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Understanding of the potential leaching of plastic particles, particularly nanoplastics (NPs), from food packaging is crucial in assessing the safety of the packaging materials. Therefore, the objective of this study was to investigate potential exposure risks by simulating the release of NPs from various plastic packaging materials, including polypropylene (PP), general casting polypropylene (GCPP) or metalized casting polypropylene (MCPP), polyethylene (PE), polyethylene terephthalate (PET), and polyphenylene sulfone (PPSU), under corresponding food consumption scenarios. Surface-enhanced Raman scattering (SERS) and scanning electron microscopy (SEM) were utilized to identify and characterize the NPs leached from plastic packaging. The presence of separated NPs was observed in PP groups subjected to 100 °C hot water, GCPP plastic sterilized at a high temperature (121 °C), and PE plastic soaked in 100 °C hot water, exhibited a distorted morphology and susceptibility to aggregation. The findings suggest that the frequent consumption of takeaway food, hot beverages served in disposable paper cups, and foods packaged with GCPP materials may elevate the risk of ingestion of NPs. This reminds us that food packaging can serve as an important avenue for human exposure to NPs, and the results can offer valuable insights for food safety management and the development of food packaging materials.

Clinical evidence shows that postmenpausal women are almost twice as likely to develop Alzheimer's disease (AD) as men of the same age, and estrogen is closely related to the occurrence of AD. Estrogen receptor (ER) α is mainly expressed in the mammary gland and other reproductive organs like uterus while ERβ is largely distributed in the hippocampus and cardiovascular system, suggesting that ERβ selective agonist is a valuable drug against neurodegenerative diseases with low tendency in inducing cancers of breast and other reproductive organs. In this study we identified a natural product patchouli alcohol (PTA) as a selective ERβ agonist which improved the cognitive defects in female APP/PS1 mice, and explore the underlying mechanisms. Six-month-old female APP/PS1 mice were administered PTA (20, 40 mg · kg

The Al2O3 ceramic and Kovar 4 J34 alloy were effectively bonded by vacuum brazing by using an Ag-based filler metal with a composition of Ag-5Cu-1Al-1.25Ti (wt%). The typical interfacial structure of the Al2O3/Kovar 4 J34 joint brazed at 960 °C for 10 min was determined as Al2O3/Ti3(Cu, Al)3O/Ag(s, s) + Cu(s, s) + disperse AlCu2Ti/Ti2Ni + TiFe2/Kovar. The brazing parameters were observed to have a decisive effect on the microstructure evolution and variation of the mechanical properties of the Al2O3/Kovar 4 J34 brazed joints. The maximum shear strength of the brazed joints could reach 150 MPa, and the failure primarily occurred in the ceramic substrate and Ti3(Cu, Al)3O reaction layer. Moreover, the microstructural stability of the Al2O3/Kovar 4 J34 brazed joints at elevated temperatures was also investigated. After thermal cycling at 600 °C for 3 h, the interfacial structure of the brazed joint did not change obviously except for the thickening of the reaction layer, and the joint shear strength remained at 130 MPa. However, the average shear strength of the joint under the testing temperature of 600 °C was reduced to 73 MPa, and the fracture propagated along the Ag matrix of the brazing seam due to the softening of silver.

Average windward area is an important index for calculating the trajectory, velocity attenuation and terminal effect of explosive fragments. In order to solve the problems that existing theoretical method cannot calculate windward area of irregular fragment and experiment method is not convenient for automatic calculation and has low accuracy, a Monte Carlo subdivision projection simulation algorithm is proposed. The average windward area of arbitrary shaped fragments can be obtained with coordinate translation, random rotation, plane projection, convex-hull triangulation, concave boundary searching and sorting with maximum edge length constraint, subdivision area calculation, and averaging by thousands of cycles. Results show that projection area obtained by the subdivision projection algorithm is basically the same as that obtained by software method of computer aided design. Moreover, the maximum calculation error of the algorithm is less than 7%, and its accuracy is much higher than that of the equivalent ellipsoid method. The average windward area calculated by the Monte Carlo subdivision projection simulation algorithm is consistent with theoretical formula for prefabricated fragments, and the error is less than 3%. The convergence and accuracy of the Monte Carlo subdivision projection algorithm are better than those of the icosahedral uniform orientation method.

