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1.
Sensors (Basel) ; 24(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39123987

RESUMO

The agile remote sensing satellite scheduling problem (ARSSSP) for large-scale tasks needs to simultaneously address the difficulties of complex constraints and a huge solution space. Taking inspiration from the quantum genetic algorithm (QGA), a multi-adaptive strategies-based higher-order quantum genetic algorithm (MAS-HOQGA) is proposed for solving the agile remote sensing satellites scheduling problem in this paper. In order to adapt to the requirements of engineering applications, this study combines the total task number and the total task priority as the optimization goal of the scheduling scheme. Firstly, we comprehensively considered the time-dependent characteristics of agile remote sensing satellites, attitude maneuverability, energy balance, and data storage constraints and established a satellite scheduling model that integrates multiple constraints. Then, quantum register operators, adaptive evolution operations, and adaptive mutation transfer operations were introduced to ensure global optimization while reducing time consumption. Finally, this paper demonstrated, through computational experiments, that the MAS-HOQGA exhibits high computational efficiency and excellent global optimization ability in the scheduling process of agile remote sensing satellites for large-scale tasks, while effectively avoiding the problem that the traditional QGA has, namely low solution efficiency and the tendency to easily fall into local optima. This method can be considered for application to the engineering practice of agile remote sensing satellite scheduling for large-scale tasks.

2.
Opt Express ; 31(1): 248-264, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606964

RESUMO

An instrument named as Volume Scattering and Attenuation Meter (VSAM) is presented. The VSAM can simultaneously measure the attenuation coefficient and the volume scattering function (VSF) from 10° to 170° with an interval of 10° at 659 nm. Using ultrapure water and NCRM-traceable polystyrene microsphere beads, the VSAM was calibrated, and the conversion factor χbθ for estimating the backscattering coefficient from the backward VSF was obtained based on Mie theory in the laboratory. For χbθ, the average relative deviation was no more than 7.77% in the range of 100°-160° between the modeled result based on VSAM and the theoretical result by Boss. Subsequently, the VSAM and ECO-VSF3 were deployed in situ in Zhanjiang Bay. The backscattering coefficient and VSF at the same angles measured by the two instruments were quite consistent. Some remarkable changes in the shape and magnitude of the VSF profile at different stations were found, with land-based pollutants composing an important suspicious source of these changes.

3.
J Environ Manage ; 345: 118882, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37673009

RESUMO

Nowadays, with the scarcity of water resources, competition for water resources among different levels and water sectors is growing increasingly fierce. Furthermore, uncertainties are unavoidable in the water resources system. To address the aforementioned issues, a fuzzy max-min decision bi-level multi-objective interval programming model was proposed, which can not only focus on water conflicts at the same level or between different levels, but also pay attention to optimal allocation of water resources under uncertainty. The developed model was then applied to a case study in Wuwei City, Gansu Province, China, which selected fairness of water distribution and agricultural economic benefits as planning objectives. Based on the developed model, different water resources optimal allocation schemes under different representative hydrological years were provided. From the result, as representative hydrological years changed from wet (P = 25%) to dry (P = 75%), agricultural economic benefit and Gini coefficient of agriculture would vary from [35.19, 37.78] × 108 yuan to [31.12, 31.99] × 108 yuan and from [0.468, 0.429] to [0.505, 0.503], which indicates that as available water resources decrease, agricultural economic benefit would decrease and fairness of water distribution would also decrease. And the water distribution fairness of the upper bound water allocation scheme is higher than that of the lower bound water allocation scheme when in the same representative hydrological year. In addition, no matter what representative hydrological year, the results of the established bi-level programming model are always in the middle of the results of the upper and lower level individual objective, which means that the developed bi-level programming model has great advantage to deal with water competing conflict among different levels. Furthermore, based on the results of developed model, the reasonable water resources optimization schemes can be determined by the decision-makers when faced with multi-objective, bi-level and multiple uncertainties problems.


