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The equity of mandatory building energy efficiency design standards (BEEDSs) has not received sufficient attention, for there is little study emphasizing the equity between the rich and the poor from the perspective of mandatory energy policies. Therefore, this study is aimed at evaluating the heterogeneous effect of BEEDSs on the energy consumption of households with varying incomes based on household-level data (n = 1196) from Chongqing in China. The study indicates that the actual energy efficiency of the high-income group is 47%, whereas those of the middle- and low-income groups are 32% and 25%, respectively, compared to groups in the absence of BEEDSs. Furthermore, the energy-saving benefits of the rich are approximately twice that of the poor. Also, the Lorenz curve is used to describe the inequality in the distribution of energy-saving benefits, showing that the inequality coefficient is 0.25. This study provides a strong reference for the research and policy-making related to building energy efficiency.
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The climatic conditions in different regions of China are complex and diverse, and the characteristics of building energy consumption in different climatic regions are quite different, leading to significant differences in the historical peak situation of building carbon emissions (BCE). Based on the statistical Mann-Kendall (MK) trend test method, this study evaluates the historical peak situation of BCE in different climate regions in China and discusses the reasons for the differences in the growth trends and peak situations of BCE in these regions. Furthermore, according to the characteristics of building energy consumption in different climate regions, the challenges faced by each climate region in promoting the peaking of BCE are highlighted. The research results show that owing to the continuous increase in the proportion of electrification and clean energy power generation, the electricity emission factor and carbon emissions per unit of energy consumption continue to decline, and the growth rates of BCE in the transitional and southern regions are significantly lower than the growth rate of building energy consumption, and the carbon emissions per unit floor area in the southern region has reached its peak. The main obstacles to promoting the peaking of BCE in the northern heating region are the highcarbon heating energy structure and the unrestrained heating behavior of residents, while the challenges faced by the transitional and southern regions are the southward migration of the population and economic centers of gravity and the gradual increase in residents' requirements for living environment comfort. Government decision-makers should formulate differentiated BCE peaking strategies according to the characteristics of building energy consumption in different climate regions.
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As a tropical flower, Nymphaea lotus is a typical night-blooming waterlily used in water gardening. Its petals are rich in aromatic substances that can be used to extract essential oils and as flower tea. However, the short life of the flower seriously affects the development of its cut flowers. At present, neither the mechanism behind the night-opening waterlily flower's opening and closing nor the difference between day-opening and night-opening waterlily flowers' opening and closing mechanisms are clear. In this study, endogenous hormone contents of closed (CP) and open (OP) petals were measured, and transcriptome analysis of CP and OP petals was carried out to determine the signal transduction pathway and metabolic pathway that affect flower opening and closing. ABA and cell wall modification were selected as the most significant factors regulating flowering. We used qRT-PCR to identify the genes involved in the regulation of flower opening in waterlilies. Finally, by comparing the related pathways with those of the diurnal type, the obvious difference between them was found to be their hormonal regulation pathways. In conclusion, the endogenous ABA hormone may interact with the cell wall modification pathway to induce the flowering of N. lotus. Our data provide a new direction for the discovery of key factors regulating the flower opening and closing of N. lotus and provide basic theoretical guidance for future horticultural applications.
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Nymphaea , Nymphaea/genética , Ácido Abscísico/metabolismo , Flores/metabolismo , Perfilación de la Expresión Génica , Hormonas/metabolismo , Pared Celular , Regulación de la Expresión Génica de las Plantas , TranscriptomaRESUMEN
To study the influence of the gangue content of coal gangue particles on the vibration signal of the tail beam under sliding condition, this paper combines three-dimensional(3D) laser scanning technology with the finite element method, establishes a finite element model of the real shape of coal gangue particles and the hydraulic support in top coal caving in LS-DYNA, analyzes the influence of gangue content on some characteristics of the acceleration signal on the tail beam in the time and frequency domains, and then studies the influence of the size and total mass of the rock, and the angle of the tail beam on the characteristics. The following conclusions are obtained: when the coal gangue particles slip on the tail beam, an increase in gangue content significantly improves the effective value of the acceleration signal of the tail beam in the time domain and the average power and average amplitude in the frequency domain. With different sizes, total masses, and tail beam angles, the increase in gangue content always causes an increase in acceleration signal characteristics. In terms of the influence of various factors on the same gangue content, at the same total mass, the larger the rock mass size is, the faster the characteristic value increases with the increase in gangue content. The greater the total mass, the greater the value of the acceleration signal characteristics. A smaller angle between the tail beam and the ground increases the value of each characteristic. The results of this study provide a reference for further research on coal gangue identification based on vibrations.