Background Tuberculosis (TB) is a serious infectious disease caused by Mycobacterium tuberculosis (MTB). An estimated 1.7 billion people worldwide are infected with Mycobacterium tuberculosis (LTBI) during the incubation period without any obvious symptoms. Because of MTB’s high infection and mortality rates, there is an urgent need to develop a fast, portable, and sensitive diagnostic technology for its detection. Methods We included research from PubMed, Cochrane Library, Web of Science, and Embase and extracted the data. MetaDisc and STATA were used to build forest plots, Deek’s funnel plot, Fagan plot, and bivariate boxplot for analysis. Results Forty-six articles were analyzed, the results of which are as follows: sensitivity and specificity were 0.92 (0.91–0.93) and 0.95 (0.94–0.95) respectively. The NLR and PLR were 0.04 (95% CI 0.03–0.07) and 25.32 (95% CI 12.38–51.78) respectively. DOR was 639.60 (243.04–1683.18). The area under the SROC curve (AUC) was 0.99. Conclusions MPT64 exhibits good diagnostic efficiency for MTB. There is no obvious heterogeneity between the three commercial kits.

To investigate the factors affecting the wettability of copper mine blasting dust, the primary blasting dust was collected from an open-pit copper mine and separated into hydrophilic blasting dust (HLBD) and hydrophobic blasting dust (HBBD) using water flotation method. The physicochemical properties of HLBD and HBBD were measured and compared with each other. The properties included particle size distributions (PSDs), micromorphologies, pore structures, mineral components and surface organic carbon functional groups. The results show that particle size and pore structure of the blasting dust are the main factors affecting its wettability. Specifically, particle size of HBBD is smaller than that of HLBD, and their respiratory dust (less than 10 µm) accounts for 61.74 vol% and 53.00 vol%, respectively. The pore structure of HBBD is more developed, and the total pore volume of HBBD is 1.66 times larger than that of HLBD. The identical mineral compositions were detected in HLBD and HBBD by X-rays diffraction (XRD); however, the surface organic hydrophobic component of HBBD is slightly larger than that of HLBD, this may be the reason for the poor wettability of HBBD. This study is significant to understand the effects of physicochemical properties of copper mine blasting dust on its wettability.

Natural products belonging to a class of generally-recognized-as-safe biomaterials have exceptional biocompatibility and biodegradability and can be used as delivery vehicles for a variety of functional foods. Adlay (Coix lacryma-jobi), is a nutritious food, rich in various bioactive ingredients. Coix seed oil extract (CSO) is also bioactive but it is sensitive to oxidation. In this study, a bioactive delivery system based on homologous polysaccharides and proteins was developed to deliver coix seed oil. The results show that the CSO nanoparticles have high encapsulation efficiency, narrow particle size distribution, and good stability. Moreover, the fusion of the nanoparticles with the membrane enabled the transport of CSO through the Caco-2 cell monolayer and improved the intestinal permeability. These findings could provide useful information for designing homologous polysaccharide and protein-based delivery systems to increase the bioavailability of lipophilic nutraceuticals in the food industry.