Assuntos
Alocação de Recursos , Recursos Hídricos , Incerteza , Agricultura , Água
4.
Mikrochim Acta ; 186(1): 46, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30610467

RESUMO

CeO2-encapsulated gold nanoparticles (AuNPs) were anchored to reduced graphene oxide (RGO/Au@CeO2) by an interfacial auto-redox reaction in a solution containing tetrachloroauric acid and Ce(III) on a solid support. The resulting material was placed on a glassy carbon electrode (GCE) and used as an electrochemical hydrazine sensor at trace levels. The electrocatalytic activity of the modified GCE towards hydrazine oxidation was significantly enhanced as compared to only RGO/CeO2, or CeO2-encapsulated AuNPs, or AuNPs loaded on CeO2 modified with RGO. This enhancement is attributed to the excellent conductivity and large surface area of RGO, and the strong interaction between the reversible Ce4+/Ce3+ and Auδ+/Au0 redox systems. The kinetics of the hydrazine oxidation was studied by electrochemical methods. The sensor, best operated at a peak voltage of 0.35 V (vs. saturated calomel electrode), had a wide linear range (that extends from 10 nM to 3 mM), a low detection limit (3.0 nM), good selectivity and good stability. It was successfully employed for the monitoring of hydrazine in spiked environmental water samples and to in-vitro tracking of hydrazine in cells with respect to its potential cytotoxicity. Graphical abstract CeO2-encapsulated gold nanoparticles anchored on reduced graphene oxide with the strong interaction between the reversible Ce4+/Ce3+ and Auδ+/Au0 reductions can be used for sensitive detection of hydrazine with detection limit of 3 nM and good selectivity in environmental and biological samples.


Assuntos
Técnicas Eletroquímicas/métodos , Grafite/química , Hidrazinas/análise , Nanopartículas Metálicas/química , Cério/química , Técnicas Eletroquímicas/normas , Eletrodos , Ouro , Limite de Detecção , Oxirredução , Óxidos
5.
Small ; 14(16): e1703338, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29356378

RESUMO

Development of efficient, affordable, and sustainable energy storage technologies has become an area of interest due to the worsening environmental issues and rising technological dependence on Li-ion batteries. Na-ion batteries (NIBs) have been receiving intensive research efforts during the last few years. Owing to their potentially low cost and relatively high energy density, NIBs are promising energy storage devices, especially for stationary applications. A fundamental understanding of electrode properties during electrochemical reactions is important for the development of low cost, high-energy density, and long shelf life NIBs. This Review aims to summarize and discuss reaction mechanisms of the major types of NIB electrode materials reported. By appreciating how the material works and the fundamental flaws it possesses, it is hoped that this Review will assist readers in coming up with innovative solutions for designing better materials for NIBs.

6.
Chemistry ; 21(50): 18309-15, 2015 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-26511473

RESUMO

An ultrafacile aluminum reduction method is reported herein for the preparation of blue TiO2 nanoparticles (donated as Al-TiO2 , anatase phase) with abundant oxygen deficiency for lithium-ion batteries. Under aluminum reduction, the morphology of the TiO2 nanosheets changes from well-defined rectangular into uniform round or oval nanoparticles and the particle size also decreases from 60 to 31 nm, which can aggressively accelerate the lithium-ion diffusion. Electron paramagnetic resonance (EPR) and positron annihilation lifetime spectroscopy (PALS) results reveal that plentiful oxygen deficiencies relative to the Ti(3+) species were generated in blue Al-TiO2 ; this effectively enhances the electron conductivity of the TiO2 . X-ray photoelectron spectrometry (XPS) analysis indicates that a small peak is observed for the Al-O bond, which probably plays a very important role in the stabilization of the oxygen deficiencies/Ti(3+) species. As a result, the blue Al-TiO2 possesses significantly higher capacity, better rate performance, and a longer cycle life than the white pure TiO2 . Such improvements can be attributed to the decreased particle size, as well as the existence of the oxygen deficiencies/Ti(3+) species.

