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The crop root system is pivotal for water and nutrient uptake. Although the breeding selection significantly increased the yield of modern wheat cultivars, then how this selection reshapes the root system remains largely unknown. Here we performed a large-scale transcriptomic and phenotypical investigations on the seedling root of 406 wheat accessions, which demonstrated modern cultivars (MC) had significantly changed in the root transcriptome and root development. The MC had a significantly larger seedling root system than that in landraces (LA), and this was mainly due to theRht-D1ballele introduction. Physiological and cytological investigations showed that theRht-D1bsuppressed gibberellin (GA) signaling, thus inhibiting the cell length in above-ground tissue but increasing the cell length in roots. This distinct regulation of GA signaling between above- and under-ground tissues contributed to MC having a significantly larger root-shoot ratio. Moreover,Rht-D1balso has a GA-independent role to enlarge root cell width that enhanced the root diameter, ultimately contribute to a larger root surface and volume to MC seedlings. These findings provide new insights to understand the successful application of GA-suppressing alleles in modern wheat breeding and its futural application to form a robust wheat root system.Short SummaryRht-D1bis the major allele that contribute a larger root system and higher root-shoot ratio to modern wheat cultivars.

The remaining waste residues of crops such as straws are considered a sustainable material that can be used in the manufacture of medium-density fiberboards (MDF). The hybrid Pennisetum straw has a high cellulose content, which gives it the potential to be used as a sustainable material in the manufacturing of MDF. In this study, a hot-pressing method was used to obtain MDF with a density of 650 kg m−3 and a thickness of 15 mm from hybrid Pennisetum straws. The effect of pressing temperatures on the thermal stability and physical properties of the obtained MDF was discussed. The results showed that the MDF obtained by hot pressing at 195 °C for 7.5 min had the optimum physical properties, which contained a static bending strength of 12.33 MPa, a nail holding force of 1313 N, and an elastic modulus of 2572 MPa. The mechanism of interfacial adhesion between fiber and resin was investigated. It was found that increasing the pressing temperature not only promoted the curing of the urea–formaldehyde resin, but also promoted the degradation of hemicellulose and lignin inside the straws.

Recycling silicon from environmentally hazardous diamond wire saw silicon powder waste (DWSSP) and effectively removing boron is still an elusive aim. Here, pressure-less sintering and dynamic-slag...

Methyltriethoxysilane based aerogel monoliths with excellent mechanical properties, an ultra-low density, and a highly efficient thermal insulating property were prepared by an improved simple and environmental-friendly ambient pressure drying process. The morphology, particle size, and nano-pore volume of aerogel monoliths were characterized by scanning electron microscope and nitrogen gas adsorption-desorption analyzer. The elastic modulus of particles in aerogel monoliths and the compressive stress-strain response of aerogel monoliths were estimated based upon experimental data obtained via atomic force microscope and materials testing machine. A structural model is proposed to estimate the critical compressive stress with a structural coefficient being introduced to manifest the microstructural integrity of aerogel monoliths. The mechanism for the low bulk density aerogel monoliths to exhibit a linear stress-strain response and a non-buckling failure mode under the uniaxial compression is discussed.

Intestinal probiotics are a primary focus area of current medical research. Probiotics such as bifidobacteria and lactobacilli can positively impact obesity and other metabolic diseases by directly or indirectly affecting lipid metabolism. However, the precise mechanisms of these effects remain unclear. In our previous work, the novel strain Lactobacillus reuteri HI120 was isolated and identified. HI120 expresses high levels of linoleic isomerase, resulting in the production of large amounts of conjugated linoleic acid (CLA) when mixed with linoleic acid (LA). As HI120 can efficiently transform LA into CLA, the effect of HI120 on the lipid metabolism in C57BL/6 obese mice was studied and the underlying molecular mechanism was explored in vitro. The results revealed no significant change in the diet, body weight, and serum triglyceride levels in mice. However, serum cholesterol levels were significantly decreased. The underlying mechanism may involve a CLA-mediated reduction in the gene expression levels of NPC1L1, SREBP-2, and HMG-CR, resulting in reduced cholesterol synthesis and absorption. Thus, HI120 can be developed as a potential probiotic formulation. After oral administration, LA from certain food sources can be converted into CLA in the human intestine to contribute to the prevention and treatment of obesity and hyperlipidemia.

