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Green engineering education is of great significance. The development of the chemical industry has a new direction under the background of engineering back to green engineering and chemistry. The undergraduate graduation chemical design is an important course for the comprehensive application of professional knowledge and bridging to the actual production, and also important support for the cultivation of chemical talent. This paper presents a case in which the improvement of ethyl acrylate process design can be selected as a topic of undergraduate graduation chemical design, which has both an industrial production process foundation that student can learn and engineering design innovation under the guidance of the green engineering concept. After the design study, the results show that the process design of ethyl acrylate supported by new clean catalysis and membrane separation technologies has been improved in reducing process complexity and improving environmental friendliness. Furthermore, the teaching result indicates that the process design reinforces students' green engineering thinking and provides a green engineering teaching format for chemical design. [Display omitted] • Green engineering principles and green chemical concept were integrated into undergraduate chemical design. • Process design for ethyl acrylate was improved. • It was developed that an undergraduate chemical design teaching model to train engineers for chemical production practice. [ABSTRACT FROM AUTHOR]

As an essential component of the ventilation system of nuclear facilities, filters have significant filtration performance for the safety of the environment and personnel. The metal fiber filter has excellent temperature resistance and can still maintain good filtration performance under fire conditions. In the filter design process, it is usually necessary to fold the metal fibrous fabric into a pleated structure to increase the filtration area and improve performance. A numerical simulation method is carried out on the filtration performance of the metal fiber filter, and the complex stacking structure inside the metal fibrous fabric is simulated using the porous zone. It is developed by combining the flow resistance and particle collection efficiency calculation program based on the structural parameters of the fibrous fabric with FLUENT software. The accuracy of the developed simulation method is validated with experimental data. The filtration performance of metal fiber pleated filters is further studied by this method. The results indicate that the influence of the pleat geometries on the collection efficiency of filters can be ignored. Brownian diffusion and interception play a dominant role in the filtration process. As the filtration velocity increases, the Brownian diffusion effect of particles is suppressed, this is the main reason for the decrease in filtration efficiency. With the same geometries, the resistance of rectangular pleats is always smaller than that of triangular pleats. With the same geometries, rectangular pleats have more uniform flow distribution than triangular pleats. • The filtration performance of pleated metal fiber filters with large pleat ratios was studied. • The flow distribution characteristics of rectangular and triangular pleats were compared. • The impact of filtration mechanisms on the efficiency of high-efficiency filters was explored. [ABSTRACT FROM AUTHOR]

Understanding the effects of urban morphology on urban environmental noise (UEN) at a regional scale is crucial for creating a pleasant urban acoustic environment. This study seeks to investigate how the urban morphology influences the UEN in the Shenzhen metropolitan region of China, by employing remote sensing and geographic information data. The UEN in this study consists of not only regional environmental noise (RN), but also traffic noise (TN). The experimental results reveal the following findings: 1) RN is positively correlated with the nighttime light intensity (NTL) and land surface temperature (LST) (p < 0.05). More interestingly, landscape composition and configuration can also significantly affect RN. For instance, urban vegetation can mitigate the RN (r = −0.411, p < 0.01). There is a reduced RN effect when fewer buildings exist in an urban landscape, in terms of the positive relationship between building density and RN (r = 0.188, p < 0.01). Given the same percentage of building area, buildings are more effective at reducing noise when they are distributed across the urban scenes, rather than being spatially concentrated (r = −0.205, p < 0.01). 2) TN positively relates to large (r = 0.520, p < 0.01) and small–medium (r = 0.508, p < 0.01) vehicle flow. In addition, vegetation along or near roads can alleviate the TN effect (r = −0.342, p < 0.01). TN can also become more severe in urban landscapes where there is higher road density (r = 0.307, p < 0.01). 3) Concerning the urban functional zones, traffic land is the greatest contributor to urban RN, followed by mixed residential and commercial land. The findings revealed by this research will indicate how to mitigate UEN. [ABSTRACT FROM AUTHOR]