7.
Biomed Mater ; 19(3)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38518364

RESUMO

The development of efficacious bone substitute biomaterials remains a major challenge for research and clinical surgical. Herein, we constructed triple helix recombinant collagen (THRC) -based hydrogels loading bone morphogenetic protein-2 (BMP-2) to stimulate bone regeneration in cranial defects. A series of in situ forming hydrogels, denoted as THRC-oxidized carboxymethylcellulose (OCMC)-N-succinyl-chitosan (NSC) hydrogels, was synthesized via a Schiff base reaction involving OCMC, THRC and NSC. The hydrogels underwent rapid formation under physiological pH and temperature conditions. The composite hydrogel exhibits a network structure characterized by uniform pores, the dimensions of which can be tuned by varying THRC concentrations. The THRC-OCMC-NSC and THRC-OCMC-NSC-BMP2 hydrogels display heightened mechanical strength, substantial biodegradability, and lower swelling properties. The THRC-OCMC-NSC hydrogels show exceptional biocompatibility and bioactivity, accelerating cell proliferation, adhesion, and differentiation. Magnetic resonance imaging, computed tomography and histological analysis of rat cranial defects models revealed that the THRC-OCMC-NSC-BMP2 hydrogels substantially promote new bone formation and expedite bone regeneration. The novel THRC-OCMC-NSC-BMP2 hydrogels emerge as promising candidates for bone substitutes, demonstrating substantial potential in bone repair and regeneration applications.


Assuntos
Proteína Morfogenética Óssea 2 , Regeneração Óssea , Colágeno , Hidrogéis , Animais , Ratos , Materiais Biocompatíveis , Substitutos Ósseos , Quitosana/química , Hidrogéis/química
8.
Phys Chem Chem Phys ; 15(16): 6080-7, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-23493908

RESUMO

Carbon hollow spheres were produced using a sustainable approach, i.e. hydrothermal carbonization, using monosaccharides as carbon precursors and silica nanoparticles as hard-templates. Hydrothermal carbonization is an eco-efficient and cost-effective route to synthesize nanostructured carbonaceous materials from abundant biomass-derived molecules. After further thermal treatment under an inert atmosphere and removal of the silica-based core by chemical etching, porous hollow spheres depicting 5-8 nm thin shells were obtained. Subsequently, carbon-sulfur composites were synthesized via a melt diffusion method and used as nanostructured composites for cathodes in lithium-sulfur (Li-S) cells. The morphology of the hollow spheres was controlled and optimized to achieve improved electrochemical properties. Both high specific energies and high specific powers were obtained, due to the unique nanostructure of the hollow spheres. These results revealed that using optimized carbonaceous materials, it is possible to design sustainable Li-S cells showing promising electrochemical properties.

9.
Langmuir ; 28(33): 12373-83, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22853745

RESUMO

Hydrothermal carbonization (HTC) is an aqueous-phase route to produce carbon materials using biomass or biomass-derived precursors. In this paper, a comprehensive physicochemical and textural characterization of HTC materials obtained using four different precursors, namely, xylose, glucose, sucrose, and starch, is presented. The development of porosity in the prepared HTC materials as a function of thermal treatment (under an inert atmosphere) was specifically monitored using N(2) and CO(2) sorption analysis. The events taking place during the thermal treatment process were studied by a combined thermogravimetric/infrared (TGA-IR) measurement. Interestingly, these inexpensive biomass-derived carbon materials show good selectivity for CO(2) adsorption over N(2) (CO(2)/N(2) selectivity of 20 at 273 K, 1 bar and 1:1 gas composition). Furthermore, the elemental composition, morphologies, degree of structural order, surface charge, and functional groups are also investigated.