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Carbón Mineral , VibraciónRESUMEN
In this study, metabolome of open petals (OP) and closed petals (CP) from Nymphaea 'Blue Bird' was firstly investigated. A total of 455 metabolites was identified in Nymphaea 'Blue Bird' petals, which was mainly composed of 100 flavonoids, 83 phenolic acids, 64 amino acids and derivatives, 60 lipids, 32 alkaloids, 32 organic acids, 24 nucleotides and derivatives, and 12 lignans and coumarins. By differential analysis, 192 metabolites were identified with variable importance in project ≥ 1, among which 83 and 109 metabolites were up- and down-regulated in OP group, respectively. Further analysis (Log2 fold change ≥ 1) identified 26 and 7 metabolites exhibited significantly lower and higher contents in CP group, relative to OP group. Importantly, KEGG analysis indicated that flavonoid biosynthesis exhibited the most significant enrichment. qRT-PCR analysis indicated that the PAL, CHS, and HCDBR genes showed a significantly higher expression in OP group than in CP group. These data explain the increase of naringenin chalcone and phloretin in OP. However, there was no significant difference of total flavonoids between OP and CP groups. Considering the increase of H2O2 content and ultraviolet (UV) absorption peak in OP, our results implied that diurnal stressful conditions induced the degradation of flavonoids, which contributed to environmental stress amelioration. Moreover, a higher absorption peak of 360-380 nm UV was observed in the extract liquor of OP. The sensitivity maximum of the UV-photoreceptor of bees is situated around 340-380 nm UV. This suggested, as noted for the maximum absorption of dihydrokaempferol in 340-370 nm, rhythmic accumulation and loss of these differential flavonoids in Nymphaea 'Blue Bird' petals might enhance UV pattern to some degree, influencing pollinator attraction.
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Flavonoides/biosíntesis , Flores/química , Flores/metabolismo , Nymphaea/química , Nymphaea/metabolismo , Feromonas/metabolismo , Pigmentación/fisiología , Adaptación Fisiológica/fisiología , Animales , Abejas , Metaboloma , Metabolismo Secundario/fisiologíaRESUMEN
Most waterlily flowers open at dawn and close after noon usually for three to four days, and thereafter wilt. The short lifespan of flowers restricts the development of the flower postharvest industry. The termination of flower movements is a key event during flower aging process. However, it is still unclear when the senescence process initiates and how it terminates the movement rhythm. In this study, we observed that the opening diameter of flowers was the smallest on the fourth (last) flowering day. Subsequent transcriptome profiles generated from petals at different flowering stages showed that the multiple signaling pathways were activated at the last closure stage (Time 3, T3) of the flowers, including Ca2+, reactive oxygen species and far red light signaling pathways, as well as auxin, ethylene and jasmonic acid signaling pathways. Moreover, In terms of cell metabolism regulation, the genes related to hydrolase (protease, phospholipase, nuclease) were upregulated at T3 stage, indicating that petals entered the senescence stage at that time; and the genes related to water transport and cell wall modification were also differentially regulated at T3 stage, which would affect the ability of cell expand and contract, and eventually lead to petal not open after the fourth day. Collectively, our data provided a new insight into the termination of flower opening in the waterlilies, and a global understanding of the senescence process of those opening-closure rhythm flowers.