In our modern society, the global information has been integrated. The destiny of a country’s economy and society depends on the social and cultural resources, as well as the cultural innovation and creativity. As the inevitable theme of this era, sustainable development integrates the innovative creative ability into the sustainable architectural design, urban planning and design, public environment design, and private space design, etc. This can solve the environmental problems, social problems, and development problems, existing in some cities, or even in some countries. What’s more, the sustainable design of the environment space takes the environmental factors, socioeconomic factors, and cultural factors into account, which has a positive influence to the ecological sustainable development, and promote the country’s economic and social development. Thereby, it can help us to achieve our goal of sustainable design.

Titanium (Ti) and calcium (Ca), as trappers, were introduced into copper-alloyed metallurgical grade silicon (MG-Si). The effects of trappers on the segregation behavior and removal efficiency of phosphorus (P) were investigated. It was found that P tended to enrich in the TiSi2 and CaCu2Si2 phases, and quenching above the eutectic temperature of Si-Cu alloy is conducive to the P removal. The corrosion process of the P-enriched phases indicated that Ca addition was in favour of P removal, while Ti addition was opposite. The results suggested that though the addition of Ti and Ca could effectively enrich P in the Si-Cu alloy, the acid sensitivity of P-enriched phases would affect the P removal.

Retraction of ‘In situ Raman investigation of the phase transition of NaVO2F2 under variable temperature conditions’ by Sa Zhang et al., RSC Adv., 2021, 11, 23550–23556, https://doi.org/10.1039/D1RA02827H.

The electrochemical performance of lithium iron silicate (Li2FeSiO4) as a cathode material for lithium ion batteries would be remarkably enhanced by selective substitution of 25% oxygen with 25% sulfur to form a Li2FeSiO3S compound based on the previous first-principles calculation. However, the experimental verification has little studied. In this work, the sol-gel precursor and solid-state reaction route was employed to prepare a series of carbon coated Li2FeSiO4 (Li2FeSiO4/C) composites with different sulfur modifications using 1-dodecanethiol as a sulfur source material. The effects of important preparation parameters including sucrose amount, sulfur content, sintering temperature and sintering time on the crystal structure, surface morphology and electrochemical performance of sulfur modified Li2FeSiO4/C composites were investigated through orthogonal design experiments. The results indicated that the significance of the influence on the capacity performance in decreasing order followed sulfur doping content > carbon content > sintering temperature > sintering time. The optimized synthesis conditions were determined to be carbon content of 50% and sulfur doping content of 20% with the sintering temperature at 650°C for 12 h.

The carbon supported PdCu alloyed catalysts (PdCu/C) with different molar ratios of Cu to Pd (Cu/Pd), namely, Cu/Pd=2.0, 3.0, 4.0, and 5.0, were synthesized by a simple and facile two-step method. The Cu nanoparticles were first obtained by microwave assisted method, and then followed by galvanic substitution of Pd on Cu nanoparticles. The PdCu/C catalysts exhibited mainly cubic phase with the average crystallite sizes ranging 4.0~4.5 nm by varying the Cu/Pd ratios of 2.0~5.0. The microstructure and the activity toward oxygen reduction reaction (ORR) of PdCu/C were significantly influenced by the Cu/Pd ratios. The higher degree of alloying and better ORR activity could be achieved with the Cu/Pd=4.0. The half-wave potential (E1/2) reached 0.760 V in the acid medium, which was only 40 mV lower than that of commercial Pt/C. Only 20 mV (2.6%) decrease in E1/2 after 1000 cycles between 0.4 and 1.0 V suggested the good stability.