11.
Oncol Rep ; 44(5): 1799-1809, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33000284

RESUMO

Galectin­3 is expressed in various tissues and plays an important role in the tumor microenvironment (TME). Galectin­3 has been found to be overexpressed in a variety of cancers and is associated with tumor progression and metastasis. Over the past decades, emerging evidence has suggested that the TME may induce galectin­3 expression to maintain cellular homeostasis and promote cell survival. Furthermore, galectin­3 regulates immune cell function to promote tumor­driven immunosuppression through several mechanisms. In the TME, intracellular and extracellular galectin­3 has different functions. In addition, it has been reported that galectin­3 is associated with glycolysis and mitochondrial metabolism in tumors, and it is involved in the regulation of relevant signaling pathways, thus promoting cancer cell survival via adapting to the TME. The aim of the present review was to summarize the current knowledge on galectin­3 production and its function in the TME, its effect on TME immunosuppression, its association with tumor metabolism and relevant signaling pathways, and to report common types of cancer in which galectin­3 is highly expressed, in order to ensure a comprehensive understanding of the critical effects of galectin­3 on tumor progression and metastasis.


Assuntos
Galectina 3/metabolismo , Tolerância Imunológica/imunologia , Neoplasias/imunologia , Microambiente Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Modelos Animais de Doenças , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Galectina 3/antagonistas & inibidores , Glicólise/efeitos dos fármacos , Glicólise/imunologia , Humanos , Tolerância Imunológica/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Metástase Neoplásica/imunologia , Metástase Neoplásica/prevenção & controle , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Pectinas/farmacologia , Pectinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Microambiente Tumoral/efeitos dos fármacos
12.
Nanomicro Lett ; 12(1): 141, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34138145

RESUMO

Lithium-sulfur batteries (LSBs) are considered as the next generation of advanced rechargeable batteries because of their high energy density. In this study, sulfur and CoxS electrocatalyst are deposited on carbon nanotube buckypaper (S/CoxS/BP) by a facile electrodeposition method and are used as a binder-free high-performance cathode for LSBs. Elemental sulfur is deposited on buckypaper by electrooxidation of a polysulfide solution (~ S62-). This approach substantially increased the current and time efficiency of sulfur electrochemical deposition on conductive material for LSBs. S/CoxS/BP cathode could deliver an initial discharge capacity as high as 1650 mAh g-1 at 0.1 C, which is close to the theoretical capacity of sulfur. At current rate of 0.5 C, the S/CoxS/BP has a capacity of 1420 mAh g-1 at the first cycle and 715 mAh g-1 after 500 cycles with a fading rate of 0.099% per cycle. The high capacity of S/CoxS/BP is attributed to both the homogeneous dispersion of nanosized sulfur within BP and the presence of CoxS catalyst. The sodium dodecyl sulfate (SDS) pretreatment of BP renders it polarity to bind polysulfides and thus facilitates the good dispersibility of nanosized sulfur within BP. CoxS catalyst accelerates the kinetics of polysulfide conversion and reduces the presence of polysulfide in the cathode, which suppresses the polysulfide diffusion to anode, i.e., the shuttle effect. The mitigation of the active material loss improves not only the capacity but also the cyclability of S/CoxS/BP.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117483, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493713

RESUMO

Heavy metal pollution has become an important issue threatening human health and the liver is a very important metabolic organ. Here, we use label-free Raman confocal imaging to study the alterations of the liver tissue after cadmium pollution. Raman imaging has been performed on 100µmx100µm liver tissues to study the distribution of important macromolecules and the average Raman spectrum of the entire region has been used to characterize and quantize the change of biochemical compositions in liver tissue. The poisoned livers displayed a significant decrease in the intensity of 748 cm-1, 1128 cm-1 and 1585 cm-1 bands of cytochrome C, in comparison to the control. The collagen peak at 1082 cm-1 is significantly higher than that of control, suggesting the increasing fibrosis of Cd liver tissues. To confirm the results, we selected a 30µmx15µm liver cell area for high-resolution Raman imaging. We observed a substantial increase of lipids and proteins at specific points of hepatocytes. The confocal Raman imaging of liver tissues provided a unique tool to better understand disease-induced changes in the biochemical phenotype of primary liver tissues. Our study provides valuable references as in vitro models for studying Cd accumulation and toxicity in human liver.