The closing time of the Paleo-Asian Ocean and the tectonic evolution of the northern margin of the North China Craton are still controversial. The geochronology and geochemistry of the Zhaojinggou monzogranite pluton provide new constraints on the late Paleozoic tectonic evolution and the closure time of the Paleo-Asian Ocean in the southern Central Asian Orogenic Belt (CAOB). The monzogranite yielded a zircon U-Pb age of 286.7 ± 1.2 Ma. Due to the characteristics of low–moderate Mg# values (25.87–39.21), low Fe2O3T values (1.13–1.72), and A/CNK > 1, we show that the pluton is weak peraluminous, high in potassium calc–alkaline series, and displays the feature of S-type granite. The total REE content is low, the distribution curve is right dipping, and the LREE is enriched; the δEu average value is 1.32 (1.11–1.54). The granite presents relatively high (87Sr/86Sr)i values of 0.712345–0.713723, low εNd(t) values of −8.89–−8.21 (an average value of −8.56), and a TDM2 of 1718–1773 Ma. Furthermore, the zircon in situ Hf isotopic analysis shows 176Hf/177Hf ratios of 0.282342 to 0.282614, low εHf(t) values of −9.27–0.38 (mean −4.74), and a TDM2 of 1275–1887 Ma. Additionally, high field strength elements such as Nb, Ta, and Ti are depleted, and large ion lithophile elements, e.g., Rb, Ba, K, and Sr, are enriched. The above features of the Zhaojinggou monzogranite indicate that the pluton was derived from late Paleoproterozoic to Mesoproterozoic lower crustal mafic materials. By discussing the genesis and tectonic implications of the pluton massif, we propose that the Zhaojinggou monzogranite represents a magmatic event caused by the crustal–mantle interaction during the southward subduction of the eastern Paleo-Asian Ocean in the northern margin of the North China Craton during the Early Permian.

Fine tuning of the structures and properties of hydrogen-bonded organic frameworks (HOFs) has been considered to be a huge challenge. Herein, we reported the controlled synthesis of meso-tetrakis(c...

This study explores the key physicochemical factors affecting the hydrophilic characteristics of iron mine blasting dust (BD). The BD is separated into an unwetted part (UWBD, hydrophobic part) and a wetted part (WBD, hydrophilic part). Its particle size, true density (TD), pore parameters, mineral composition, and surface compounds are comprehensively characterized and compared. The results indicate that a smaller particle size and more developed pore parameters are two key factors responsible for the strong hydrophobicity of the BD. The mineral composition of the BD has no direct effect on its wetting properties; however, it indirectly influences the deposition characteristics of the BD in water by affecting its TD. Unlike coal dust, the surface organic composition of the BD does not affect its wettability and the peak area of C-C/C-H hydrophobic groups in the C Is X-ray photoelectron spectrum of the UWBD (45.03%) is smaller than that in the C Is spectrum of the WBD (68.30%). Thus, eleven co-influencing processes of physicochemical properties of the BD on its wettability are summarized. This research sheds light on the key factors affecting the wettability of the BD.

The micromorphology and physicochemical properties of hydrophobic blasting dust (HBD) from an iron mine were comprehensively analyzed by laser particle size analysis (LPSA), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results show that the HBD particles can be classified into three types based on their particle size (PS): larger particles (PS > 10 µm), medium particles (1 µm ≤ PS ≤ 10 µm), and nanoparticles (PS > 1 µm). The cumulative volume of respirable dust (PS > 10 µm) was 84.45%. In addition, three shapes of HBD were observed by SEM: prism, flake, and bulk. In particular, the small particles were mostly flaky, with a greater possibility of being inhaled. Furthermore, the body and surface chemical compounds of HBD were determined by XRD and XPS, respectively. Ammonium adipate (C6H16N2O4) was the only organic compound in the body of HBD, but its mass fraction was only 13.4%. However, the content of organic C on the surface of HBD was 85.35%. This study demonstrated that the small-particle size and large amount of organic matter on the surface of HBD are the main reasons for its hydrophobicity, which can provide important guidance for controlling respirable dust in iron mines.

