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1.
Nat Commun ; 12(1): 781, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536416

RESUMO

After complete spinal cord injuries (SCI), spinal segments below the lesion maintain inter-segmental communication via the intraspinal propriospinal network. However, it is unknown whether selective manipulation of these circuits can restore locomotor function in the absence of brain-derived inputs. By taking advantage of the compromised blood-spinal cord barrier following SCI, we optimized a set of procedures in which AAV9 vectors administered via the tail vein efficiently transduce neurons in lesion-adjacent spinal segments after a thoracic crush injury in adult mice. With this method, we used chemogenetic actuators to alter the excitability of propriospinal neurons in the thoracic cord of the adult mice with a complete thoracic crush injury. We showed that activating these thoracic neurons enables consistent and significant hindlimb stepping improvement, whereas direct manipulations of the neurons in the lumbar spinal cord led to muscle spasms without meaningful locomotion. Strikingly, manipulating either excitatory or inhibitory propriospinal neurons in the thoracic levels leads to distinct behavioural outcomes, with preferential effects on standing or stepping, two key elements of the locomotor function. These results demonstrate a strategy of engaging thoracic propriospinal neurons to improve hindlimb function and provide insights into optimizing neuromodulation-based strategies for treating SCI.


Assuntos
Dependovirus/genética , Membro Posterior/fisiopatologia , Locomoção/fisiologia , Neurônios/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Animais , Antipsicóticos/administração & dosagem , Clozapina/administração & dosagem , Clozapina/análogos & derivados , Vetores Genéticos/genética , Membro Posterior/inervação , Locomoção/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia
2.
Bioresour Technol ; 323: 124630, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33418348

RESUMO

A novel layered double hydroxide (LDH)-orange peel (OP) biochar/sodium alginate (SA) (LBSA) synthetic material was prepared as an immobilized carrier for Acinetobacter sp. FYF8 to improve the removal of nitrogen and phosphorus in the bioreactor. Results demonstrated that under optimum conditions, the nitrate and phosphate removal efficiency reached 95.32 and 86.11%, respectively. The response surface methodology was used to illustrate the adsorption properties of the material and obtained optimal conditions for the removal of nitrate. The adsorption kinetics and isotherm were well fitted with the pseudo-second-order and Langmuir isotherm model, respectively, indicating that the adsorption process was mainly controlled by chemical adsorption and was favorable. Moreover, the morphology and composition of LBSA immobilized bacteria were analyzed and the mechanism of removing nitrate and phosphate was the synergistic effect of biological metabolism and adsorption. Community structure analysis and microbial distribution showed that FYF8 might was the dominant strain in bioreactors.


Assuntos
Nitratos , Poluentes Químicos da Água , Adsorção , Alginatos , Materiais Biocompatíveis , Reatores Biológicos , Carvão Vegetal , Hidróxidos , Cinética
3.
Bioresour Technol ; 323: 124608, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33421833

RESUMO

Pseudomonas sp. HXF1, a strain capable of heterotrophic nitrification, aerobic denitrification (HNAD), and biomineralization was identified and employed for the simultaneous removal of ammonia nitrogen (NH4+-N) and fluoride (F-). It removed 99.2% of NH4+-N without accumulation of nitrous nitrogen (NO2--N) and nitrate nitrogen (NO3--N), while removed 87.3% of F-. Response surface methodology (RSM) was used to study the best removal conditions for NH4+-N and F-. The results of nitrogen balance experiments with NH4Cl, NaNO2, and NaNO3 as single nitrogen sources and amplification experiments of denitrification genes proved that the bacterial strains may remove NH4+-N through HNAD. The experimental results of Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffractometer (XRD) indicated that the way of F- removal may be adsorption and co-precipitation. The results demonstrated that the strain HXF1 has great potential in the biological denitrification and F- removal of groundwater.