Assuntos
Intoxicação por Cádmio/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Análise Espectral Raman/métodos , Animais , Intoxicação por Cádmio/patologia , Modelos Animais de Doenças , Humanos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal/métodos
14.
J Biophotonics ; 12(12): e201900157, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407491

RESUMO

Cadmium (Cd) is a toxic heavy metal which is harmful to environment and organisms. The reabsorption of Cd in kidney leads it to be the main damaged organ in animals under the Cd exposure. In this work, we applied confocal Raman spectroscopy to map the pathological changes in situ in normal and Cd-exposed mice kidney. The renal tissue from Cd-exposed group displayed a remarkable decreasing in the intensity of typical peaks related to mitochondria, DNA, proteins and lipids. On the contrary, the peaks of collagen in Cd-exposed group elevated significantly. The components in each tissue were identified and distinguished by principal component analysis. Furthermore, all the biological investigations in this study were consistent with the Raman spectrum detection, which revealed the progression and degree of lesion induced by Cd. The confocal Raman spectroscopy provides a new perspective for in situ monitoring of substances changes in tissues, which exhibits more comprehensive understanding of the pathogenic mechanisms of heavy metals in molecular toxicology.


Assuntos
Cádmio/toxicidade , Rim/efeitos dos fármacos , Análise Espectral Raman , Animais , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
Neuroinformatics ; 16(3-4): 363-372, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29948843

RESUMO

The era of human brain science research is dawning. Researchers utilize the various multi-disciplinary knowledge to explore the human brain,such as physiology and bioinformatics. The emerging disease association prediction technology can speed up the study of diseases, so as to better understanding the structure and function of human body. There are increasing evidences that miRNA plays a significant role in nervous system development, adult function, plasticity, and vulnerability to neurological disease states. In this paper ,we proposed the novel improved collaborative filtering-based miRNA-disease association prediction (ICFMDA) approach. Known miRNA-disease associations can be viewed as a bipartite network between diseases and miRNAs. ICFMDA defined significance SIG between pairs of diseases or miRNAs to model the preference on the choices of other entities. The collaborative filtering algorithm is further improved by incorporating similarity matrices to enable the prediction for new miRNA or disease without known associations. Potential miRNA-disease associations are scored with the addition of bidirectional recommendation results with low computational cost. ICFMDA achieved a 0.9076 AUC of ROC curve in global leave-one-out cross validation, which outperformed the state-of-the-art models. ICFMDA is a compact and accurate tool for potential miRNA-disease association prediction. We hope that ICFMDA would be useful in future miRNA and brain researches,and achieve better understanding of the nervous system in molecular level, cellular level, cell change process, and thus can support the research of human brain.


Assuntos
Estudos de Associação Genética/métodos , Predisposição Genética para Doença/genética , Práticas Interdisciplinares/métodos , MicroRNAs/genética , Algoritmos , Predisposição Genética para Doença/epidemiologia , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Valor Preditivo dos Testes
16.
Sci Rep ; 8(1): 10281, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29980702

RESUMO

Fine-scale parameterizations based on shear and stratification are widely used to study the intensity and spatial distribution of turbulent diapycnal mixing in the ocean. Two well-known fine-scale parameterizations, Gregg-Henyey-Polzin (GHP) parameterization and MacKinnon-Gregg (MG) parameterization, are assessed with the full-depth microstructure data obtained in the North Pacific. The GHP parameterization commonly used in the open ocean succeeds in reproducing the dissipation rates over smooth topography but fails to predict the turbulence over rough topography. Failure of GHP parameterization over rough topography is attributed to the deviation of internal wave spectrum from the Garrett-Munk (GM) spectrum. The internal wave field over rough topography is characterized by energetic intermediate-scale and small-scale internal waves that are not described well by the GM model. The MG parameterization that is widely used in coastal environments is found to be successful in reproducing the dissipation rates over both smooth and rough topographies. The efficacy of GHP and MG parameterizations in evaluating the dissipation rates has been assessed. The result indicates that MG parameterization predicts the magnitude and variability of the dissipation rates better than the GHP parameterization.

