analysis was performed using software RevMan 5.3 and TSA 0.9. Results Twelve studies with 1419 patients were included. Only three studies were assessed as high quality, one study was evaluated as moderate, and eight studies were evaluated as poor. The meta-analysis showed that acupressure reduced the severity of acute (SMD=−0.18, 95% CI −0.31 to −0.05, p p =0.04) nausea. However, there was no benefit effect on the incidence or frequency of vomiting. No definitive conclusions were drawn from the trial sequential analysis. Conclusion This systematic review suggested a protective effect of acupressure on chemotherapy-induced nausea and vomiting, while more well-designed clinical trials with larger sample size were needed to draw a definitive conclusion.

Cytoskeletal reorganization is essential to keratinocyte function. Rac1 regulates cytoskeletal reorganization through signaling pathways such as the cofilin cascade. Cofilin severs actin filaments after activation by dephosphorylation. Rac1 was knocked out in mouse keratinocytes and it was found that actin filaments disassembled. In the epidermis of mice in which Rac1 was knocked out only in keratinocytes, cofilin phosphorylation was aberrantly elevated, corresponding to repression of the phosphatase slingshot1 (SSH1). These effects were independent of the signaling pathways for p21-activated kinase/LIM kinase (Pak/LIMK), protein kinase C, or protein kinase D or generation of reactive oxygen species. Similarly, when actin polymerization was specifically inhibited or Rac1 was knocked down, cofilin phosphorylation was enhanced and SSH1 was repressed. Repression of SSH1 partially blocked actin depolymerization induced by Rac1 depletion. Therefore, aberrant cofilin phosphorylation that induces actin polymerization might be a consequence of actin disassembly induced by the absence of Rac1.

The environmental impact assessment (EIA) of cascade dams building in international rivers has been widely discussed in China and ASEAN countries since the 1990s. In Southwest China, all the great mountainous rivers have been the major state base for large-scale hydropower development. Among these rivers, the environmental change and response of the watercourse under the cascade dams building in the upper Mekong (called Lancang River in China) has been the focus in recent 20 years. In this paper, the Lancang River, which has over 25 years of large-scale hydropower development, was chosen as a case study for establishing the affected evaluation indicators system and its regression model of runoff and sediment, determining the indicators weight by the hierarchy analysis method and factor analysis method, and setting up the quantitative evaluation models of indicators affected level based on the “marginal efficiency” principle. Using these methods and model established, the influence degree of runoff and sediment in the Lancang River from 1986 to 2007 were assessed. The major results are: (1) the impact of sediment transport change by the cascade development is much higher than that of the runoff change; (2) the years’ number with different impact levels respectively are 72.7% as the “smallest” level, 18.2% as “smaller”, and 9.1% as “general”; (3) the change process of runoff and sediment shows a “U-shaped” pattern, which indicates the balance of sediment change because of the interaction of sediment reduction by Manwan reservoir storage and the increase by the Dachaoshan dam construction.

Due to a humid climate, karst areas in south China have an abundance of groundwater. With the development of agriculture, industry, and mining, the potential factors that may result in catastrophic groundwater pollutions are increasing. A phosphorus groundwater pollution event and its subsequent emergency treatment at Penshuidong Cave in Songming, Yunnan Province on February 24, 2008 were analyzed in addition to water quality monitoring in the region. The results showed that concentrations of phosphates, fluoride, cyanides and volatile phenols in phosphorus sludge waste liquid to be 11,532, 252, 224, 200 times higher than that of the Environmental quality standards for surface water (GB 3838-2002) III, respectively. The element phosphorus concentration was 16,510 times higher than the limit set by the Water quality standard for fisheries (GB11607-1989). The addition of quicklime and water to the phosphorus sludge waste liquid dumping pit clearly decreased pollutant concentrations, which indicates that the quicklime can remove the phosphorus from the waste liquid. Peak values of pollutant concentration decreased along the flow direction, which suggests the highly concentrated polluted water mass may be diluted during its movement. After treatment with water, a pollutant concentration peak appears at the groundwater outlet indicating that washing may accelerate the moving speed of the pollutants in groundwater. Element phosphorus concentrations, however, remained at a high and stable range(46–65 times higher than the limit set by the Water quality standard for fisheries).

Cytoskeletal reorganization is essential to keratinocyte function. Rac1 regulates cytoskeletal reorganization through signaling pathways such as the cofilin cascade. Cofilin severs actin filaments after activation by dephosphorylation. Rac1 was knocked out in mouse keratinocytes and it was found that actin filaments disassembled. In the epidermis of mice in which Rac1 was knocked out only in keratinocytes, cofilin phosphorylation was aberrantly elevated, corresponding to repression of the phosphatase slingshot1 (SSH1). These effects were independent of the signaling pathways for p21-activated kinase/LIM kinase (Pak/LIMK), protein kinase C, or protein kinase D or generation of reactive oxygen species. Similarly, when actin polymerization was specifically inhibited or Rac1 was knocked down, cofilin phosphorylation was enhanced and SSH1 was repressed. Repression of SSH1 partially blocked actin depolymerization induced by Rac1 depletion. Therefore, aberrant cofilin phosphorylation that induces actin polymerization might be a consequence of actin disassembly induced by the absence of Rac1.

Reinvestigation of the n-BuOH extract of the roots of Clematis argentilucida led to the isolation of a new ursane-type triterpenoid saponin 1 and a new taraxerane-type saponin 2, four known saponins 3–6 first isolated from the species, together with seven saponins 7–13 reported in the previous papers. The structures of saponins 1–6 were elucidated by extensive spectroscopic analysis and chemical evidences. The ursane-type and taraxerane-type triterpenoid saponins were obtained from genus Clematis for the first time, and the aglycone of saponin 1, 3β,28-dihydroxy-18αH-ursan-20-en was first encountered. The cytotoxicity of all the saponins was evaluated against human glioblastoma U251MG cell lines. The monodesmosidic saponins 1, 2 and 4–8 exhibited cytotoxic activity against the cells with IC50 values ranging from 6.95 to 38.51 μM.

Due to the climate change, human activities and other factors, there are some inter-annual or inner-annual alterations happened in the hydrological series. Many important works had been affected severely, such as the planning and designation of hydraulic engineering, the sustainable utilization and optimal allocation of water resources etc. However, the studies about the features of inner-annual hydrologic elements distribution are mainly focused on the analysis of the inhomogeneity, with the disadvantage of unintuition and the poor comparability of the indicators from the view of methods that used nowadays, few of the studies considering the alteration of the inhomogeneity happened or not under the changing environment. Therefore, the Gini Coefficient with the advantage of well description of inhomogeneity is used to set up the analysis method of hydrological alteration of the inner-annual distribution. In this method, the series of homogeneity of inner-annual hydrological elements distribution will be calculated first of all, then the Hydrological Alteration Diagnosis System is used to analyze whether the alteration is happened in the series or not, finally, the mean difference method will be employed to analyze the attributions if the alteration is existing. At the end of this study, with the monthly runoff data from the year of 1954 to 2005 of Longchuan Station at Dongjiang River, the alterational characteristics of inner-annual runoff distribution is calculated and the attribution analysis is conducted in succession. The results show that: at the year of 1973, the increasing jump alteration happened in the series of inner-annual runoff distribution, which means the tendency of inner-annual runoff distribution becomes equalization. About 60% of the alteration is induced by the human activities, especially the construction and operation of Fengshuba Reservoir, and the factor of climate change only accounts for about 40%.