Assuntos
Água Subterrânea , Nitrificação , Aerobiose , Amônia , Biomineralização , Desnitrificação , Fluoretos , Processos Heterotróficos , Nitritos , Nitrogênio , Pseudomonas
4.
Chemosphere ; 273: 129667, 2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33485132

RESUMO

The coexistence of F-, Ca2+, nitrates, and other pollutants in water body has aroused widespread concern. In this research, a novel quartz sand biofilm reactor was established, aiming to study the key factors of different carbon to nitrogen (C/N) ratios (5:1, 4:1, and 3:1), initial Ca2+ concentration (180 mg L-1, 144 mg L-1, and 108 mg L-1), and hydraulic retention time (HRT) (4 h, 6 h, and 8 h) on simultaneous Ca2+ precipitation, F- removal, and denitrification. Results showed that the removal efficiencies of Ca2+, F-, and nitrate were 55.04%, 82.64%, and 97.69% under the low C/N ratio of 3:1, initial Ca2+ concentration of 180 mg L-1, and HRT of 8 h. 3-D Excitation-Emission Fluorescence Spectroscopy (3-D EEM) demonstrates that extracellular polymeric substances (EPS) was generated during the growth metabolism. Scanning Electron Microscopy (SEM) and X-ray diffractometer images showed that Ca2+, F- removed in the form of CaCO3, Ca5(PO4)3F and CaF2 under Acinetobacter sp. H12 induction. Moreover, high-throughput sequencing results display that the biomineralized bacteria Acinetobacter sp. H12 exerted great influence in the bioreactor. This research will underpin the practical use of multiple pollutants such as F- and Ca2+ wastewater under the different C/N ratios.

5.
Bioresour Technol ; 325: 124709, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33482476

RESUMO

This study aimed to clarify the facilitation by humic acid (HA) fractions (>100, 100-50, 50-30, 30-10, 10-3 and < 3 kDa), as well as their variable effect on denitrification of strain YSF15 under low carbon-nitrogen ratio and nitrate conditions. All HA fractions with 7 mg L-1 were able to accelerate nitrate removal by strain YSF15 and the role of carbon source was inconspicuous. The molecular weight (MW) < 3 kDa was the best promoter for denitrification, with the efficiency (91.32%) far exceeding the control (43.27%), resulting in more stable oxidation-reduction potential, higher nutrients utilization and electron transport activity, more compact protein structure in extracellular polymeric substances and the production of endogenous HA. Each HA fraction could change the bio-products and denitrification activity of strain YSF15. This study sheds light on the facilitation of HA in denitrification from the perspective of MW, implying the potential effect of HA on denitrifying bacteria in community.


Assuntos
Produtos Biológicos , Desnitrificação , Reatores Biológicos , Substâncias Húmicas , Peso Molecular , Nitratos , Nitrogênio/análise
6.
J Hazard Mater ; 406: 124748, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33310318

RESUMO

Biosynthetic crystals (BC) were prepared through microbially induced calcium carbonate precipitation (MICP) for fluoride (F-) removal from the groundwater. Batch experiments were conducted to evaluate the fluoride adsorption capacity and the impacts of critical factors (organic matter, pH, initial fluoride concentration and BC dosage) on defluorination efficiency of BC. The maximum adsorption amount and defluorination efficiency were recorded as 5.10 mg g-1 and 98.24%, respectively. The adsorption kinetics and isotherms studies showed that pseudo-second-order kinetic model and Freundlich isotherm model were best fitting to the reaction. Adsorption thermodynamic parameters indicated a spontaneous, endothermic and thermodynamically favorable adsorption process. Moreover, the mechanism of F- removal by BC was further analyzed by SEM, XPS, XRD and FTIR. The method can cope with the problem of applying the external organic substances in MICP, and avoid the microbial safety risk in the effluent. As an economically and environmentally friendly adsorbent, BC can be used for F- removal from groundwater.

