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Novel bamboo activated carbon (BAC) catalysts decorated with manganese oxides (MnOx) were prepared with varying MnOx contents through a facile one-step redox reaction. Due to the physical anchoring effect of the natural macropore structure for catalyst active components, homogeneous MnOx nanoparticles (NPs), and high specific surface area over catalyst surface, the BAC@MnOx-N (N = 1, 2, 3, 4, 5) catalyst shows encouraging adsorption and catalytic oxidation for indoor formaldehyde (HCHO) removal at room temperature. Dynamic adsorption and catalytic activity experiments were conducted. The higher Smicro (733 m2/g) and Vmicro/Vt (82.6%) of the BAC@MnOx-4 catalyst could facilitate its excellent saturated and breakthrough adsorption capacity (5.24 ± 0.42 mg/g, 2.43 ± 0.22 mg/g). The best performer against 2 ppm HCHO is BAC@MnOx-4 catalyst, exhibiting a maximum HCHO removal efficiency of 97% for 17 h without any deactivation as RH = 0, which is higher than those of other MnOx-based catalysts. The average oxidation state and in situ DRIFTS analysis reveal that abundant oxygen vacancies on the BAC@MnOx-4 catalyst could be identified as surface-active sites of decomposing HCHO into the intermediate species (dioxymethylene and formate). This study provides a potential approach to deposit MnOx nanoparticles onto the BAC surface, and this hybrid BAC@MnOx material is promising for indoor HCHO removal at room temperature.
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As the skeleton substances of lignocellulosic biomass cell wall and the precursor of biofuels production, the research on cellulose structure, an important natural biomarcromolecules, attracts great attention. Considering its in situ features and higher resolution, Raman spectroscopy has been used to investigate the structure of cellulose molecular chain and cellulose aggregation structure at multi-scale. In this paper, the configurations and corresponding parameters of two types of Raman spectroscopy (Dispersive Raman and FT-Raman) were compared. Subsequently, the utilization of Raman spectroscopy in cellulose micro-distribution, cellulose enzyme hydrolysis, cellulose chain orientation and deformation, cellulose crystallinity and polymorphic transformation was discussed in detail. Given the existing deficiencies of the Raman spectroscopy when used to investigate the natural cellulose, some suggestions were proposed in order to promote the application of Raman spectroscopy to the research of natural macromolecular.
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Density, which is closely relate with many physical and mechanical properties of bamboo, is one of the important indicators of bamboo material properties. Moreover, because of existing different moisture gradients in bamboo, the measured results of the density are different. Based on X-ray computed tomography (X-CT) technology, the divergent degree of the CT values of 7 different aged Moso bamboo was compared under oven-dried, air-dried and water-saturated conditions. Except for the 4-year-old and 10-year-old Moso bamboo, the CT values of other aged bamboos have minor differences with each other; the models for the measured CT values and the corresponding densities of Moso bamboo were respectively fitted under oven-dried, air-dried and water-saturated conditions. Meanwhile, the model was also fitted under different moisture gradients, which was composed by the measured CT values and the corresponding densities of Moso bamboo. Then the relations between the CT values andthe densitiesof 7 different aged Moso bamboo were systematically analyzed under single moisture content and three moisture gradients;the CT values were fitted under oven-dried condition, of which the radial positions are relative to the outer of Moso bamboo. According to the relation between the CT value and the density, the fitting curves explain the reasons for the radial density variations of 7 different aged Moso bamboo. Results show that the relations, which are fitted by the measured densities and the corresponding CT values of 7 different aged Moso bamboo under oven-dried, air-dried and water-saturated conditions, are good linear and the slopes of those models are approximate; the relation of the densities with the CT values for Moso bamboo is linear under different moisture gradients, moreover, which is rarely affected by moisture. The regression equation is: D=0.001 H+1.003 2, R2=0.968 3(D is the density, H is the CT value) and the determination coefficient of the validation model is: R2=0.974 3; there is no obvious variation between the densities of the inner and the outer, but not in middle part to 7 different aged Moso bamboo under oven-dried condition. To realize rapid detection on the densities of Moso bamboo under different moisture content, these results provide technical support and data reference. At the same time, X-ray computed tomography (X-CT) technology also puts forward a new feasible way for the further studies of bamboo material properties and structure.