Two new isostructural iron(II) complexes 1 and 2, with the formula of Fe(1,4-dcb)(N(CN)2)2 (1,4-dcb = 1,4-dichlorobenzene), have been prepared and characterized. 1 was obtained under the ambient condition, whereas 2 was prepared by the application of an external magnetic field with a strength of 0.5 T. Single-crystal X-ray structural analysis and Hirshfeld calculations have revealed that the external magnetic fields have induced the disorder of 1,4-dcb molecules in 2, which strengthened the Cl···N halogen-bonding contacts between 1,4-dcb arrays and one-dimensional (1D) Fe(N(CN)2)2 chains. As a consequence, coplane stacking of 1,4-dcb arrays and 1D Fe(N(CN)2)2 chains has been observed in 2. Compared with the stepped stacking and paramagnetic character for 1, the coplane stacking in 2 has increased the lattice cooperativity and ligand-field strength of N(CN)2, which thus provided partial spin-state transition. While under 1.0 T, the complex was broken and resulted in the formation of crystals Fe(ClO4)·6(H2O...

To study the role of MAPK signaling pathway in the development of Epithelial-mesenchymal transition in oral squamous cell carcinoma induced by inflammatory factor TNF-α. After the action of TNF-α, the expression of JNK, ERK, P38 in MAPK signaling pathway increased and the expression of E-cadherin, Claudin1 decreased significantly compared to the normal control group. After the addition of corresponding inhibitor, the expression of JNK, ERK, P38 decreased and the expression of E-cadherin, Claudin1 increased compared with TNF-α group. TNF-α regulated the role of EMT in promoting the invasion and metastasis of oral squamous carcinoma cells through MAPK signaling pathway.

The currently involved two-dimensional materials (2DMs) are referred to as atomically thin-layered materials, which are composed of in-plane covalent or coordinated crystalline sheets with differen...

The first asymmetric catalytic approach to multilayer 3D chirality has been achieved by using Suzuki-Miyaura cross-couplings. New chiral catalysts were designed and screened under various catalytic systems that proved chiral amide-phosphines to be more efficient ligands than other candidates. The multilayer 3D framework was unambiguously determined by X-ray structural analysis showing a parallel pattern of three layers consisting of top, middle and bottom aromatic rings. The X-ray structure of a catalyst complex, dichloride complex of Pd-phosphine amide, was obtained revealing an interesting asymmetric environment nearby the Pd metal center. Three rings of multilayer 3D products can be readily changed by varying aromatic ring-anchored starting materials. The resulting multilayer products displayed strong luminescence under UV irradiation and strong aggregation-induced emission (AIE). In the future, this work would benefit not only the field of asymmetric synthesis but also materials science, in particular polarized organic electronics, optoelectronics and photovoltaics.

The Linghu Au deposit is located within the northeastern part of the Xiaoqinling region in the southern margin of the North China Craton. Field investigations, cross-cutting relationships, and mineral paragenetic associations have identified three stages of hydrothermal activity. To determine the origin and evolution of ore-forming fluids, and better understand genesis of the Linghu Au deposit, we have undertaken a series of studies including fluid inclusion and He–Ar–H–O–S–Pb isotope systematics. Fluid inclusion study indicates that the early stage of gold mineralization was characterized by a high-temperature and low-salinity H2O–CO2–NaCl hydrothermal fluids that have δD values of – 82.0 to – 78.6‰ and δ18OH2O values of 5.3 to 6.4‰. The intermediate stage of gold mineralization involved moderate temperature H2O–CO2–NaCl hydrothermal fluids with δD and δ18OH2O values of – 92.7‰ to – 87.9‰ and – 1.4‰ to 0‰, respectively. Pyrite samples from this mineralization stage have 3He/4He and 40Ar/36Ar ratios of 0.26–0.31 Ra and 2834.7–4300.6, respectively. The last mineralization stage involved (low-temperature and low-salinity NaCl–H2O system of hydrothermal fluids with relatively lower δD values of – 93.1 to – 92.3‰ and δ18OH2O values of – 5.7 to – 5.2‰. Moreover, sulfides in ores yielded δ34S values of – 3.6 to 5.9‰, with an average of 2.65‰. The sulfides have 206Pb/204Pb ratios of 17.101–17.804, 207Pb/204Pb ratios of 15.438–15.554, and 208Pb/204Pb ratios of 37.438–38.654. The results of fluid inclusions and H–O, S–Pb, and He–Ar isotopes indicate that hydrothermal fluids associated with the early stage of mineralization originated from magmatic fluids, with sulfur and lead being derived from both units of the Taihua Group and a Late Triassic magmatic–hydrothermal system. All of these data indicate that the Linghu gold deposit formed as a result of magmatic–hydrothermal mineralizing processes.