7.
Bioresour Technol ; 321: 124447, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33302007

RESUMO

In the current research, a novel bioreactor composed of porous polymer carriers and iron-carbon (PPC@FeC) was established through bacterial immobilized technology. The influence of key factors was studied on the nitrate removal performance of the PPC@FeC bioreactor. The experimental results showed that the highest removal rate of nitrate (7.33 mg L-1 h-1) can be obtained with short hydraulic retention times (HRT = 2.0 h) and low carbon-to-nitrogen ratio (C/N = 2.0). The results of high-throughput sequencing revealed that Zoogloea sp. L2 was the dominant strain in bioreactor responsible for nitrate removal. Moreover, the SEM and XRD analyses elucidated that Fe2O3 was the final product produced by the interaction of FeC and strain L2. These findings showed that the PPC@FeC bioreactor successfully combined micro-electrolysis and biological denitrification, which exhibited great potential in removing nitrate effectively from wastewater under low C/N ratio and short HRT conditions.

8.
J Hazard Mater ; : 124414, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33243652

RESUMO

The co-contamination of groundwater with nitrate (NO3--N) and manganese (Mn(II)) is a global issue that needs to be efficiently remediated. In this research, a novel denitrifying and manganese-oxidizing strain HY129 was isolated from the sediments sample of a drinking water and identified as Cupriavidus sp. HY129. The remediation ability of strain HY129 regarding the nitrate and Mn(II) pollution were investigated. The removal efficiency of nitrate and Mn(II) were 99.81% (0.229 mgL-1 h-1) and 87.24% (0.233 mgL-1 h-1) in bacterial culture after 72 h, respectively. Moreover, the addition of Mn(II) significantly enhanced the denitrification process, while excessive concentration of Mn(II) caused more NO2--N accumulation. The impacts of adsorption and oxidation activity on Mn(II) removal were investigated. Protein in extracellular polymeric substance (EPS) which produced in the Mn-oxidizing process was speculated to be the main cause of extracellular adsorption of Mn(II). Characterization of biogenic manganese oxides (BMO) confirmed the formation of high-valent manganese and the trapping experiment with sodium pyrophosphate (NaPP) demonstrated the existence of Mn(III)-intermediates. Furthermore, multicopper oxidase gene amplification provided evidence for the molecular biology of Mn(II) oxidation by strain HY129.

10.
Bioresour Technol ; 320(Pt A): 124280, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33120060

RESUMO

The main purpose of this study is to isolate and purify oligotrophic denitrifying bacteria, Acinetobacter sp. FYF8, so as to study the denitrification capacity and characteristics in response to oligotrophic ecosystem. The RSM showed that the best denitrification efficiency was 97.90% under 7.58 pH, 20.69 °C temperature, and 2.83 C/N ratio. Nitrogen balance experiments showed that the nitrogen gas conversion ratio was 39.88, 68.85, and 78.79% at 2.0, 2.5, and 3.0 C/N ratio, respectively. According to 3D-EEM, tyrosine, tryptophan and aromatic protein were the metabolites produced by strain FYF8. The concentration of polysaccharide (PS) and proteins (PN) in different types of extracellular polymeric substances (EPS) and the variation trend were quantitatively studied. Different functional groups such as CH2, C = O, and C-O-C was characterized by FTIR. These findings indicated that the denitrification strategy of strain FYF8 was related to EPS, which might be a reserve carbon storage in carbon scarcity.

11.
J Hazard Mater ; : 124255, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33092874

RESUMO

The removal properties and mechanisms of fluoride (F-) and nickel (Ni2+) were studied by biomineralizing bacteria (Acinetobacter sp. H12). The results showed that the removal ratio of F-, Ca2+ and Ni2+ reached 75% (0.031 mg·L-1·h-1), 84.96% (2.123 mg·L-1·h-1), and 56.67% (0.024 mg·L-1·h-1) after 72 h, respectively. The removal ratio of nitrate (NO3-) reached 100% (0.686 mg·L-1·h-1) after 24 h. SEM and XRD images indicated that bioprecipitation of CaF2, Ca5(PO4)3F, Ca5(PO4)3(OH), NiCO3, CaCO3 and Ni were formed, and some of these precipitation used bacteria as nucleation sites to form biological crystal seeds. N2 was the primary product in gas chromatography analysis. Meanwhile, both the fluorescence spectroscopy and fourier transform near-infrared spectroscopy analysis proved that strain H12 had good ability to remove fluoride and nickel ions simultaneously.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32949365