In this study, titanium was introduced to a Cu-Si alloy as an impurity getter to redistribute boron. A small amount of Ti was melted with Cu-Si alloy, followed by cooling of the alloy to precipitate purified Si crystals which were later separated through multi-step leaching. The effects of Ti content on the distribution of various elements in different phases and microstructure of the solidified alloy were investigated. It was found that Ti in Cu-Si alloy facilitates boron removal by several mechanisms including formation of TiB2 and decreasing the segregation coefficient of B between Si and Cu-Si. Addition of Ti to a Cu-50 wt%Si alloy, compared to silicon metal, showed a significant increase in B removal. An increase in Ti in the range of 1–5% increased B removal, reaching ∼85% at 5% Ti addition. Ti in excess of that required to form TiB2 reacts with Si to generate TiSi2, which collects impurities such as P and Al.

Toxicological data demonstrate that nanoplastics (NPs) can cause direct adverse health effects. However, a method for quantifying NPs in biological samples is lacking to date. In this study, a diatomite associated coagulation-sedimentation extraction (CSE) protocol was developed to selectively enrich polystyrene nanoplastics (PS-NP) from microplastics (PS-MP) in the digest of animal tissues, which were then analyzed using pyrolysis gas chromatography-mass spectrometry. We demonstrate that 0.02 g of 7-μm diatomite can selectively adsorb 70-nm PS-NP in 5 mL oyster digest. The method works in the range of 0.006-5 μg PS-NP per 0.5 g wet weight tissue, which has been verified via samples of environmentally contaminated oysters and chow diet PS-NP-treated C57BL/6 mice (digestive tract, kidney, and liver tissues). The particle size-dependent colloidization or buoyancy theoretically supported the general CSE procedure. This work will pave the way for assessing human exposure to NPs and associated health risks.

Xiamen Xiangan Subsea Tunnel is the first undersea tunnel constructed in China. It has become the major undersea pathway connecting Xiamen Island and Xiangan District since its operation in 2010. The total length is 6.05 km with the undersea length of 4.2 km. In an effort to onsite-monitor reinforcement corrosion in concrete structures, the commercially available CorroWatch multiprobe sensors and ERE-20 reference electrodes were pre-embedded in the selected locations and positions of supporting structures during the tunnel constructions. The real-time data have been collected annually by onsite measurements for 6 years. In this paper, the feasibility of the onsite corrosion monitoring system and suitability of the measured parameters including corrosion current, potential and temperature are discussed based on the preliminary results. The measured typical cyclic-type variations in corrosion current and temperature with monitoring time might be related to the seasonal changes during the annual routine measurements. The widely scattered corrosion potentials that are fluctuated complicatedly reflected localized differences in the vicinity of rebar and concrete. These findings, along with the progressively ongoing research, will provide valuable information in structural durability for service life prediction of reinforced concrete structures exposed to marine environments.

A typical oligomers material, polycarbosilane (PCS) melt, was tested by using the advanced rheumatic expansion system (ARES) with a supplemental data acquisition card and an analog-to-digital converter (ADC). The stress response of the sample at 295 °C to the oscillating shear straining deformation with a 50% shear and an angular frequency of 3.142 rad/s were collected, processed by using the fast Fourier transformation (FFT) technique, and compared to the conventional dynamic stress response of the melt provided by ARES. It was found that the stress response of the melt was no longer sinusoidal and that the main frequency and the amplitude of the stress response were consistent with those provided by the conventional testing method. The PCS at 295 °C behaved like a typical yield fluid when it under the oscillating shear straining deformation with a 50% shear and an angular frequency of 3.142 rad/s.