In view of the negative influence of rotor wake (i.e. the aero-olfactory effect, the short name is AO effect) on gas distribution, this paper proposed an AO-effect elimination algorithm for rotor UAV (Unmanned Aerial Vehicle) based three-dimensional (3D) gas distribution mapping (GDM). Firstly, two types of AO effects, i.e. the lateral effect and the vertical effect, were summarized based on experimental phenomena. Secondly, the wake induced gas-patch path was calculated based on the prescribed wake model, and the AO effect was eliminated by estimating the original position of the detected gas patch through backstepping along the induced path. Thirdly, considering the different diffusion speeds along different directions, an ellipsoidal Gaussian distribution rather than the traditional spherical Gaussian distribution mapping method was put forward, which was validated via an experiment conducted using four wireless sensor nodes. The proposed AO-effect elimination algorithm combined with the ellipsoidal kernel GDM has been tested using a robot active olfaction simulator, and the results show that it is more effective in characterizing the gas distribution.

Bipolar disorder (BD) is a debilitating mental disorder with complex clinical manifestations and low diagnostic accuracy. Depressive episodes are most common in the course of BD with high comorbidity and suicide rates, which present greater clinical challenges than mania and hypomania episodes. However, there are no objective biomarkers for bipolar depression. The aim of this study was to detect urinary metabolite biomarkers that could be useful for the diagnosis of bipolar depression. Nuclear magnetic resonance spectroscopy was used to profile urine samples of patients with bipolar depression (n = 37) and healthy volunteers (n = 48). Data were analyzed using Orthogonal Partial Least Square Discriminant Analysis and t-test. Differential metabolites were identified (VIP1 and p0.05), and further analyzed using Metabo Analyst 3.0 to identify associated metabolic pathways. In total, we identified seven metabolites differentially expressed in patients with BD and healthy controls. Compared with healthy group, the levels of betaine, glycerol, hippuric acid, indole sulfate, trimethylamine oxide, and urea in urine samples of BD patients were significantly higher, while the level of inositol was significantly lower. Most of these small molecules are related to lipid metabolism and gut microbiota metabolism. These differential metabolites could provide critical insight into the pathological mechanisms of bipolar depression. The results of this study provide a meaningful reference for similar and further studies in the future.

Maize stalk mulching is a conservation tillage method that has been currently promoted in northeastern China Plain. Remote sensing estimation of regional crop residue cover (CRC) can quickly obtain the information of straw mulching in a large area, which plays an important role in monitoring and popularizing the work of straw mulching. In this study, the normalized difference til-lage index (NDTI), simple tillage index (STI), normalized difference residue index (NDRI), and normalized difference index 7 (NDI7) were extracted from Sentinel-2A image and used to establish a linear regression model for CRC and spectral indices in Lishu County of Jilin Province. The results showed that soils had strong spatial heterogeneity in the study area, which would lead to a significant impact on the spectral index regression model. Using soil texture classification (zoning) to establish regression model could improve the inversion accuracy. Soil spatial heterogeneity would increase the estimation error of the model. The four spectral indices had a strong correlation with CRC, among which the NDTI and STI models performed better. The zonal linear regression model based on NDTI and STI verified that R玉米秸秆覆盖还田是东北平原当前大力推广的一种保护性耕作方式。区域作物秸秆覆盖度(CRC)的遥感估算可大范围快速获取耕地秸秆覆盖还田信息,对于政府监测和推广秸秆覆盖还田工作有重要作用。本研究以吉林省梨树县为研究区,基于Sentinel-2A卫星影像,选取归一化耕作指数(NDTI)、归一化秸秆指数(NDRI)、简单耕作指数(STI)和归一化差值指数(NDI7)4种光谱指数,建立光谱指数与玉米秸秆覆盖度的线性回归模型,进行秸秆覆盖度反演。结果表明: 研究区土壤背景空间异质性较强,对光谱指数回归模型影响显著,采用土壤质地分类(分区)分别建立回归模型的方法可提高反演精度。土壤背景空间异质性会增大模型估算误差;4种光谱指数与玉米秸秆覆盖度均有较强相关性,其中,NDTI和STI模型表现更好;基于NDTI和STI的分区线性回归模型验证