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A novel CMOS-process-compatible high-holding voltage silicon-controlled rectifier (HHV-SCR) for electrostatic discharge (ESD) protection is proposed and demonstrated by simulation and transmission line pulse (TLP) testing. The newly introduced hole (or electron) recombination region H-RR (or E-RR) not only recombines the minority carrier in parasitic PNP (or NPN) transistor base by N+ (or P+) layer, but provides the additional recombination to eliminate the surface avalanche carriers by newly added P+ (or N+) layer in H-RR (or E-RR), which brings about a further improvement of holding voltage (Vh). Compared with the measured Vh of 1.8 V of low-voltage triggered silicon-controlled rectifier (LVTSCR), the Vh of HHV-SCR can be increased to 8.1 V while maintaining a sufficiently high failure current (It2 > 2.6 A). An improvement of over four times in the figure of merit (FOM) is achieved.
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An ultra-low specific on-resistance (Ron,sp) lateral double-diffused metal-oxide-semiconductor transistor (LDMOS) with enhanced dual-gate and partial P-buried layer is proposed and investigated in this paper. On-resistance analytical model for the proposed LDMOS is built to provide an in-depth insight into the relationship between the drift region resistance and the channel region resistance. N-buried layer is introduced under P-well to provide a low-resistance conduction path and reduce the resistance of the channel region significantly. Enhanced dual-gate structure is formed by N-buried layer while avoiding the vertical punch-through breakdown in off-state. Partial P-buried layer with optimized length is adopted under the N-drift region to extend vertical depletion region and relax the electric field peak in off-state, which enhances breakdown voltage (BV) with low drift region resistance. For the LDMOS with enhanced dual-gate and partial P-buried layer, the result shows that Ron,sp is 8.5 mΩ·mm2 while BV is 43 V.
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An AlGaN/GaN lateral reverse blocking current regulating diode (RB-CRD) with trench Schottky anode and hybrid trench cathode has been proposed and experimentally demonstrated on silicon substrate. The Schottky barrier diode (SBD) integrated in the anode exhibits a turn-on voltage of 0.7 V and a reverse breakdown voltage of 260 V. The hybrid trench cathode acts as a CRD, which is in series connection with the anode SBD. A knee voltage of 1.3 V and a forward operation voltage beyond 200 V can be achieved for the RB-CRD. The RB-CRD is capable of outputting an excellent steady current in a wide temperature range from 25 to 300 °C. In addition, the forward regulating current exhibits small negative temperature coefficients less than - 0.152%/oC.
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Conductance method was employed to study the physics of traps (e.g., interface and bulk traps) in the Al2O3/GaN MOS devices. By featuring only one single peak in the parallel conductance (G p/ω) characteristics in the deep depletion region, one single-level bulk trap (E C-0.53 eV) uniformly distributed in GaN buffer was identified. While in the subthreshold region, the interface traps with continuous energy of E C-0.4~0.57 eV and density of 0.6~1.6 × 1012 cm-2 were extracted from the commonly observed multiple G p/ω peaks. This methodology can be used to investigate the traps in GaN buffer and facilitates making the distinction between bulk and interface traps.
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Swimming in surface water bodies (e.g., lakes, rivers) can expose the human body to substantial risk of infection by Cryptosporidium. These findings are from a one-year investigation on the occurrence and distribution of the protozoan parasite Cryptosporidium in Yunlong Lake, Xuzhou, China. Cryptosporidium oocysts were detected by immunofluorescence microscopy. From January to November of 2015, 180 samples (120 water samples and 60 sediment samples) were collected and analyzed. Among them, 42 (35%) water samples and 28 (47%) sediment samples tested positive for Cryptosporidium. The concentration of Cryptosporidium oocysts in the water samples was 0-8/10 L and 0-260/g in sediment samples. Results revealed that July was the highest risk period for both swimming and diving with an estimated probability of infection from swimming of greater than 18 per 10,000 swim sessions. It was concluded that swimming or diving in Yunlong Lake has a higher risk of Cryptosporidium infection than the acceptable risk level set by the United States Environmental Protection Agency. Thus, regular monitoring of water quality in recreation water bodies is strongly recommended.
