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The contradiction between the shortage of urban land and the demand for urban green space needs to be solved reasonably. Different from urban parks, the cooling effect of small green space (SGs) has not been paid enough attention or fully evaluated. The major objective of this research was to explore the cooling and energy saving benefits of SGs with administrative units. The ENVI-met and EnergyPlus models were built based on field measurements on the green space of Xi’an Jiaotong University Qujiang Campus. Field measurement shows that the closer an area to the green space, the lower the air temperature and the higher the relative humidity, especially in the daytime. The ENVI-met results showed that the SGs can reduce the temperature by 0.66 °C within the range of 1260 m × 1350 m compared with the building scene at noon, the EnergyPlus simulation results showed that the building 100 m away from the SGs can reduce the air conditioning energy consumption by 2.1% compared with the distance of 150 m. The research can improve the planning and design standards of urban green space, clarify the cooling and energy saving benefits of SGs, and promote the ecological urban design.

Four new species are described from Jinggang Mountain National Nature Reserve, Jiangxi Province of southern China: Draconarius lingdangsp. nov. (♂♀), D. substrophadatussp. nov. (♀), Orumcekia cipingensissp. nov. (♀) and Tonsilla shuikouensissp. nov. (♀). Additionally, Coelotes septus Wang, Yin, Peng & Xie, 1990 is redescribed and its male is described for the first time.

Crystal materials have received extensive attention due to their extraordinary physical and chemical properties. Among them, phase transition materials have attracted great attention in the fields of photovoltaic, switchable dielectric devices, and ferroelectric memories, etc . However, many of them suffer from low phase transition temperatures, which limits their practical application. In this work, we systematically designed crystalline materials, (TMXM) 2 PtCl 6 (X = F, Cl, Br, I) through halogen substitution on the cations, aiming to improving phase transition temperature. The resulting phase transition of (TMXM) 2 PtCl 6 (X = F, Cl, Br, I) get a significant enhancement, compared to the parent compound [(CH 3 ) 4 N] 2 PtCl 6 ((TM) 2 PtCl 6 ). Such phase transition temperature enhancement can be attributed to the introduction of halogen atoms that increase the potential energy barrier of the cation rotation. In addition, (TMBM) 2 PtCl 6 and (TMIM) 2 PtCl 6 have a low symmetry and crystallize in the space group C 2 /c and P 2 1 2 1 2 1 , respectively. This work highlights the halogen substitution in designing crystal materials with high phase transition temperature.

Many neighbourhoods have traditional characteristics in China; it’s both the wealth of urban and the trouble. With the improvement in the public’s requirements for outdoor living standards, the preservation of the memory of the city block and the transformation of the block brought by the embedding of the new way of life need to be solved properly. Accordingly, this research collected the block patterns and average pedestrian horizontal wind speeds of 12 different formation years based on the plot ratio, building density, building height, enclosure, height fall, aspect ratio and Sky view factors of the traditional blocks in Xi’an. The correlation between various morphological parameters and mean pedestrian horizontal wind speed was discussed. Finally, two types of prediction formulas are obtained, namely the formula of the point concept parameter and the mean pedestrian horizontal wind speed and the formula of the average site conceptual parameter and the average pedestrian horizontal wind speed. This study aims to explore the parameter combinations of traditional block shape optimisation. It also aims to guide the construction activities that improve the outdoor event space quality of modern urban residents in the future. Research methods and results can provide reference for urban and block morphological transformation in similar climate zones.

Black sesame (Sesamum indicum L.) is a Chinese dietary herb that has been widely used in the medical and healthcare fields in China. According to the theory of Traditional Chinese medicine processing, reasonable processing (steaming and drying many times) can increase the tonic effect and reduce the adverse factors generated during long-term use. At present, the processing degree of black sesame is mainly judged based on subjective experience. However, due to the lack of objective and quantitative control indicators, quality fluctuations easily occur. Therefore, for better application, its processing technology needs scientific monitoring methods. Herein a gas chromatography-ion mobility spectrometry (GC-IMS) technique was applied as a monitoring method to differentiate the processed products of black sesame in different processing stages. The response data of volatile components obtained from the samples were processed by the built-in data processing software in the instrument to identify the different components for further principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). From fingerprint comparison, 70 differential signal peaks were screened, 32 of which were qualitatively identified, mainly monomers and dimers of 20 compounds. On this basis, the PCA model shows that there was a significant difference between the raw product (S1) and the processed products (H1-9); moreover, there was a certain correlation between the differential changes of samples in different processing stages (H1-9) and the processing times. The OPLS-DA model specifically shows the differential components in the processing with potential characteristics peaks of 41, 105, n-nonanal, 2 and ethanol can discriminate whether the BS has undergone the first processed. And the dynamic changes of the three characteristic peaks of 1-hexanol, acetic acid and 107 can determine the specific degree of processing of BS. The research proves that GC-IMS combined with a multivariate analysis model can provide scientific data for identifying the characteristic odor components of black sesame.