Subtle integration of rotatable polar components into dielectric crystals can contribute significantly to adjustable switching temperatures (Ts) and dielectric relaxation behaviors. Currently, one of the biggest challenges lies in the design of optimal polar components with moderate motion resistance in a crystalline system. In this work, we demonstrate that under refrigerator conditions, rotatable hydrogen-bonded one-dimensional (1D) cationic chains, {[C2H6N5]+}n (C2H6N5 = 3,5-diamino-1,2,4-triazolinium), and two-dimensional (2D) anionic layers, {[(H2O)2·SO4]2–}n, can be generated in an organic salt, 3 ([C2H6N5]2·[(H2O)2·SO4]). Compared with the nonhydrated precursor, 2 ([C2H7N5]·[SO4]), the rotation of these 1D and 2D ionic species triggers a reversible phase transition and dielectric switching in 3. In addition, the significantly sluggish rotation of the 1D cationic chains from parallel to unparallel stacking and the counter-clockwise rotation of the 2D anionic layers, compared with their reverse proce...

Combining the advantages of ultrathin two-dimensional (2D) nanosheets featuring stimuli-responsive properties with lanthanide-doped upconverting nanoparticles (UCNPs) represents a challenging goal in near infrared (NIR) light-triggered molecular switching under ambient conditions. Here, we present the fabrication of a 2D@UCNPs hybrid system comprising the integration of distinct features of atomically thin 2D spin-crossover nanosheets ({[Fe(1,3-bpp)2(SCN)2]2}n) and ytterbium ion (Yb3+)-sensitized hexagonal phase UCNPs [sodium yttrium fluoride (NaYF4): 20 mol% Yb3+, 1 mol% erbium ions (Er3+)]. The UCNPs are hybridized with 2D nanosheets involving bare thiocyanate (SCN−) ligands on both sides of the basal surfaces of the nanosheets, and as a consequence, effective synergistic effects between the up-conversion luminescence (UCL) and spin-state interconversion were established. Upon NIR (980 nm) irradiation, the UCL weakened the metal-to-ligand charge-transfer (MLCT) and triggered high-spin (HS) to low-spin (LS) state transition. Upon subsequent heating (40 °C), the MLCT strengthened and the LS to HS state transition was achieved, suggesting a reversible molecular-switching had occurred which was triggered by altering NIR and thermal stimuli. In addition, the corresponding aqueous colloidal suspension is highly stable, nontoxic, environmentally and human friendly in nature, making it suitable for practical applications in photo-switching devices and fabrication of next-generation user-friendly and wearable, fashionable optoelectronic devices.

Combining the fascinating advantages of ultrathin two-dimensional (2D) nanosheets with the nanostructuration of spin-crossover (SCO) materials represents an attractive target of controlled fabrication of SCO nano-objects at the device level. Here, we demonstrate that through facile-operating ultrasonic force-assisted liquid exfoliation technology the three-dimensional (3D) van der Waals SCO bulk precursor {[Fe(1,3-bpp)

Pelvic osteotomy is commonly used to adjust acetabula dysplasia for congenital dislocation of the hip, whereas congenital insensitivity to pain with anhidrosis (CIPA) is a rare hereditary disease that often has the characteristics of joint development deformity and easy fracture. This article reports the case involving a CIPA patient who was surgically treated by Chiari pelvic osteotomy and proximal femoral rotation osteotomy for congenital dislocation of the left hip joint and was provided long-term follow-up for redislocation and bilateral femoral head absorption.