RESUMO

To date, biogenic metals have opened up a window for new applications in adsorption of contaminants. But there is still little attention to be paid in the removal of tetracycline (TC) by biogenic iron precipitation (BIP). In this paper, the BIP, from iron-based mixotrophic denitrification batch reactor, was estimated for its adsorption property of TC under various parameters to simulate the behavior in aquatic environment. The maximum adsorption capacity for TC was 195.336 mg g-1. Analyses of spectrum verified the existence of Fe3O4 and FeOOH in BIP, which was the main reason for the removal of TC. The adsorption kinetic and isotherm of TC were well fitted to Elovich and Langmuir isotherm models, respectively, indicating that the adsorption process was mainly controlled by chemical adsorption. Furthermore, we proposed a potential mechanism of adsorption: a combination of cation-π, hydrogen bonding (H-bonding), and electrostatic interaction. Additionally, the activation experiment showed that BIP could enhance the degradation of TC (more than 98.00% removal within 1.0 h) by advanced oxidation process (AOP), due to the existence of FeOOH and Fe3O4. Considering its effectiveness in both adsorption and activation performance, BIP is highlighted as an economical and eco-friendly material for TC removal and offers a promising method to resolve sludge disposal in biological treatment of iron-rich groundwater.

13.
Bioresour Technol ; 314: 123733, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32619805

RESUMO

This paper aims to determine the denitrification strategies of strain YSF15 in carbon scarcity condition from novel view of organic nitrogen, soluble microbial products (SMP) and extracellular polymeric substances (EPS). The batch tests demonstrated that strain YSF15 could achieve complete denitrification at C/N of 3.0. The conversion ratio of nitrogen gas accounted for 89.03%, 85.29% and 82.95% among total nitrogen in C/N systems from 3.0 to 5.0, respectively, indicating denitrification instead of assimilation was the major contribution to nitrogen removal. C/N could affect composition and content of organic nitrogen, SMP and EPS. The biodegradability of EPS was better than SMP, whereas polysaccharide (PS) likely correlated with nitrogen removal, predating the protein (PN). These results implied high biodegradability of EPS and more electron donors for denitrification both improved denitrification capacity of strain YSF15, which revealed the potential contribution of bacterium with production of biodegradable SMP or EPS in biological treatment process.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Nitrogênio , Reatores Biológicos , Carbono , Desnitrificação , Esgotos
14.
Bioresour Technol ; 312: 123565, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32454439

RESUMO

Coexistence of multiple pollutants such as antibiotic, nitrate and heavy metal has received increasing attention resently. In this study, the functions of Pseudomonas sp.H117 on the removal of tetracycline(TC), nitrate and Mn(II), and biological materials (BMO(biogenic manganese oxides), MBMO(magnetic BMO)) on the removal of TC were investigated. Strain H117 showed higher TC removal efficiency of 68.86% (0.071 mg·L-1·h-1) within 96 h. Meanwhile, NO3-N and Mn(II) achieved high removal efficiency of 100% (0.211 mg·L-1·h-1) and 64.64% (0.265 mg·L-1·h-1), respectively. Furthermore, trapping experiments testified that Mn(III) intermediate formed during the biological manganese oxidation process, which contribute to the TC degradation. 91.29% and 96.63% of TC removal efficiency within 12 h were achieved by BMO and MBMO. Moreover, XPS, FTIR spectra, kinetics analysis and adsorption isotherms elucidated Mn(III) oxidation, chemical adsorption and ligand exchange reactions contribute to the removal of TC by biomaterials.