In the last few decades, the economic activities have been growing fast in slope land of Taiwan. To investigate the effect of slope disturbance by slope utilization on the landslide potential, this study employed the concepts of regional carrying capacity, natural environment, and slope utilization to establish a hazard potential index based on slope land disturbance (IHSD) to define the extent of slope development and utilization. Furthermore, combined with the product of the effective accumulated rainfall (EAR) and the maximum 3-h rolling rainfall intensity (I3Rmax), logistic regression was used to establish a landslide potential model. The results revealed that the landslide grid ratio had a tendency to increase as the IHSD interval value increased, when the IHSD value reached approximately 350 and the rainfall index EAR × I3Rmax exceeded 20,000 (mm2/3 h), landslide probability was high. Moreover, the overall accuracy of the landslide probability assessment model that was established using IHSD combined with rainfall indicators was approximately 78%. As the average rainfall index of each rainfall event increased, the number of historical disaster points located in such areas also generally increased.

The optimized design of natural lighting for residential buildings can greatly reduce lighting energy consumption and improve indoor environmental quality as well as the physical and mental health of residents. Through the DIALux simulation analysis, this paper analyses the importance of natural lighting factors in the Xi'an residential area and analyses factors such as latitude, date, window position, building aspect ratio, building height and window area. The study found that the winter solstice (December 22) is the most unfavourable day for residential lighting in Xi'an. Considering architectural beauty, building energy savings and natural lighting, the winter solstice is an effective time to calculate the window area of residential buildings in Xi'an. The higher the latitude is, the larger the window area required for the house. From April to August, the influence of latitude on window area is small; from January to April and from August to December, latitude has a greater influence on window area. This paper establishes a regression equation for residential window area in Xi'an and provides calculation tools for architects to use when designing residential windows that provides a reference for the design of residential windows at the same latitude (33° north latitude). Intelligent control strategies are put forward on natural lighting in residential buildings for working class families in this paper. An APP on smart phones is developed to realize the intelligent control of curtains. In accordance with family daily routine, the opening width of curtains is controlled automatically based on room functions and exterior illuminance, through which interior illuminance can be adjusted, indoor environmental quality can be improved and energy consumption of HVAC system can be reduced.

Ru has been found to be a highly efficient catalyst for producing γ-valerolactone from the hydrogenation of levulinic acid. However, the active species on Ru nanoparticles (NPs) are still unclear. ...

A numerical simulation and a wind tunnel experiment are performed to investigate the flow field and pollutant dispersion in a two dimensional (2-D) ideal urban street canyon with roofs installed in a viaduct at different heights. Two typical roof shapes are taken into consideration: double flat (DF) and double triangular (DT). The simulation results show that when the height of the viaduct is at 0.875H–0.98H for DF and at 0.71H–0.988H for DT, the main flow field in the canyon will be reversed compared to initial flow field. This reversing phenomenon will aggravate pollution for DF and significantly mitigate pollution for DT compared to levels without a viaduct. The wind tunnel experiment is qualitatively consistent with the numerical simulation results which indicates that this reversing phenomenon is not just theoretical. A mechanism is proposed whereby the viaduct obstructing airflow is the key reason for the flow field reversion.

The work function at the surface of 4,4′Cyclohexylidenebis[N,N-bis(4-methylphenyl) benzenamine (TAPC) layer could be increased by doping MoO3 having high ionization energy. Therefore, in this work, we attempted to dope MoO3 into electron-blocking layer material of TAPC to improve the device performance of organic photodetector (OPD), which effectively suppressed dark current density and increased external quantum efficiency (EQE). When a 5% MoO3 dopant was used, the optimal OPD under reverse-biased of 3 V showed a dark current density of 1.11 nA/cm2, the EQE of 41.8% under a wavelength of 360 nm, and the detectivity of the specific wavelength surpassed 1012 Jones. In this study, we found that the decrease in the dark current density was responsible to the lower energy level of lowest unoccupied molecular orbital of TAPC and slower electron transporting capacity, which enabled the effective suppression of leakage current in OPD under bias. Furthermore, the device's EQE was substantially increased for an optimized concentration of MoO3 doped into TAPC.

