The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in *** isotopic signatures of ancient sediments have the potential to elucidate t...
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The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in *** isotopic signatures of ancient sediments have the potential to elucidate the evolutionary path of marine redox states and the biogeochemical nitrogen cycle within the water column of the Early Cambrian *** existing research on this topic has predominantly focused on South China,the exploration of other continental margins has been limited,leaving contradictory hypotheses *** this study,pairedδ^(15)N andδ^(13)C org analyses were performed on the Lower Cambrian successions from the Shiairike section(inner ramp)and Well Tadong 2(deep shelf/basin)in the northwestern and eastern Tarim Basin,*** data from the Shiairike section reveal a discernible shift in the operation of different nitrogen cycles for the black chert-shale unit,also referred to as the black rock series in Chinese literature,of the Yurtus Formation(Fortunian stage to lower Stage 3).Oscillatingδ^(15)N values for its lower part are suggestive of alternating anaerobic assimilation of NH 4+and denitrification/*** is likely attributed to a shallow,unstable chemocline consistent with the upwelling and incursion of deep,anoxic waters during a major *** contrast,aerobic nitrogen cycling,indicated by positiveδ^(15)N values of>2‰,dominated the upper part alongside a reduction in upwelling *** the other hand,theδ^(15)N signatures of Xishanbulake and Xidashan Formations of Well Tadong 2,which encompass a time interval from the Cambrian Fortunian Age to Age 4,are indicative of N_(2)fixation by diazotrophs as the major nitrogen *** two studied intervals,although not time-equivalent,exhibit separated states of nitrogen cycling at least during the deposition of the Yurtus black rock *** spatially different nitrogen cycling of the studied sections is compatible with a redox-stratified ocean dur
China vigorously is carrying out the construction of green building and ecological city during " The 12 th five-Year plan". Now,although the identification system of design and operation have been implemented in the e...
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China vigorously is carrying out the construction of green building and ecological city during " The 12 th five-Year plan". Now,although the identification system of design and operation have been implemented in the evaluation of green building,lacking of appropriate evaluation after use. The actual operation results of many buildings,which have got a green building logo,are not satisfied from the user 's perspective. In this paper,an evaluation method that combines the actual building energy consumption and users' satisfaction has been discussed,based on the post occupancy evaluation( POE) theory and the big data technology. Through the comparison and analysis of building objective operational metrics and users subjective feelings indicators,the green buildings' POE has been achieved. Finally,the study analyzes the assessed value of green building's POE from the three-time dimensions,short-term,medium-term and long-term. And the outlook of the direction is looking forward to the follow-up study.
Acellular nerve allografts conducted via chemical extraction have achieved satisfactory results in bridging whole facial nerve defects clinically,both in terms of branching a single trunk and in connecting multiple br...
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Acellular nerve allografts conducted via chemical extraction have achieved satisfactory results in bridging whole facial nerve defects clinically,both in terms of branching a single trunk and in connecting multiple branches of an extratemporal ***,in the clinical treatment of facial nerve defects,allogeneic donors are *** this experiment,we exposed the left trunk and multiple branches of the extratemporal segment in six rhesus monkeys and dissected a gap of 25 mm to construct a monkey model of a whole left nerve *** monkeys were randomly assigned to an autograft group or a xenogeneic acellular nerve graft *** the autograft group,the 25-mm whole facial nerve defect was immediately bridged using an autogenous ipsilateral great auricular nerve,and in the xenogeneic acellular nerve graft group,this was done using a xenogeneic acellular nerve graft with *** of facial symmetry,nerve-muscle electrophysiology,retrograde transport of labeled neuronal tracers,and morphology of the regenerated nerve and target muscle at 8 months postoperatively showed that the faces of the monkey appeared to be symmetrical in the static state and slightly asymmetrical during facial movement,and that they could actively close their eyelids *** degree of recovery from facial paralysis reached House-Brackmann grade II in both *** muscle action potentials were recorded and orbicularis oris muscles responded to electro-stimuli on the surgical side in each *** Gold-labeled neurons could be detected in the facial nuclei on the injured *** staining showed abundant neurofilament-200-positive axons and soluble protein-100-positive Schwann cells in the regenerated nerves.A large number of mid-graft myelinated axons were observed via methylene blue staining and a transmission electron *** together,our data indicate that xenogeneic acellular nerve grafts from minipigs are safe and effec
A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2'- formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizacti...