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Ag(I)-mediated in situ generation of 3,3'-azobis(1,2,4-triazole) (AzTAZ) from 3-amino-1,2,4-triazole (AmTAZ) through dehydrogenative coupling has been realized during the crystallization process of two Cd(II) coordination polymers with novel topological architectures: a (3, 4, 5)-connected (4 x 6(2))(2)(4 x 6(7) x 8(2))(2)(6(5) x 10) net for [Cd(2)(AmTAZ)(2)(AzTAZ)](n) (1) and a 4-connected (6(2) x 8(4))(6(4) x 8(2))(6(5) x 8)(2) net for [Cd(AzTAZ)(2)(H(2)O)](n) (2), whereas AmTAZ retains its original form in a heterometallic complex, [Ag(2)Cd(AmTAZ)(4)](n) (3).
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Amitrol (Herbicida)/química , Cadmio/química , Compuestos Organometálicos/síntesis química , Polímeros/química , Plata/química , Triazoles/síntesis química , Hidrogenación , Compuestos Organometálicos/química , Triazoles/químicaRESUMEN
Three isomorphous lead(II) complexes with a new {N(3)SX}-coordinated (X = Cl, Br, I) mode have been synthesized and characterized by X-ray diffraction. The structural analyses reveal that the coordination environment around the center metal is distinctly influenced by the stereochemical 6s(2) lone pair and N-H...X hydrogen bonds. Additionally, doubly deprotonated trzS(2-) (HtrzSH = 1,2,4-triazole-3-thiol) generated in situ via deamination and dehydrazination of ahtrzS(-) (ahtrzSH = 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole) was first observed in a semiconducting three-dimensional coordination network at higher reaction temperature.
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The hydro(solvo)thermal reactions of Pb(OAc)(2).3H(2)O with the aromatic carboxylic ligands 1,3,5-benzenetricarboxylic and 1,4-, 1,2-, and 1,3-benzenedicarboxylic acids (1,3,5-H(3)BTC; 1,4-, 1,2-, and 1,3-H(2)BDC) have yielded a family of inorganic-organic framework materials: [Pb(2)(1,3,5-BTC)(mu(3)-OH)(H(2)O)](n) (Iota), [NaPb(1,3,5-BTC)(H(2)O)](n) (IotaIota), [Pb(1,4-BDC)](n) (IotaIotaIota), [Pb(5)(1,2-BDC)(4)(OAc)(2)](n) (IV), and {[Pb(5)(1,3-BDC)(5)(H(2)O)(2)](2).H(2)O}(n) (V). These complexes have been characterized by means of single-crystal X-ray diffraction, X-ray powder diffraction, thermogravimetric analysis-mass spectrometry, and photoluminescence spectra. They are all three-dimensional structures except for two-dimensional IV. Topology analysis reveals that complexes I an V represent rare (4,8)-connected flu and (3,4)-connected zeolite-like nets, respectively. The five complexes exhibit diverse inorganic connectivity, including a 0D Pb(4)O(16) cluster for I, a 1D Pb-O-Pb chain for II, a 2D Pb-O-Pb network for III and IV, and an unprecedented 3D Pb-O-Pb framework for V. And the diversity in inorganic arrays leads to differences in luminescent properties of these complexes.