There is a persistent H 0-tension, now at more than ≳4σ level, between the local distance ladder value and the Planck cosmic microwave background measurement, in the context of flat Lambda-cold-dark-matter (ΛCDM) model. We reconstruct H(z) in a cosmological-model-independent way using three low-redshift distance probes including the latest data from baryon acoustic oscillation, supernova Ia (SN Ia) and gravitational lensing time-delay (GLTD) observations. We adopt general parametric models of H(z) and assume a Gaussian sound horizon at drag epoch, , from Planck measurement. The reconstructed Hubble constant H 0,rec using Pantheon SN Ia and Baryon Acoustic Oscillations (BAO) data are consistent with the Planck flat ΛCDM value. When including the GLTD data, H 0,rec increases mildly, yet remains discrepant with the local measurement at ∼2.2σ level. With our reconstructions being blind to the dark sectors at low redshift, we reaffirm the earlier claims that the Hubble tension is not likely to be solved by modifying the energy budget of the low-redshift universe. We further forecast the constraining ability of future realistic mock BAO data from Dark Energy Spectroscopic Instrument and GLTD data from Large Synoptic Survey Telescope, combining which, we anticipate that the uncertainty of H 0,rec would be improved by ∼27%, reaching uncertainty level.

Infrared-to-visible transparent upconverter offers an appealing prospect of demonstrating in situ invisible information without interfering with the intrinsic vision of human eyes. However, previous studies required high operational voltage for visible light emission failing to meet the prerequisite of practical application. Here, we report an organic upconversion device composed of a single photoactive material ClAlPc for sensing infrared light and subsequent visualization by BCzPh:CN-T2T exciplex co-hosted phosphorescent light-emitting diode. Incident NIR signal (λmax at 780 nm) is upconverted into visible light emission (λmax at 523 nm) under an onset bias voltage of merely 1.7 V by the virtue of barrier-less bipolar exciplex design. Particularly, the device exhibits linear dynamic luminance toward NIR power density down to 34 μW/cm2 and real-time response to frequency-modulated NIR signal up to 10 kHz. By comprising a transparent multilayered electrode for see-through upconverter, a high-quality infrared visual image with a maximum resolution of 1588 dpi is demonstrated.

Due to their unique semiconductive properties, the application of metal halides as photocatalysts for settling the increasing environmental contaminations has recently gained tremendous attention. Herein, we demonstrated the suitability of a robust hybrid cuprous iodide, namely Cu2I2-bipy (bipy = 4,4′-bipyridine), for photocatalytic reduction of highly toxic Cr(VI). Compared with most known materials, the Cu2I2-bipy photocatalyst has the merits of low cost, easy preparation, good stability and suitable band gap. Further photocatalytic experiments show that Cu2I2-bipy is highly efficient for Cr(VI) reduction with the rapid kinetics, high conversion rate and excellent cycling stability. Theoretical calculations reveal that the separation of valence bands (VBs) and conduction bands (CBs) in Cu2I2-bipy may be the main reason for its excellent photocatalytic performances.

Four thieno[3,2-b]thiophene (TT)-based donor-π-acceptor–type small-molecule donors DTCPTT, DTCPTT-2CN, DTDCPTT, and DTDCPTT-2CN were synthesized and characterized. A clear structure-property relationship correlating the effects of introducing cyano groups onto the TT and the end-capping groups has been successfully established. DTDCPTT and DTDCPTT-2CN were adopted as electron donors for organic photovoltaics (OPVs) mainly due to the strong intramolecular charge transfer absorption in the visible light region, sufficiently high thermal stability, and appropriate energy level alignment with C70. Moreover, the analyses of crystal structures reveal that DTDCPTT and DTDCPTT-2CN form antiparallel dimer pairs through strong dipolar and non-covalent intermolecular interactions. X-ray structures also indicate that introducing cyano groups onto the TT moiety does not affect the backbone planarity significantly. Compared with DTDCPTT-2CN, the more compact and uniform crystal packing renders DTDCPTT advantageous for exciton dissociation and charge carrier transport. DTDCPTT-based device achieves power conversion efficiency as high as 7.81% and 16.89%, respectively, under simulated AM 1.5G illumination and 500 lux TLD-840 fluorescent lamp illumination, which could be attributed to stronger absorption and better photocurrent extraction. In addition, both devices exhibit high stability under continuous simulated 1 sun illumination for more than 300 h. As far as we know, this is the best performance for vacuum-processed small-molecule indoor OPVs to date.