Assuntos
Materiais Biocompatíveis , Pseudomonas , Adsorção , Antibacterianos , Compostos de Manganês , Oxirredução , Óxidos , Tetraciclina
15.
Environ Sci Pollut Res Int ; 27(22): 28348-28359, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32415452

RESUMO

The ecological toxicity and potential risks of heavy metals that coexist with nitrates in wastewater have aroused public attention. This study developed an immobilized Fe3O4@Cu/PVA mixotrophic reactor (Fe3O4@Cu/PVA-IMR) to investigate the effect of different Mn (II) concentrations (10 mg L-1, 50 mg L-1, and 90 mg L-1), Cd (II) concentrations (10 mg L-1, 20 mg L-1, and 30 mg L-1), and hydraulic retention time (HRT) (6 h, 8 h, and 10 h) on simultaneous nitrate, Cd (II), and Mn (II) removal. Using the advanced modified biomaterial Fe3O4@Cu/PVA as carrier to embed bacteria, the performance of the reactor was further improved. The surface morphology of Fe3O4@Cu/PVA was characterized by SEM as a rough surface three-dimensional skeleton structure. When the HRT was 10 h, Mn (II) and Cd (II) concentrations were 40 mg L-1 and 10 mg L-1, respectively, indicating that the immobilized Pseudomonas sp. H117 with Fe3O4@Cu/PVA achieved the highest nitrate, Cd (II), and Mn (II) removal efficiencies of 100% (1.64 mg L-1 h-1), 98.90% (0.92 mg L-1 h-1), and 92.26% (3.58 mg L-1 h-1), respectively. Compared with a reactor without Fe3O4@Cu/PVA addition, the corresponding removal ratio increased by 22.63%, 7.09%, and 15.96%. Gas chromatography (GC) identified nitrogen as the main gaseous product. Moreover, high-throughput sequencing showed that Pseudomonas sp. H117 plays a primary role in the denitrification process.


Assuntos
Microbiota , Nitratos , Materiais Biocompatíveis , Reatores Biológicos , Cádmio , Desnitrificação , Álcool de Polivinil
17.
Nanomaterials (Basel) ; 9(4)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974787

RESUMO

Graphene has attracted attention in the material field of functional microcapsules because of its excellent characteristics. The content and state of graphene in shells are critical for the properties of microcapsules, which are greatly affected by the charge adsorption equilibrium. The aim of this work was to investigate the effect of pH value on the microstructure and properties of self-assembly graphene microcapsules in regard to chemical engineering. Microcapsule samples were prepared containing liquid paraffin by a self-assembly polymerization method with graphene/organic hybrid shells. The morphology, average size and shell thickness parameters were investigated for five microcapsule samples fabricated under pH values of 3, 4, 5, 6 and 7. The existence and state of graphene in dry microcapsule samples were analyzed by using methods of scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Fourier Transform Infrared Spectoscopy (FT-IR) and Energy Dispersive Spectrometer (EDS) were applied to analyze the graphene content in shells. These results proved that graphene had existed in shells and the pH values greatly influenced the graphene deposition on shells. It was found that the microcapsule sample fabricated under pH = 5 experienced the largest graphene deposited on shells with the help of macromolecules entanglement and electrostatic adherence. This microcapsules sample had enhanced thermal stability and larger thermal conductivity because of additional graphene in shells. Nanoindentation tests showed this sample had the capability of deforming resistance under pressure coming from the composite structure of graphene/polymer structure. Moreover, more graphene decreased the penetrability of core material out of microcapsule shells.

18.
Proc Natl Acad Sci U S A ; 116(13): 6397-6406, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30850520

RESUMO

Memory is stored in neural networks via changes in synaptic strength mediated in part by NMDA receptor (NMDAR)-dependent long-term potentiation (LTP). Here we show that a cholecystokinin (CCK)-B receptor (CCKBR) antagonist blocks high-frequency stimulation-induced neocortical LTP, whereas local infusion of CCK induces LTP. CCK-/- mice lacked neocortical LTP and showed deficits in a cue-cue associative learning paradigm; and administration of CCK rescued associative learning deficits. High-frequency stimulation-induced neocortical LTP was completely blocked by either the NMDAR antagonist or the CCKBR antagonist, while application of either NMDA or CCK induced LTP after low-frequency stimulation. In the presence of CCK, LTP was still induced even after blockade of NMDARs. Local application of NMDA induced the release of CCK in the neocortex. These findings suggest that NMDARs control the release of CCK, which enables neocortical LTP and the formation of cue-cue associative memory.