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To study the conversion from a meso form to a racemic form of tetrahydrofurantetracarboxylic acid (H(4)L), seven novel coordination polymers were synthesized by the hydrothermal reaction of Zn(NO(3))(2)6 H(2)O with (2S,3S,4R,5R)-H(4)L in the presence of 1,10-phenanthroline (phen), 2,2'-bipyridine (2,2'-bpy), or 4,4'-bipyridine (4,4'-bpy): [Zn(2){(2S,3S,4R,5R)-L}(phen)(2)(H(2)O)]2 H(2)O (1), [Zn(4){(2S,3R,4R,5R)-L}{(2S,3S,4S,5R)-L}(phen)(2)(H(2)O)(2)] (2), [Zn(2){(2S,3S,4R,5R)-L}(H(2)O)(2)]H(2)O (3), [Zn(4){(2S,3R,4R,5R)-L}{(2S,3S,4S,5R)-L} (2,2'-bpy)(2)(H(2)O)(2)]2 H(2)O (4), [Zn(2) {(2S,3S,4R,5R)-L}(2,2'-bpy)(H(2)O)] (5), [Zn(4){(2S,3R,4R,5R)-L}{(2S,3S,4S,5R)-L} (4,4'-bpy)(2)(H(2)O)(2)] (6), and [Zn(2) {(2S,3S,4R,5R)-L}(4,4'-bpy)(H(2)O)] 2 H(2)O (7). These complexes were obtained by control of the pH values of reaction mixtures, with an initial of pH 2.0 for 1, 2.5 for 2, 4, and 6, and 4.5 for 3, 5, and 7, respectively. The expected configuration conversion has been successfully realized during the formation of 2, 4, and 6, and the enantiomers of L, (2S,3R,4R,5R)-L and (2S,3S,4S,5R)-L, are trapped in them, whereas L ligands in the other four complexes retain the original meso form, which indicates that such a conversion is possibly pH controlled. Acid-catalyzed enol-keto tautomerism has been introduced to explain the mechanism of this conversion. Complex 1 features a simple 1D metal-L chain that is extended into a 3D supramolecular structure by pi-pi packing interactions between phen ligands and hydrogen bonds. Complex 2 has 2D racemic layers that consist of centrosymmetric bimetallic units, and a final 3D supramolecular framework is formed by the interlinking of these layers through pi-pi packing interactions of phen. Complex 3 is a 3D metal-organic framework (MOF) involving meso-L ligands, which can be regarded as (4,6)-connected nets with vertex symbol (4(5).6)(4(7).6(8)). Complexes 4 and 5 contain 2D racemic layers and (6,3)-honeycomb layers, respectively, both of which are combined into 3D supramolecular structures through pi-pi packing interactions of 2,2'-bpy. The structure of complex 6 is a 2D network formed by 4,4'-bpy bridging 1D tubes, which consist of metal atoms and enantiomers of L. These layers are connected through hydrogen bonds to give the final 3D porous supramolecular framework of 6. Complex 7 is a 3D MOF with novel (3,4,5)-connected (6(3))(4(2).6(4))(4(2).6(6).8(2)) topology. The thermal stability of these compounds was also investigated.
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Ácidos Carboxílicos/química , Cristalografía por Rayos X , Concentración de Iones de Hidrógeno , Ligandos , Conformación Molecular , Estereoisomerismo , Zinc/químicaRESUMEN
Luminescent acentric and homochiral coordination compounds, which possess new topological networks, multiple helical structures and NLO properties, have been generated through the control of a versatile asymmetric ligand as well as inorganic anions, and this suggests a new protocol for preparing acentric and chiral materials.
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Triazoles/química , Ligandos , Estructura Molecular , EstereoisomerismoRESUMEN
Two 3D Zn(II) and Pb(II) isophthalates, [Zn(ip)]n (1) and [Pb4(mu4-O)(ip)3(H2O)]n (2) (H2ip = isophthalic acid), have been prepared under hydro(solvo)thermal conditions and characterized by single-crystal X-ray diffraction. The two complexes crystallize in different space groups (P4(3)2(1)2 for 1 and P2(1)/c for 2) and have different bridging modes of the ip ligand. The 3D framework of 1 is constructed by the interconnection of ZnO4 polyhedra via ip ligands, which represents a chiral net with PtS-type topology. In contrast, complex 2 is formed by the combination of Pb4O-cluster secondary building units and has a novel (3.4.5)(3(2).4(5).5(6).6(7).7(2)) topology, which is the first ever example of a (3,7)-connected net. Complex 1 displays a second harmonic generation efficiency of about 1.5 times that of KH2PO4. Optical properties and thermal stabilities of the two complexes have been studied. Additionally, the calculations of band structure and density of states of 1 have also been performed with the density functional theory method.
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A new organic cation templated Zn(II) complex (Et3NH)[Zn4(ip)3(bta)3] (, ip = isophthalate, Hbta = benzotriazole) which consists of plate-like Zn4(bta)3 units bridged by ip ligands is reported; it is the first example of a 6-connected uninodal {3(3).5(9).6(3)}-lcy net which has never been observed previously in MOFs but has been theoretically anticipated.