Constitutive activation of Hedgehog (Hh) pathway is intimately related with the occurrence and development of several malignancies, such as medulloblastoma (MB) and other tumors. Therefore, small molecular inhibitors of Hh pathway are urgently needed. In this study, three new steroidal alkaloids, ⊿5 (20R, 24R) 23-oxo-24-methylsolacongetidine, ⊿5 (20S, 24R) 23-oxo-24-methylsolacongetidine and veralinine 3-O-α- l -rhamnopyranosyl-(1 → 2)-β-D-glucopyranoside, together with six known alkaloids, 20-epi-verazine, verazine, protoverine 15-(l)-2′-methylbutyrate, jervine, veramarine and β1-chaconine, were isolated and determined from Veratrum grandiflorum Loes. The dual-luciferase bioassay indicated that all compounds exhibited significant inhibitions of Hh pathway with IC50 values of 0.72–14.31 μM against Shh-LIGHT 2 cells. To determine whether these Hh pathway inhibitors act with the Smoothened (Smo) protein, which is an important oncoprotein and target for this pathway, BODIPY-cyclopamine (BC) competitive binding assay was preferentially performed. Compared with BC alone, all compounds obviously reduced the fluorescence intensities of BC binding with Smo in Smo-overexpression HEK293T cells through fluorescence microscope and flow cytometer. By directly interacting with Smo, it revealed that they were actually novel natural Smo inhibitors. Then, their anti-tumor effects were investigated against the human MB cell line DAOY, which is a typical pediatric brain tumor cells line with highly expressed Hh pathway. Interestingly, most of compounds had slight proliferation inhibitions on DAOY cells after treatment for 24 h same as vismodegib, while β1-chaconine showed the strongest inhibitory effect on the growth of DAOY with IC50 value of 5.35 μM. In conclusion, our studies valuably provide several novel natural Smo inhibitors for potential targeting treatment of Hh-dependent tumors.

Cross-well seismic is a geophysical exploration method, where the seismic source is triggered in one well and the data are accepted in another well, in order to obtain the geological structure between the two wells. In this paper, we mainly study the algorithm of elastic wave reverse time migration imaging with cross-well seismic models. The forward simulations, pre-processing of received data, and reverse time migration imaging are presented. To overcome the problem of large amounts of memory costs in reverse time migration, we develop a saving boundary scheme into cross-well seismic to reduce the memory consumption. The feasibility of our algorithm is verified by a horizontally layered model.

Chemosensory systems play an important role in insect behavior, and some key associated genes have potential as novel targets for pest control. Cacopsylla chinensis is an oligophagous pest and has become one of the main pests of pear trees, but little is known about the molecular-level means by which it locates its hosts. In this study, we assembled the head transcriptome of C. chinensis using Illumina sequencing, and 63,052 Unigenes were identified. A total of 36 candidate chemosensory genes were identified, including five different families: 12 odorant binding proteins (OBPs), 11 chemosensory proteins (CSPs), 7 odorant receptors (ORs), 4 ionotropic receptors (IRs), and 2 gustatory receptors (GRs). The number of chemosensory gene families is consistent with that found in other Hemipteran species, indicating that our approach successfully obtained the chemosensory genes of C. chinensis. The tissue expression of all genes using quantitative real-time PCR (qRT-PCR) found that some genes displayed male head, female head, or nymph-biased specific/expression. Our results enrich the gene inventory of C. chinensis and provide valuable resources for the analysis of the functions of some key genes. This will help in developing molecular targets for disrupting feeding behavior in C. chinensis.