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Structural organization of the plant cell wall is a key parameter for understanding anisotropic plant growth and mechanical behavior. Four imaging platforms were used to investigate the cell wall architecture of Miscanthus sinensis cv. internode tissue. Using transmission electron microscopy with potassium permanganate, we found a great degree of inhomogeneity in the layering structure (4-9 layers) of the sclerenchymatic fiber (Sf). However, the xylem vessel showed a single layer. Atomic force microscopy images revealed that the cellulose microfibrils (Mfs) deposited in the primary wall of the protoxylem vessel (Pxv) were disordered, while the secondary wall was composed of Mfs oriented in parallel in the cross and longitudinal section. Furthermore, Raman spectroscopy images indicated no variation in the Mf orientation of Pxv and the Mfs in Pxv were oriented more perpendicular to the cell axis than that of Sfs. Based on the integrated results, we have proposed an architectural model of Pxv composed of two layers: an outermost primary wall composed of a meshwork of Mfs and inner secondary wall containing parallel Mfs. This proposed model will support future ultrastructural analysis of plant cell walls in heterogeneous tissues, an area of increasing scientific interest particularly for liquid biofuel processing.
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Parede Celular/química , Parede Celular/ultraestrutura , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Transmissão/métodos , Poaceae/química , Poaceae/ultraestrutura , Análise Espectral Raman/métodos , Celulose/análise , Celulose/ultraestrutura , Microfibrilas/química , Microfibrilas/ultraestruturaRESUMO
The wood property and production process affect quality of Guqin. At the same time, Guqin shape with cavity layout relations to the improvement of Guqin technology and inheritance, so it's very important to get the internal cavity characteristics and parameters on the condition of non-destructive the structure of Guqin. The image of interior structure in Guqin was investigated by overall scanning based on non-destructive testing technology of computed tomography, which texture of faceplate, connection method between faceplate and soleplate and interior defects were studied. The three-dimensional reconstruction of Guqin cavity was achieved through Mimics software of surface rendering method and put the two-dimensional CT tomography images convert into three-dimensional, which more complete show interior structural form in Guqin, and finally the parameter of cavity dimensions was obtained. Experimental research shows that there is significant difference in Guqin interior structure between Zhong-ni and Luo-xia type, in which the fluctuation of the interior surfacein Zhong-ni type's is larger than that in Luo-xia type; the interior volume of Zhong-ni typeis less than that of Luo-xia type, especially in Guqin neck. The accurate internal information of Guqin obtained through the computed tomography (CT) technology will provide technical support for the Guqin manufacture craft and the quality examination, as well as provide the reference in the aspect of non-destructive testing for other traditional precious internal structure research.
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Density is one of the important physical indicators of bamboo, associated with its many physical and mechanical properties. The temporal and spatial variation of density in 2-5-year-old Dendrocalamus farinosus were measured using computed tomography (CT) technology. Scanning parameters were obtained through orthogonal design. The relationship of air-dry density (Y) and the corresponding CT values (X) was established and verified through regression analysis, which presents an approximate linear relationship between them. The linear equation is Y=0.001X+1.148. The radial and longitudinal variation of density was determined by the regression model. This study provides a new method to measure bamboo density efficiently and accurately, and also put forward a new thought to further study structure and characteristics of bamboo.