Assuntos
Colecistocinina/metabolismo , Potenciação de Longa Duração/fisiologia , Memória/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Córtex Auditivo/metabolismo , Comportamento Animal , Colecistocinina/genética , Estimulação Elétrica , Córtex Entorrinal/metabolismo , Feminino , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , N-Metilaspartato/metabolismo , Neocórtex/metabolismo , Neurônios/metabolismo , Ratos Sprague-Dawley , Receptor de Colecistocinina B/efeitos dos fármacos , Receptor de Colecistocinina B/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Sinapses/metabolismo
19.
Nanomaterials (Basel) ; 8(6)2018 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-29890764

RESUMO

Self-healing bituminous material has been a hot research topic in self-healing materials, and this smart self-healing approach is a promising a revolution in pavement material technology. Bitumen has a self-healing naturality relating to temperature, healing time, and aging degree. To date, heat induction and microencapsulation rejuvenator are two feasible approaches, which have been put into real applications. However, both methods have disadvantages limiting their practical results and efficiency. It will be an ideal method combining the advantages and avoiding the disadvantages of the above two methods at the same time. The aim of this work was to synthesize and characterize electrothermal self-healing microcapsules containing bituminous rejuvenator with graphene/organic nanohybrid structure shells. The microcapsules owned electric conductivity capability because of the advent of graphene, and realized the self-healing through the two approaches of heat induction and rejuvenation. The microcapsule shells were fabricated using a strength hexamethoxymethylmelamine (HMMM) resin and graphene by two-step hybrid polymerization. Experimental tests were carried out to character the morphology, integrity, and shell structure. It was found that the electric charge balance determined the graphene/HMMM microstructure. The graphene content in shells could not be greatly increased under an electrostatic balance in emulsion. X-ray photoelectron spectroscopy (XPS), Energy dispersive spectrometer (EDS), Transmission electron microscope (TEM) and Atomic force microscopy (AFM) results indicated that the graphene had deposited on shells. TGA/DTG tests implied that the thermal decomposition temperature of microcapsules with graphene had increased to about 350 °C. The thermal conductivity of microcapsules had been sharply increased to about 8.0 W/m²·K with 2.0 wt % graphene in shells. At the same time, electrical resistivity of microcapsules/bitumen samples had a decrease with more graphene in bitumen.

20.
Nanomaterials (Basel) ; 8(6)2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29795002

RESUMO

In recent decades, microcapsules containing phase change materials (microPCMs) have been the center of much attention in the field of latent thermal energy storage. The aim of this work was to prepare and investigate the microstructure and thermal conductivity of microPCMs containing self-assembled graphene/organic hybrid shells. Paraffin was used as a phase change material, which was successfully microencapsulated by graphene and polymer forming hybrid composite shells. The physicochemical characters of microPCM samples were investigated including mean size, shell thickness, and chemical structure. Scanning electron microscope (SEM) results showed that the microPCMs were spherical particles and graphene enhanced the degree of smoothness of the shell surface. The existence of graphene in the shells was proved by using the methods of X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). It was found that graphene hybrid shells were constructed by forces of electric charge absorption and long-molecular entanglement. MicroPCMs with graphene had a higher degradation temperature of 300 °C. Graphene greatly enhanced the thermal stability of microPCMs. The thermal conductivity tests indicated that the phase change temperature of microPCMs was regulated by the graphene additive because of enhancement of the thermal barrier of the hybrid shells. Differential scanning calorimetry (DSC) tests proved that the latent thermal energy capability of microPCMs had been improved with a higher heat conduction rate. In addition, infrared thermograph observations implied that the microPCMs had a sensitivity response to heat during the phase change cycling process because of the excellent thermal conductivity of graphene.

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