Nonconjugated red fluorescent polymers have been increasingly studied to improve the biocompatibility and penetration depth over conventional fluorescent materials. However, the accessibility of such polymers remains challenging due to the scarcity of nonconjugated fluorophores and lacking relevant mechanism of red-shifted fluorescence. Herein, we discovered that the combination of hydrogen bonding and π-π stacking interactions provides nonconjugated poly(amide-imide) with a large bathochromic shift (>100 nm) from blue-green fluorescence to red emission. The amphiphilic PEGylated poly(amide-imide) derived from in situ PEGylation self-assembled into nanovesicles in water, which isolated the aminosuccinimide fluorophore from the solvents and suppressed the hydrogen bonds formation between aminosuccinimide fluorophores and water. Therefore, the fluorescence of PEGylated poly(amide-imide) in water was soundly retained. Furthermore, the strong hydrogen bonding and hydrophobic interactions with water provided PEGylated poly(amide-imide) with a reversible thermoresponsiveness and presented a concentration-dependent behavior. Finally, accompanied by the excellent biostability and photostability, PEGylated poly(amide-imide) exhibited as a good candidate for cell imaging.

Buildings made of snow and ice in severely cold areas can provide people with tourist experiences. Utilizing natural resources in an appropriate manner such as constructing energy efficient residential buildings that are suited to local climate conditions is important for maintaining indoor thermal comfort, creating ecologically living spaces, and reducing energy consumption. In this study, an igloo was built in the traditional manner at Harbin Institute of Technology to detect the heat transfer mechanism of ice and snow, and indoor thermal comfort in an extremely cold region of China. The thermal benefits of the igloo were investigated based on field measurements. Periodic heat transfer theory was applied to study the heat transfer mechanism in the igloo wall and human thermal comfort was analyzed in the chamber and under ambient conditions. The results showed the following. (1) The air temperature and relative humidity were higher and more stable in the chamber without any heating measures. (2) The air temperature was about 4 °C higher in the chamber than the ambient temperature. (3) The maximum snow depth where the ambient temperature affected the chamber temperature was 200 mm. (4) The igloo provided a more comfortable thermal environment compared with the outdoor conditions. These findings may provide the basis for understanding the thermal benefit of igloos based on the utilization of natural resources. Theoretically and practically, our results may provide an experimental basis for studying the heat transfer mechanism to facilitate the establishment of design and construction standards for snow and ice buildings.

In this study, we demonstrate a novel micro-cavity forming electrode with a sandwiched structure of Ag/HATCN/Ag. This new electrode presents high transmittance in visible wavelengths and reveals the capability of modulating the wavelength of transmitted light by precisely adjusting the thickness of HATCN interlayer. Notably, the Ag/HATCN/Ag electrode possesses excellent thermal stability that leads to an insignificant peak shift of the transmittance spectrum after thermal aging as exposed to air. This new electrode can be applied to both the solution-processed polymer solar cell (PSC) and thermally evaporated small molecule solar cell (SMSC). The implementation of the Ag/HATCN/Ag electrode for the blue, green, and red PSCs with PM6:Y6 as the photoactive blend results in the power conversion efficiency (PCE) over 13%, representing the highest performance for colorful PSCs ever reported. Significantly, the blue PSC shows the highest PCE up to 13.54% with a maximum transmittance of 15.6%. In addition, vacuum-processed red SMSC based on the active layer composed of DTDCPB:C70 blend shows a PCE and a maximum transmittance of 7.84% and 26.4%, respectively, while the blue and green SMSCs also exhibit PCE higher than 7%. The high PCE and the good transmittance of both the PSC and SMSC imply that the new micro-cavity forming Ag/HATCN/Ag electrode has promising potential in various practical applications.

Poly(amide-imide)s (PAIs) present limited use in bioapplications due to their poor aqueous solubility and difficulty in functional accessibility. Herein, we prepared PAI-based prodrugs by leveraging aliphatic PAIs as the polymer scaffolds and conjugating camptothecin (CPT) via thiol-disulfide exchange reaction. The degree of CPT attachment can be smoothly controlled by initial feed ratios of PEG and a pyridinedisulfide-modified CPT precursor. Due to the abundant secondary amine groups in PAI backbones, amphiphilic PAI-CPT prodrugs self-assembled into cationic nanoparticles and showed an efficient cellular internalization (