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Poaceae/crescimento & desenvolvimento , Tomografia Computadorizada por Raios X , Modelos Teóricos , Análise de Regressão , Análise Espaço-TemporalRESUMO
X-ray diffraction technology was used to rapidly predict variation in microfibril angle (MFA) in Dendrocalamus fari- X-ray diffraction technology was used to rapidly predict variation in microfibril angle (MFA) in Dendrocalamus farinosus. The results show that there is little variation in MFA with bamboo age from 2a to 5e, and MFA of 3a is at the maximum with the value of 8.521 degrees. The average value of MFA of 2a or 3a is greater than 4a or 5a with absolute differences less than 0.10 degrees. MFA of base, middle and upper position respectively are 8.499 degrees, 8.497 degrees and 8.483 degrees with coefficient of variation about 5%. There is an increasing tendency from the periphery to the inner of bamboo culms. Variance analysis indicates that MFA is highly sensitive to radial position, but insensitive to bamboo age and longitudinal position. The correlation coefficient of longitudinal strength and modulus of elasticity (MOE) is 0.57. MFA was responsible for 35% and 43% of the variation found in longitudinal strength and MOE respectively, which means MFA has a certain extent effect on mechanical properties.
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Microfibrilas/fisiologia , Poaceae/anatomia & histologia , Difração de Raios X , Análise de Variância , Resistência à TraçãoRESUMO
BACKGROUND/AIMS: To investigate the effects of K-ras siRNA on pancreatic cancer cells and the expression levels of GLI1, E-cadherin and vimentin in pancreatic cancer cells transfected with K-ras siRNA. METHODOLOGY: Ppancreatic cancer cells PANC-1 were transfected with K-ras siRNA. Growth inhibition ratio of the cells were measured by MTT assay, apoptosis was detected by flow cytometery, expression level of GLI1, E-cadherin and vimentin were detected by Western blot. RESULTS: The expression of K-ras protein was efficiently inhibited by K-ras siRNA in PANC-1 cells. The growth inhibition rates of the cells were significantly different to the control groups. Apoptosis rates were significantly different with that of control group. The expression of GLI1 was significantly down-regulated, E-cadherin was up-regulated, while vimentin was also down-regulated in K-ras siRNA transfected cells compared with that of control groups. CONCLUSIONS: Inhibiting K-ras signaling by K-ras siRNA can inhibit proliferation and induce apoptosis of pancreatic cancer cells, down-regulate GLI1's and vimentin's expression, and up-regulate E-cadherin's expression. Inhibiting K-ras signaling by K-ras siRNA may reduce epithelial to mesenchymal transition of pancreatic cancer cell PANC-1.
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Transição Epitelial-Mesenquimal , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/fisiologia , Proteínas ras/fisiologia , Apoptose , Caderinas/análise , Linhagem Celular Tumoral , Humanos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras) , Vimentina/análise , Proteínas ras/antagonistas & inibidoresRESUMO
Bamboo is a natural vascular bundle (VB) reinforced composite material used in more than 10 fields such as construction and furniture. The nodes in bamboo are crucial to its mechanical properties, but understanding of its performance is limited by lack of knowledge about the three-dimensional (3D) structure of the node. This work aimed to non-destructively identify the multi-dimensional characteristics of the VB in a bamboo branched node (BN) using X-ray microtomography (µCT). The VB was segmented from the BN using deep learning combined with the Watershed algorithm. The 3D model reconstruction and characterization of the VB were also conducted. It was found that the structure of VBs showed significant changes along the height of the BN. The VBs formed a complex 3D structure, VBs of the culm are connected with those of the branch, and the connectivity of the conducting tissue and fibers was 88.91% and 99.95%, respectively. The conducting tissue and the fibers had similar shapes but varying thicknesses, which enabled VBs to perform both water transport and mechanical support functions. The volumes fraction of parenchyma, fibers, and conducting tissue in the BN were 61.3%, 35.3%, and 3.4%, respectively, but the tissue proportion of the different heights of the BN varied from each other. The nodal ridge was a mechanical weak point of the BN, with a maximum fibers proportion of 43.8%. This study contributes to understanding the relationship of VBs between the branch and the culm. It provides a structural perspective for understanding the mechanical properties of BN and a theoretical basis for optimizing bamboo utilization efficiency.