Waterborne pathogens and their associated diseases are major threats to public health, and surveillance of pathogens and identification of the sources of pollution are imperative for preventing infections. However, simultaneously quantitative detection of multiple pathogens and pollution sources in water environments is the major challenge. In this study, we developed and validated a highly sensitive (mostly >80%) and highly specific (>99%) high-throughput quantitative PCR (HT-qPCR) approach, which could simultaneously quantify 68 marker genes of 33 human pathogens and 23 fecal markers of 10 hosts. The HT-qPCR approach was then successfully used to investigate pathogens and fecal pollution in marine recreational water samples of Xiamen, China. Totally, seven pathogenic marker genes were found in 13 beach bathing waters, which targeted Acanthamoeba spp., Clostridium perfringens, enteropathogenic Escherichia coli, Klebsiella pneumoniae, Vibrio cholera/V. parahaemolyticus and Legionella spp.. Fecal markers from human and dog were the most frequently detected, indicating human and dog feces were the main contamination in the recreational waters. Nanopore sequencing of full-length 16S rRNA gene revealed that 28 potential human pathogens were detected and electrical conductivity, salinity, oxidation-reduction potential and dissolved oxygen were significantly correlated with the variation in bacterial community. Our results demonstrated that HT-qPCR approach had the potential rapid quantification of microbial contamination, providing useful data for assessment of microbial pathogen associated health risk and development of management practices to protect human health.

As a source searching method, infotaxis has been used in mobile olfactory robots equipped with contact-type MOS (metal oxide semiconductor) gas sensors. This method navigates a robot to explore more cues in the global space and therefore costs much time at the early stage. To solve this problem, this paper presents a line integral infotaxis (LII) algorithm which is realized by applying a remote-type TDLAS (tunable diode laser absorption spectroscopy) gas sensor to the infotaxis. In addition, the robot often gets stuck in the place of high concentration during the infotaxis searching process, so an odor source declaration procedure which is implemented by calculating the odor particle flux on a closed curve is added to the LII. Simulation results show that the LII algorithm can enormously save time of exploration and solve the local convergence problem.

Precise revealing the mechanisms of excited-state intermolecular proton transfer (ESPT) and the corresponding geometrical relaxation upon photoexcitation and photoionization remains a formidable challenge. In this work, the compound (E)-4-(((4H-1,2,4-triazol-4-yl)imino)methyl)-2,6-dimethoxyphenol (TIMDP) adopting a D-π-A molecular architecture featuring a significant intramolecular charge transfer (ICT) effect has been designed. With the presence of perchloric acid (35 %), TIMDP can be dissolved through the formation of a HClO4 -H2 O-OH(TIMDP)-N(TIMDP) hydrogen-bonding bridge. At the ground state, the ICT effect is dominant, giving birth to crystals of TIMDP. Upon external stimuli (e.g., UV light irradiation, electro field), the excited state is achieved, which weakens the ICT effect, and significantly promotes the ESPT effect along the hydrogen-bonding bridge, resulting in crystals of [HTIMDP]+ ⋅[H2 O]⋅[ClO4 ]- . As a consequence, the mechanisms of the ESPT can be investigated, which distorted the D-π-A molecular architecture, tuned the emission color with the largest Stokes shift of 242 nm, and finally, high photoluminescence quantum yields (12 %) and long fluorescence lifetimes (8.6 μs) have achieved. These results not only provide new insight into ESPT mechanisms, but also open a new avenue for the design of efficient ESPT emitters.