Gd"2"-"xLa"xO"3 high-k films were deposited on (100) Si substrates by low-pressure metal-organic chemical vapor deposition (MOCVD). The metal-organic precursors we used were Gd and La @b-diketonates. The structure, band gap, composition and electrical properties of Gd"2"-"xLa"xO"3 films have been investigated. X-ray diffraction patterns show that as-deposited thick Gd"2"-"xLa"xO"3 films on Si have formed cubic phase of solid solution with (222) preferred orientation. The band gap of the Gd"2"-"xLa"xO"3 films can be calculated to be 5.78eV using a UV-vis-NIR spectrophotometer. X-ray photoelectron spectroscopy depth profile analyses reveal that there exists an interfacial layer of Gd-La-Si-O silicate and the La element is rich in interfacial layer. The equivalent oxide thickness (EOT) of 1.08nm has been obtained with the flatband voltage (V"f"b) of 1.0V and leakage current density (J"A) of 3A/cm^2 at V"g=V"f"b+1V for Gd"2"-"xLa"xO"3 (x=1.29) films of 8nm physical thickness after 800^oC post-annealing.

A single-source precursor Hf x Zr 1− x (NO 3 ) 4 (HZN) has been successfully synthesized, and used for chemical vapor deposition of Hf x Zr 1− x O 2 films. X-ray photoelectron spectroscopy (XPS) measurement shows that Hf/Zr ratio in the Hf x Zr 1− x O 2 films is in good agreement with that in the precursor determined by inductive coupled plasma (ICP) measurement, indicating precise composition transfer from the precursor to deposited films. Basic characteristics of the Hf x Zr 1− x O 2 films such as chemical bonding, composition, film structure, band gap and electrical properties etc. were carried out using different analysis techniques.

A series of carbon supported palladium copper alloyed catalysts (PdCu/C) were prepared using different molar ratios of Cu to Pd (Cu/Pd), namely, Cu/Pd=1.0, 2.0, 3.0, 4.0, 4.5, and 5.0, by a facile two-step method. The Cu nanoparticles were obtained by microwave assisted route, and followed by the formation of PdCu/C nanoparticles through galvanic substitution of Pd on Cu nanoparticles. The effects of Cu/Pd ratio on the microstructure and electrocatalytic activity of PdCu/C toward oxygen reduction reaction (ORR) were systematically investigated. The as-prepared PdCu nanoparticles exhibited mainly cubic phase with average crystallite sizes ranging 4.7~6.7 nm by varying the Cu/Pd ratio of 1.0~5.0. The higher alloying degree and better ORR activity could be achieved at Cu/Pd=4.5. The half-wave potential (E1/2) reached 0.760 V in 0.1 mol/L HClO4 solution, which was 40 mV lower than that of commercial Pt/C, with a four-electron transfer pathway toward ORR.

La-doped HfO 2 gate dielectric thin films have been deposited on Si substrates using La(acac) 3 and Hf(acac) 4 (acac = 2,4-pentanedionate) mixing sources by low-pressure metal-organic chemical vapor deposition (MOCVD). The structure, thermal stability, and electrical properties of La-doped HfO 2 films have been investigated. Inductive coupled plasma analyses confirm that the La content ranging from 1 to 5 mol% is involved in the films. The films show smaller roughness of ∼0.5 nm and improved thermal stability up to 750 °C. The La-doped HfO 2 films on Pt-coated Si and fused quartz substrates have an intrinsic dielectric constant of ∼28 at 1 MHz and a band gap of 5.6 eV, respectively. X-ray photoelectron spectroscopy analyses reveal that the interfacial layer is Hf-based silicate. The reliable value of equivalent oxide thickness (EOT) around 1.2 nm has been obtained, but with a large leakage current density of 3 A/cm 2 at V g = 1 V + V fb . MOCVD-derived La-doped HfO 2 is demonstrated to be a potential high- k gate dielectric film for next generation metal oxide semiconductor field effect transistor applications.