This study investigates the impacts of tree-planting pattern and tree trunk height on the flow structure and pollutant dispersion inside a street canyon using the numerical model validated by wind tunnel dataset. The isolated canyon of L/H = 10 and W/H = 2 with trees are simulated considering the center tree-planting (CTP) and double rows tree-planting (DRTP) patterns as well as eight trunk heights under perpendicular approaching wind. The results reveal that tree-planting pattern and especially the trunk height affect significantly the flow and pollutant distributions. For each tree-planting pattern, the biggest characteristic of flow structure is, a strong stream of air passes through the canyon, resulting in the disappearance of canyon vortex and corner eddies at the canyon ends when h ≥ H. When compared to treeless case: trees lead to reduced ACH (air exchange rate) ranging from H/3 to 8H/9 and enhanced ACH at h = H and 10H/9; averaged/maximum concentration increases on wall A and slight decreases on wall B are found at h ranging from H/3 to 7H/9, while concentration dramatic decreases on wall A and significant increases on wall B are observed at h = H and 10H/9. Compared to the CTP counterpart, the DRTP present the similar flow structures, ACH and concentration distributions, which indicates that when the total volume and trunk height of trees are the same, the tree-planting patterns have little impacts on the flow structure and concentration distribution. This study will provide technical support for urban road planning to control air pollution.

The fine particles are considered a significant pollution problem. The wet electrostatic precipitators (ESPs) have advantages of efficient collection of the fine particles with lower pressure drop and eliminating reentrainment. The wetting properties of the collector surfaces have significantly important effect on wet ESPs' stable and secure operation. The modified rigid collector (MRC) was modified by coating specific vinyl ester resin composites and loose glass fiber cloth over the conventional carbon steel in a certain way. The rigid collector surfaces before and after modification had been characterized by scanning electron microscopy (SEM) and interface tensiometer. The effect of operating temperatures on the wetting properties of the rigid collector surfaces before and after modification was investigated. The temperature range was 40~90 °C, and the wetting properties contained liquid holdup, surface flow rate, film rate, average film thickness, and critical saturation time. The modified rigid collector surface exhibited excellent wetting properties at the operating temperatures. The fine particles collection performance compared among the MRC, the conventional rigid collector (CRC), and the flexible collector (FC) in the wet ESPs was investigated. The effects of the applied voltage, the water film, corona power, and the specific collecting area on the fine particles collection were evaluated. The modified rigid collector provided high fine particles collection effect with lower energy and water consumption.To improve the submicron particles collection efficiency and decrease energy and water consumption, the formation of uniform water film over the collector surfaces has been widely studied. The modified rigid collector was modified by coating specific vinyl ester resin composites and loose glass fiber cloth (ERGF) over the conventional carbon steel (CCS) in a certain way. The modified rigid collector surface exhibited excellent wetting properties. The wet ESPs by the modified rigid collector exhibited significantly higher particles collection efficiency than by the conventional rigid collector.

In this paper, we use the model dependent method to revisit the constraint on the well-known cosmic distance duality relation (CDDR). By using the latest SNIa samples, such as Union2.1, JLA and SNLS, we find that the SNIa data alone can not constrain the cosmic opacity parameter $\varepsilon$, which denotes the deviation from the CDDR, $d_{\rm L} = d_{\rm A}(1+z)^{2+\varepsilon}$, very well. The constraining power on $\varepsilon$ from the luminosity distance indicator provided by SNIa and GRB is hardly to be improved at present. When we include other cosmological observations, such as the measurements of Hubble parameter, the baryon acoustic oscillations and the distance information from cosmic microwave background, we obtain the tightest constraint on the cosmic opacity parameter $\varepsilon$, namely the 68\% C.L. limit: $\varepsilon=0.023\pm0.018$. Furthermore, we also consider the evolution of $\varepsilon$ as a function of $z$ using two methods, the parametrization and the principle component analysis, and do not find the evidence for the deviation from zero. Finally, we simulate the future SNIa and Hubble measurements and find the mock data could give very tight constraint on the cosmic opacity $\varepsilon$ and verify the CDDR at high significance., 9 pages, 5 figures, 2 tables, Accepted for publication in Physics of Dark Universe