The existing electronic nose (e-nose) chamber has problems in design, such as large volume, unreasonable structure and so on, so it cannot be well used in handheld e-nose systems. Inspired by the structural characteristics of mammalian nasal cavity, seven design schemes of handheld e-nose bionic chamber for liquor recognition were proposed in this paper. Firstly, through fluid dynamics simulation, the effects of chamber shape and internal structure on airflow uniformity, flow velocity, air pressure and residual gas were compared comprehensively. On this basis, the bionic chamber with the best comprehensive performance was selected. Then, the selected bionic chamber and the ordinary square gas chamber were installed in the self-made handheld e-nose system and used in the identification experiments of six liquors. The results show that the selected bionic chamber has higher recognition rate.

Ultra-thin two-dimensional (2D) nanosheets of Zn-based metal -organic framework (MOF) were prepared from the precursor [Zn(bpydc) (H2O)·H2O]n (bpydc = 2,2′-bipyridine-5,5′-dicarboxylate), by using a liquid phase ultrasonic stripping technique. The atomic thickness and the abundant oxygen atoms making the nanosheets are well dispersed in various solvents, exhibiting unique fluorescence responses to solvents of different polarities. Adding on, by loading on the ytterbium ion (Yb3+)-sensitized hexagonal phase up-converting nanoparticles (UCNPs, sodium yttrium fluoride (NaYF4): 20 mol% Yb3+, 1 mol% erbium (Er3+ ions)) on the surfaces of nanosheets, the in-situ near infrared (NIR) light (980 nm) triggered luminescence enhancement has been observed, suggesting the favorable application foreground in biomedical science, super-capacitors, and electronic devices.

Indoor smell affects human health and work efficiency. In order to reduce the impact of indoor smell on human health and work efficiency, a novel indoor smell regulation method was proposed. First, an indoor smell regulation system, including wireless sensor nodes (WSNs), a smell presenting device (SPD), and a wireless control node, was designed. Second, the number and location of WSNs were optimized by combining the computational fluid dynamics with the ant colony optimization algorithm. Third, the location of the SPD was determined according to the diffusion speed, uniformity of distribution, total number of indoor smell particles, and average smell concentration of the breathing section. Finally, experiments were conducted and the results show that the smell regulation system can quickly and effectively detect and remove the unpleasant smell and then release the pleasant smell. Generally, the smell regulation system is capable of performing an indoor smell adjustment in less than 5 min.

The design and preparation of a porous high-valence metal-organic framework (MOF) featuring open coordination sites are of utmost importance for the development of adsorbent materials. Here in this work, the three-dimensional (3D) high-valence MOF [Er(dcbp)

To investigate the diverse solvent effect on extraction of chemical components from Lamiophlomis rotata.Based on LC-MS / MS technique, and chromatographic peak comparison, potential chemical components screening and partial least squares-discriminant analysis( PLS-DA) were used to establish a quantitation method for simultaneous determination of chlorogenic acid,forsythoside B,verbascoside,luteoloside,quercetin,luteolin and apigenin.According to the results of PLS-DA and quantitative analysis, methanol, water-saturated n-butanol,75% methanol and 50% methanol showed wider extraction range and higher extraction efficiency to the chemical components of Lamiophlomis rotata.This study offeres references to the extraction technology of Lamiophlomis rotata, and promotes the relative pharmacodynamics study of this medical material.

This paper described an experiment which was designed to validate the effectiveness of an aerodynamic olfactory effect model for the simulation of gas-sensitive rotorcrafts. The model simulates the rotor wakes using free vortices and calculates the distortion of the gas plume using filament based plume model. We designed an experiment in which a camera recorded the distortion of the smoke plume, and proposed a practical video processing routine to extract the smoke dispersion trajectory. Then the trajectory was compared with the simulated one to validate the model. Results showed that this aerodynamic olfactory effect model is a credible way to simulate odor diffusion process under the influence of quadrotor.