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A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2'- formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizaction using Ba2+ as template. The macrocycle 3 was further reduced giving saturated macrocycle 4. The structures of 3 and 4 were characterized by elemental analysis, ~H NMR, IR, and MS spectra, and their structures were determined via single crystal X-ray diffraction studies. X-ray diffraction analysis revealed that the macrocyclic compound 3 has a folded conformation, and the corresponding reduced product 4 adopts a twisted and folded conformation due to its flexible nature. ~ 2013 bi-Xue zhu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
In the present study, we carried out trace element analyses of black shales of the Edia- caran Doushantou Formation from two sections (Jiulongwan, Baiguoyuan) in Hubei Province, South China. Mo-U characteristics of ...
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In the present study, we carried out trace element analyses of black shales of the Edia- caran Doushantou Formation from two sections (Jiulongwan, Baiguoyuan) in Hubei Province, South China. Mo-U characteristics of black shales from the two sections and compiled Mo-U data of Dou- shantuo black shales from sections of a variety of sedimentary facies described the temporal/spatial variability in the redox conditions of paleo-seawater during deposition of the Donshantuo Formation. Changes in Mo-U patterns of the Doushantuo Member II (DST2) shales of open marine environments are consistent with a shift from a predominately oxic to a predominately anoxic ocean during their deposition. Mo-U patterns of the DST2 black shales from intra-shelf sections reflect basin restriction may have happened in the intra-shelf basin and are compatible with the redox-stratified model of the intra-shelf basin. Mo-U patterns of black shales of the Doushantuo Member IV (DST4) reveal that the shales from intra-shelf sections have more pronounced Mo enrichment and more significant enrich- ment of Mo over U than the slope shales, indicating the operation of a Mn particulate shuttle in the intra-shelf basin. High Mo/TOC ratios of the DST4 at the intra-shelf sections, in combination with similar Mo-TOC patterns of the DST4 from both intra-shelf and slope sections, indicate the intra- shelf basin was well connected to the open ocean during deposition of the DST4.
The interference pattern of two Bose–Einstein condensates released from a double-well potential for different holding times is theoretically investigated using a decoupled two-mode Bose–Hubbard *** two coherently se...
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The interference pattern of two Bose–Einstein condensates released from a double-well potential for different holding times is theoretically investigated using a decoupled two-mode Bose–Hubbard *** two coherently separated condensates,the interference displays a periodic behavior,which is closely related to the atomic interaction.A remarkable parity effect is found in the interference *** certain holding times,the even/odd total number of atoms would result in different interference *** influences of different initial conditions on the evolution of interference and the observation of parity effects are discussed.
Facile synthesis of photocatalysts with highly dispersed metal centers is a high-priority target yet still a significant *** this work,a series of Co-C_(3)N_(4) photocatalysts with different Co contents atomically dis...
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Facile synthesis of photocatalysts with highly dispersed metal centers is a high-priority target yet still a significant *** this work,a series of Co-C_(3)N_(4) photocatalysts with different Co contents atomically dispersed on g-CaN4 have been prepared via one-step thermal treatment of cobalt-based metal-organic frameworks(MOFs)and urea in the *** to the highly dispersed and rich exposed Co sites,as well as good charge separation efficiency and abundant mesopores,the optimal 25-Co-C_(3)N_(4),in the absence of noble metal catalysts/sensitizers,exhibits excellent performance for photocatalytic C0_(2) reduction to CO under *** irradiation,with a high CO evolution rate of 394.4μmol·g^(-1)·h^(-1),over 80 times higher than that of pure g-C_(3)N_(4)(4.9μmol·g^(-1)·h^(-1)).In:addition,by this facile synthesis strategy,the atomically dispersed Fe and Mn anchoring on g-C_(3)N_(4)(Fe-C_(3)N_(4) and Mn-C_(3)N_(4))have been also obtained,indicating the reliability and universality of this strategy in synthesizing photocatalysts with highly dispersed metal *** work paves a new way to develop cost-effective photocatalysts for photocatalytic C0_(2) reduction.
The synthesis of cyclopolymers upon controlling the degree of macrocyclic polymerization,followed by the discovery of new properties has attracted increasing attention in supramolecular ***,a Schiff-base condensation ...
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The synthesis of cyclopolymers upon controlling the degree of macrocyclic polymerization,followed by the discovery of new properties has attracted increasing attention in supramolecular ***,a Schiff-base condensation method performed at room temperature was used to control the formation of[1+1]and[2+2]*** pure MeOH,the isomer[1+1]macrocycles were synthesized and organic particles such as dendritic,rods,and solid microspheres were directly precipitated from the reaction ***[1+1]macrocycles can be efficiently converted into their corresponding[2+2]macrocycles accompanied by the tunable morphology of the organic particles when n-hexane was added to the MeOH *** studies showed that these organic particles have potential application toward the selective removal of Cd^(2+)ions with different adsorption ability in MeOH solution.
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