Attention has been focused recently on the harmful effects and malodor of methyl mercaptan (CH3SH), so it is desired to detect CH3SH in situ, sensitively, and selectively. We detected methyl mercaptan via tunable laser absorption spectroscopy (TLAS) with a room-temperature distributed feedback interband cascade laser emitting around 3393 nm and a hollow waveguide gas cell with 5 m length. The fundamental characteristic fingerprint absorptions of CH3SH from 3260 to 3400 nm were examined, and the spectral line 3393.584 nm (corresponding to the ν2 C–H symmetric stretch) was determined to be the optimum for CH3SH detection. The response characteristics of the TLAS system were established by implementing a set of CH3SH concentration gradient experiments with wavelength-scanned direct absorption spectroscopy. The results show that CH3SH TLAS spectra are in excellent agreement with spectra from the Pacific Northwest National Laboratory database; the TLAS response linearity is 0.987, and the detection limit is as low as 25 ppbv (parts per billion by volume, 10−9) with integrated time 1.84 s, corresponding to an absorbance of 1.34 × 10−4 (near the theoretical detection limit). Overall, the TLAS system is a robust method for CH3SH monitoring of industrial waste gas emissions.

In order to improve the keyway broaching process and verify the feasibility of vibration-assisted broaching process, an experimental study on a novel hydraulic vibration assisted broaching (HVAB) system with double-valve electro-hydraulic exciter (DVEHE) is proposed in this paper. The performances of HVAB at different excitation frequencies were compared from three aspects: (a) the cutting force under the different vibration frequencies, (b) the surface roughness of the workpiece, and (c) the flank face wear of the tool. For precision on-line measurement of larger broaching forces, four piezoelectric sensors were fixed on the broaching machine. The experimental results show that HVAB can effectively improve the performance of the broaching process, approximately reduce the broaching force by as much as 9.7% compared to conventional broaching (CB) and improve the surface quality of workpiece. Some explanations are offered to support the observations.

The purpose of the study was to determine the energy performance of a timber structured house built in Harbin, a severely cold region of China. The research team conducted a field test on the house that lasted three months (15 January–15 April 2008). The test included the winter heating energy consumption, average indoor temperature and relative humidity, building heat storage capacity, heat transfer coefficient of the wall, total air volume of air-conditioning system, etc. The test results showed that the total heating was calculated to be 73,240.59 MJ in winter. Thermal imaging tests were carried out on the house and found no obvious thermal defects such as thermal bridges. In conclusion, the timber structured house has a good level of building energy conservation and would provide a good exemplary for green building design and construction in similar severely cold regions in the world.

International audience; Unlike trees, the 3D architecture of gramineous plants is much more related to the shapes of its leaves than the arrangement of its branches. Many modelling efforts have thus concentrated on correctly capturing its complex shape at different stages and use them as scalable geometric primitives. Still, additional control of such objects is needed in the context of Functional Structural Modelling. The objective of this work is to propose a plastic and dynamic 3D leaf model that is well suited for such uses, still able to capture a variety of observed static shapes. Leaf shape is modeled by a parametric surface describing leaf midrib curvature, leaf width variation, undulation of leaf margins and twist along the midrib. Meshes can be generated from these surfaces, and reduced using a decimation algorithm. The model can be fitted with data or with curves drawn by user interaction. Morphological operators are defined and allows for plastic deformation of the control curves. The dynamics of shape acquisition can also be specified, and combined with morphological operators to sim- ulate various scenarios of evolution and responses to stresses. The capabilities of the model are demonstrated through several cases of use. Future directions of research are thought to be a better integration of mechanical or physiological constraints that would reduce the model plasticity but avoid user-induced unrealistic simulation.

UMR AGAP - équipe AFEF - Architecture et fonctionnement des espèces fruitières; International audience; MAppleT is an in silico functional-structural plant model that has been built for simulating architectural development of apple trees. It has the capability of representing tree growth within a virtual space where the development of individual organs depends on geometrical traits. The purpose of this research is to investigate the influence of apple trees x architectural variability on their light interception efficiency. The STAR, namely the silhouette to total area ratio, of leaves, was chosen to evaluate the level of such efficiency. The strategy is to integrate MAppleT with the light interception model provided by the fractalysis module of the VPlants software library. Target values of four major traits (internode length, leaf area, branching angle and top shoot diameter), are varied in range previously observed in a segregating population of apple hybrids. A sensitivity analysis based on polynomial and generalised additive models was performed for highlighting the most influential trait on light interception and suggesting the optimal combination(s) of traits leading to the highest STAR. The contribution of stochastic processes that pilot tree topology in MAppleT is also investigated in the sensitivity analysis. This study not only provides a time- and resource-saving alternative for data collection, but also sets a methodology for ideotype definition and further genetic improvement of apple trees.