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CT is widespread non-destructive detection technique for wood materials, and the density measurement is a key role during this application. In the present report, the use of CT for air-dry density measurement of wood and bamboo is described. The authors found that there were marked linear correlations between air-dry density (0.303-1.061 g x cm(-3)) of 24 kinds of woods and their respective CT value, as well as 25 kinds of lignin materials (including 24 kinds of woods and 1 kind of bamboo) and the CT value, both with correlation coefficient of 0.99, which belonged to the CT technological breakthrough for wood quantitative detection These research results show that CT is an appropriate way to measure density for wood and bamboo, and would provide technical support for CT used in the field of wood science research and wood processing.
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Bambusa , Tomografia Computadorizada por Raios X , Madeira , LigninaRESUMO
As a renewable biological macromolecule with aromatic structure, lignin can serve as matrix substance to maintain cell wall integrity and is regarded as the natural biomass recalcitrance. Substantial differences in the cell wall lignin topochemistry between opposite (Ow) and compression wood (Cw) trachieds in Pinus bungeana Zucc. were visualized during [Emim][OAc] pretreatment at room temperature. The ionic liqiuds treatment induced a more obvious wall swelling for highly lignified Cw tracheids than that of Ow, while dynamic Raman spectra analysis indicated the higher lignin and carbohydrates removal for Ow tracheids. Raman imaging further revealed that both lignin and carbohydrates were dissolved simultaneously within the middle lamella and secondary wall of Ow and pretreatment has little effects on Cw tracheids wall. Moreover, it was demonstrated that lignin composition was the key factor to affect the composition dissolution. In particular, lignin G-units were selectively removed from cell corner middle lamella (52.3 %) and secondary wall (62.0 %) of Ow tracheids. When cotton fiber, as a reference was treated under the same conditions, lattice conversion moving from cellulose I to II occurred. The findings confirmed the important role of lignin compostion in the dissolution behavior of carbohydrate dominant tracheids wall.
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Pinus , Madeira , Madeira/química , Lignina/química , Solubilidade , Pinus/química , Parede Celular/química , Celulose/químicaRESUMO
The morphological characteristics of fibers and vessels of six rattan species in Southern China were investigated to study the feasibility of predicting the lengths of fibers and vessels of rattan species with application of analytical technologies of near infrared spectroscopy (NIR). The results showed that the average lengths of fibers and vessels of six rattan species were from 1 229 to 1 917 mm and from 1 035 to 2 129 mm, respectively. The models of length of fiber and vessel were constructed by combining partial least square (PLS) and full cross-validation, and a good correlation between the length of fibers and the spectrum transformed by the first derivative was found within the spectral range of 350 - 2 454 nm, and the correlation coefficient (r(c) and r(p)) and standard error (SEC and SEP ) of calibration model and prediction model are 0.98, 0.85 and 70, 178 respectively, while a good correlation between the length of vessels and the spectrum transformed by the first derivative was found within the spectral range of 350-2 500 nm, the correlation coefficient (r(c) and r(p)) and standard error (SEC and SEP) of calibration and prediction model is 0.97, 0.80 and 101, 261 respectively. Their model parameters showed that NIR spectroscopic technique can rapidly and accurately predict the lengths of fibers and vessels of the six rattan species.
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Calamus , Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , China , Análise dos Mínimos QuadradosRESUMO
In order to find the relationships between the crystal size and the physical & mechanical properties, and to improve the levels of high value-added processing and utilizing for Chinese rattan resources, the daemonorops margaritae, Chinese unique rattan, was chosen as the research material, then the crystal size was measured and analyzed through the X-ray diffraction method before and after gamma-ray irradiation. The results show that the crystal width is in the range between 1.901 and 3.019 nm, and the average width is 2.403 nm. The crystal length is in the range between 4.118 and 28.824 nm with an average length of 10.907 nm. After irradiation, the width of daemonorops margaritae is in the range between 2.139 and 3.540 nm, and the average width is 2.569 nm, and the crystal length dramatically changes in the range between 5.765 and 38.432 nm with a mean of 15.530 nm. Both of the scope and the mean value of the crystal width and length increase after irradiation.