Cytosolic Ca 2+ overload induced by N-methyl- d -aspartate (NMDA) is one of the major causes for neuronal cell death during cerebral ischemic insult and neurodegenerative disorders. Previously, we have reported that the cytokine interleukin-6 (IL-6) reduces NMDA-induced cytosolic Ca 2+ overload by inhibiting both L-type voltage-gated calcium channel (L-VGCC) activity and intracellular Ca 2+ store release in cultured cerebellar granule neurons (CGNs). Here we aimed to show that NMDA-gated receptor channels (i.e., NMDA receptors, NMDARs) are an inhibitory target of IL-6 via a mediation of calcineurin (CaN) signaling. As expected, IL-6 decreased NMDAR-mediated cytosolic Ca 2+ overload and inward current in cultured CGNs. The NMDAR subunits, NR1, NR2A, NR2B and NR2C, were expressed in CGNs. Blocking either of NR2A, NR2B and NR2C with respective antagonist reduced NMDA-induced extracellular Ca 2+ influx and neuronal death. Importantly, the reduced percentages in extracellular Ca 2+ influx and neuronal death by either NR2B or NR2C antagonist were weaker in the presence of IL-6 than in the absence of IL-6, while the reduced percentage by NR2A antagonist was not significantly different between the presence and the absence of IL-6. AG490, an inhibitor of Janus kinase (JAK), abolished IL-6 protection against extracellular Ca 2+ influx, mitochondrial membrane depolarization, neuronal death, and CaN activity impairment induced by NMDA. The CaN inhibitor FK506 reduced these IL-6 neuroprotective properties. Collectively, these results suggest that IL-6 exerts neuroprotection by inhibiting activities of the NMDAR subunits NR2B and NR2C (but not NR2A) via the intermediation of JAK/CaN signaling. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have shown an excitatory effect of histamine on neurons in two cerebellar nuclei, the fastigial nucleus and the interposed nucleus. Here we investigated action of histamine on the dentate nucleus (DN), another nucleus of the cerebellum, and provided more evidence for motor control by histamine via the cerebellum. Spontaneous unitary discharge of neurons in the DN was extracellularly recorded by use of cerebellar slice preparations. In total 79-recorded neurons, which were from 53 cerebellar slices, 67 neurons (84.8%) had an excitatory response to histamine stimulation, and the rest (15.2%) were not reactive. The histamine-induced excitation of the DN neurons was not blocked by low-Ca2+/high-Mg2+ medium, demonstrating that this effect of histamine was postsynaptic. Triprolidine, an antagonist of histamine H1 receptors, did not block the excitatory effect of histamine, but ranitidine, an antagonist for H2 receptors, blocked the excitatory response to histamine in a concentration-dependent manner. Further, histamine H1 receptor agonist 2-pyridylethylamine did not elicit any response of DN neurons, but H2 receptor agonist dimaprit had an excitatory action on the DN cells and this action was blocked by ranitidine. These results indicate that histamine excites cerebellar DN neurons via histamine H2 receptors. Since the DN receives hypothalamocerebellar histaminergic projections and plays a role in initiation and planning of somatic movement, the postsynaptic excitation of the DN neurons by histamine suggests the possibility that the initiation and planning of movement may be modulated by the histaminergic projections. [Copyright &y& Elsevier]

Abstract: Following some ideas of the quantum network coding protocol [Phys. Rev. A 76 (2007) 040301], we propose an efficient protocol to transmit two 2-level quantum states crossly over the butterfly network with two non-maximally entangled qubit pairs shared only between two senders. It is shown that both of the receivers can reestablish the initial states with a certain probability. And one classical bit communication can be saved at the bottleneck channel. Moreover, this protocol is generalized to the case of transmitting two multipartite entangled states. [Copyright &y& Elsevier]

Abstract: The reaction of AgClO4 with 2-naphthol-5-carboxylic acid (HL) and hexamethylenetetramine (hmt) in the presence of 2,6-dimethylpyridine afforded a photoluminescent three-dimensional (3D) AgI polymer {[Ag6(L)(μ3-hmt)2(μ4-hmt)2(ClO4)](ClO4)4(H2O)}∞ (1), which exhibited an unusual (3,4)-connected (6·7·8)2(4·6·7)2(4·7·8)2(72·8)2(62·7·83)(62·72·8·10) topological network (L =2-naphthol-5-carboxylate). Moreover, the luminescent properties of 1 have been briefly investigated. [Copyright &y& Elsevier]