Hafnium-based dielectrics have been extensively investigated as a possible replacement for SiO2. A novel volatile anhydrous Zr/Hf mixed-metal nitrate precursor ZrxHf1-x(NO3)4(ZHN) was successfully synthesized. ZrxHf1-xO2 thin films were first prepared by the chemical vapor deposition (CVD) technique from the precursor of this mixed-metal nitrate. Differential scanning calorimetry (DSC) and infrared spectra (IR) measurements of ZHN indicated that ZHN may be mixture of single Hf(NO3)4 and a solid solution of Zr(NO3)4 and Hf(NO3)4. The ZrxHf1-xO2 thin films exhibit good dielectric properties with a moderate bandgap value of 5.6 eV and a value for k of 22. ZrxHf1-xO2 is, therefore, a promising candidate for gate-dielectric application, and the anhydrous mixed-metal nitrate can be a potential precursor for high-k materials derived from CVD.

Large-scale cupric oxide (CuO) nanowires have been synthesized by thermal evaporating copper foils in O2 ambient at the temperatures from 300°C to 900°C. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) were performed on the study of the CuO nanowires. XRD studies reveal the possibility of two-steps of nanowire formation; HRTEM image shows the bicrystal structure of the nanowire; SEM studies indicate the relationship between the morphology of the prepared nanowires and the growth conditions. The growth of the nanowires seems to be vapor–solid (VS) mechanism.

In particular, social network service has changed the traditional way of communication between consumers and tourism enterprises, making them to collect information via itself. According to this situation, this thesis takes the users of social network sites as the objects for research, the technology acceptance model as theoretical basis, tourists cognitive trust and emotional trust as intermediate variables, and combines with the usefulness, dependence, openness and community conversation of social network service to build a hypothetical model, and then uses empirical research methods to explore the impact of social network service on tourists purchase intention. The empirical results show that the dependence and community conversation will have a direct positive impact on tourists purchase intention. The results prove the usefulness, dependence, openness, community conversation will have a positive impact on tourists purchase intention. Finally, according to the conclusions this thesis puts forward feasible marketing suggestions for tourism enterprises on how to use social network service, and then describes the outlook for future research.

Combined with literature review, questionnaire survey, statistical analysis and interdisciplinary research, the paper aims to propose a theoretically integrated framework deciphering the relationship between internet word-of-mouth and customers' behavior intention. Based on the literature review and this paper's background, the research model is designed. And then collect survey data through questionnaires, and analyze the research data with SPSS 18.0 & AMOS 17.0. As the result, the study obtains with the theoretical and practical values: (1) The factors of Internet Word of Mouth spread channels, including openness, relationship strength, atmosphere characteristic and authority have influence on customers' behavior intention, in which trust play an intermediary role. (2) The own factors of internet word-of-mouth, including the interests of word of mouth, the number of word of mouth, and the tone of word of mouth impact customers' behavior intention by the trust. And the usefulness of word of mouth and the interaction of word of mouth affect customer behavior intention directly. Finally, the management and marketing advices have been proposed for hotel, including converting the ideas and direction of network marketing, improving and extending the hotel workflow chain, enhancing effective communication with the hotel customers.

The tourism-destination hotel is a combination of hotel and tourist destination. Compared with the traditional hotels, it provides more experiential product and experiential function. This paper focuses on studying the relation between brand experience and customer satisfaction in the tourism-destination hotel. With literature review, questionnaire survey and data analysis, the relation between brand experience and customer satisfaction is explored. And it is proved that perceived value eventually has mediating effect between brand experience factors and customer satisfaction. According to the conclusions, this research provides some suggestions and managerial implications for tourism-destination hotels.

Hafnium-based dielectrics have been extensively investigated as a possible replacement for SiO 2 . Anhydrous Hf/Zr mixed-metal nitrate precursor Hf x Zr 1−x (NO 3 4 (HZN) was successfully synthesized and hafnium zirconate (Hf x Zr 1− O 2 ) thin films were prepared by the chemical vapor deposition (CVD) technique from this precursor. The basal dielectric properties of Hf x Zr 1− O 2 films were studied, and C-V curves with negligible hysteresis are achieved.