17.
Int J Biol Macromol ; 91: 294-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27164494

RESUMO

The self-assembly of FtsZ, the bacterial homolog of tubulin, plays an essential role in cell division. Light scattering technique is applied to real-time monitor the in vitro assembly of FtsZ in Arthrobacter strain A3, a newly isolated psychrotrophic bacterium. The critical concentration needed for the assembly is estimated as 6.7µM. The polymerization of FtsZ in Arthrobacter strain A3 requires both GTP and divalent metal ions, while salt is an unfavorable condition for the assembly. The FtsZ polymerizes under a wide range of pHs, with the fastest rate around pH 6.0. The FtsZ from Arthrobacter strain A3 resembles Mycobacterium tuberculosis FtsZ in terms of the dependence on divalent metal ions and the slow polymerization rate, while it is different from M. tuberculosis FtsZ considering the sensitivity to salt and pH. The comparison of FtsZ from different organisms will greatly advance our understanding of the biological role of the key cell division protein.


Assuntos
Arthrobacter/química , Proteínas de Bactérias/química , Proteínas do Citoesqueleto/química , Luz , Espalhamento de Radiação , Mycobacterium tuberculosis/química , Especificidade da Espécie
18.
Nanoscale ; 7(4): 1501-9, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25500995

RESUMO

In this work, a series of hollow carbon nanospheres simultaneously doped with N and Fe-containing species are prepared by Fe(3+)-mediated polymerization of dopamine on SiO2 nanospheres, carbonization and subsequent KOH etching of the SiO2 template. The electrochemical properties of the hollow nanospheres as nonprecious-metal electrocatalysts for oxygen reduction reaction (ORR) are characterized. The results show that the hollow nanospheres with mesoporous N-doped carbon shells of ∼10 nm thickness and well-dispersed Fe3O4 nanoparticles prepared by annealing at 750 °C (Fe/N/C HNSs-750) exhibit remarkable ORR catalytic activity comparable to that of a commercial 20 wt% Pt/C catalyst, and high selectivity towards 4-electron reduction of O2 to H2O. Moreover, it displays better electrochemical durability and tolerance to methanol crossover effect in an alkaline medium than the Pt/C. The excellent catalytic performance of Fe/N/C HNSs-750 towards ORR can be ascribed to their high specific surface area, mesoporous morphology, homogeneous distribution of abundant active sites, high pyridinic nitrogen content, graphitic nitrogen and graphitic carbon, as well as the synergistic effect of nitrogen and iron species for catalyzing ORR.

19.
Nanoscale ; 7(48): 20777, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26584332

RESUMO

Correction for 'High-surface-area mesoporous TiO2 microspheres via one-step nanoparticle self-assembly for enhanced lithium-ion storage' by Hsin-Yi Wang et al., Nanoscale, 2014, 6, 14926-14931.

20.
Nanoscale ; 6(24): 14926-31, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25363569

RESUMO

Mesoporous TiO2 microspheres assembled from TiO2 nanoparticles with specific surface areas as high as 150 m(2) g(-1) were synthesized via a facile one-step solvothermal reaction of titanium isopropoxide and anhydrous acetone. Aldol condensation of acetone gradually releases structural H2O, which hydrolyzes and condenses titanium isopropoxide, forming TiO2 nanocrystals. Simultaneous growth and aggregation of TiO2 nanocrystals leads to the formation of high-surface-area TiO2 microspheres under solvothermal conditions. After a low-temperature post-synthesis calcination, carbonate could be incorporated into TiO2 as a dopant with the carbon source coming from the organic byproducts during the synthesis. Carbonate doping modifies the electronic structure of TiO2 (e.g., Fermi level, Ef), and thus influences its electrochemical properties. Solid electrolyte interface (SEI) formation, which is not common for titania, could be initiated in carbonate-doped TiO2 due to elevated Ef. After removing carbonate dopants by high-temperature calcination, the mesoporous TiO2 microspheres showed much improved performance in lithium insertion and stability at various current rates, attributed to a synergistic effect of high surface area, large pore size and good anatase crystallinity.

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