This work investigates the effects and mechanisms of inhibiting TRPC6 (a non-selective cation channel) downregulation on rat astrocyte activation and proliferation following spinal cord injury (SCI) by suppressing AQP4 expression. We used HYP9 (TRPC6-specific agonist) and TGN-020 (AQP4-specific inhibitor) to explore the relationship between TRPC6 and AQP4 and their probable protective effects on SCI. Methods: In a rat SCI model, we randomly assigned female Sprague-Dawley rats into the following four groups: Sham, SCI, SCI+HYP9, and SCI+TGN-020. Western blotting and immunofluorescence staining were used to determine protein expression among groups following SCI. TUNEL and immunofluorescence staining were used to identify changes in the rate of apoptosis and the fraction of surviving neurons after SCI. The Basso-Beattie-Bresnahan open-field locomotor scale was used to identify changes in motor function after SCI. In vitro astrocyte scratch model, we first used the CCK8 assay to test the effects of varying doses of HYP9 or TGN-020 on astrocytes and then split the astrocytes into four groups: Con, Scratch, Scratch+HYP9, and Scratch+TGN-020. Western blotting and immunofluorescence were used to identify changes in the expression of target proteins. Results: In vivo and in vitro models, SCI dramatically decreased TRPC6 while considerably upregulating AQP4, glial fibrillary acidic protein (GFAP), and proliferating cell nuclear antigen (PCNA) expression. However, HYP9 or TGN-020 significantly suppressed activation of astrocytes, promoted neurons survival in the anterior horn of the spinal cords, and benefited the recovery of motor function in the hind limbs of rats following SCI. Interestingly, TRPC6 agonists dramatically suppressed AQP4 overexpression, indicating that the probable mechanism of HYP9 benefiting alleviation of SCI may be connected to AQP4 inhibition and astrocyte activation and proliferation reduction. Conclusion: we discovered for the first time that HYP9 inhibits astrocyte activation and proliferation by inhibiting AQP4 in SCI rats in vivo and in vitro models and that it preserves neuronal survival and functional recovery after SCI. • HYP9 (TRPC6-specific agonist) inhibits astrocyte activation and proliferation in SCI. • TGN-020 (AQP4-specific inhibitor) inhibits astrocyte activation and proliferation in SCI. • HYP9 inhibits AQP4 expression in SCI. • HYP9 or TGN-020 promote neuronal survival in the spinal cord and facilitate recovery of hindlimb motor function in rats after SCI. [ABSTRACT FROM AUTHOR]

Due to their unique physicochemical, optical and electrical properties, 2D semimetallic or semiconducting graphene has been extensively utilized to construct highly efficient heterojunction photocatalysts for driving a variety of redox reactions under proper light irradiation. In this review, we carefully addressed the fundamental mechanism of heterogeneous photocatalysis, fundamental properties and advantages of graphene in photocatalysis, and classification and comparison of graphene-based heterojunction photocatalysts. Subsequently, we thoroughly highlighted and discussed various graphene-based heterojunction photocatalysts, including Schottky junctions, Type-II heterojunctions, Z-scheme heterojunctions, Van der Waals heterostructures, in plane heterojunctions and multicomponent heterojunctions. Several important photocatalytic applications, such as photocatalytic water splitting (H 2 evolution and overall water splitting), degradation of pollutants, carbon dioxide reduction and bacteria disinfection, are also summarized. Through reviewing the important advances on this topic, it may inspire some new ideas for exploiting highly effective graphene-based heterojunction photocatalysts for a number of applications in photocatlysis and other fields, such as photovoltaic, (photo)electrocatalysis, lithium battery, fuel cell, supercapacitor and adsorption separation. [ABSTRACT FROM AUTHOR]