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In order to find out the properties and improve the levels of high value-added processing and utilization of Chinese rattan resources, the Daemonorops Margaritae, a Chinese unique rattan, was chosen as the research material, then the microfibril angles (MFA) & crystallinity index (CrI) were measured through the X-ray diffraction method, and the effects of gamma-ray irradiation upon the MFA & CrI were analyzed. The results show that the MFA of the cane varied from 33.4 degrees to 38.7 degrees with the average value of 36.1 degrees, and the MFA of the coretex were not larger than that of the core. The MFA were 36.2 and 35.8 degrees, 35.9 and 35.4 degrees, and 36.2 and 35.4 degrees before and after irradiation with a radiation dose rate of 2.5 x 10(3) Gy x h(-1) and radiation dose of 3, 9 and 15 kGy, and decreased 1.10%, 1.39% and 2.21% respectively compared with the former. The CrI was in the range of 24.8%-32.0%, and the average CrI was 28.6%. The CrI of coretex was larger than that of the core. Under the same radiation conditions, the CrI was 28.1% and 26.0%, 28.1% and 26.9%, and 28.5% and 27.1% before and after irradiation, and the latter decreased 7.58%, 4.34% and 4.70% respectively compared to the former. With the radiation dose of 3 kGy, the differences in CrI between with and without irradiation were most notable in the 0.001 level.
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Arecaceae/química , Difração de Raios X , Arecaceae/efeitos da radiação , Raios gamaRESUMO
Bamboo, a kind of forest resources only less important than wood, is especially easy to mildew during outdoor service. In this work, TiO2 sols were synthesized under low-temperature condition by sol-gel method. The crystalline TiO2 film with a diameter of approximate 40-90 nm was used to coat bamboo at low temperature. The TiO2 films were characterized by nuclear magnetic resonance spectrometer (NMR), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDAX). The effects of temperature on film crystal forms, its antibacterial, and mildew resistance properties were mainly investigated. The results showed that the modified bamboo in low temperature solution (20, 60 and 105 degrees C) was mainly covered with anatase nano TiO2 film. The nano-TiO2-modified bamboo maintained the natural wood color, texture and structure, and improved its anti-bacterial property from non-anti-bacterial to anti-Escherichia coli, and the bactericidal rate reached over 99%. Meanwhile its mildew resistance property increased over 10 times. So this method is expected to become the new way of functional improvement on bamboo, and has the reference meaning for the protection and improvement of wood and other biologic materials.
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Antibacterianos , Bambusa , Fungicidas Industriais , Nanopartículas Metálicas , Titânio , Escherichia coli , Difração de Raios XRESUMO
The lignin distribution in different anatomical regions of developing moso bamboo Phyllostachys pubescens f. lutea Wen was investigated by means of optical microscope and visible-light microspectrophotometry coupled with the Wiesner and Maule reaction. The lignin is widely distributed in different tissues, in which there is a difference in lignin content between different ages, tissues and anatomical regions. Guaiacyl lignin and Syringyl lignin unit can be found in cell wall of fibre, parenchyma and vessel. Lignin content of secondary wall, cell corner and compound middle lamellae of fibre increased gradually within 12 months, then almost remained in the same level or decreased slowly in the culms with an age from 12 to 78 months. The lignification rate in secondary wall, cell corner and compound middle lamellae of fibre changed with age until they reached a relative steady value. There is no regular variation in lignin content with different radial location of culms and different location in fibre strands within one age. The secondary wall, compound middle lamellae of parenchyma and vessel secondary wall lignified rapidly within 12 months, and then changed slowly.
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Lignina/análise , Poaceae/química , Parede Celular , Estruturas Vegetais , EspectrofotometriaRESUMO
This work aims to elucidate the effects and the potential underlying mechanisms of microRNA-216a-3p (miR-216a-3p) on the proliferation, migration, and invasion of gastric cancer (GC) cells. In this study, we revealed that the expression of miR-216a-3p was significantly elevated in GC tissues and cell lines. The different expression level of miR-216a-3p was firmly correlated with clinicopathological characteristics of GC patients. We next demonstrated that upregulation of miR-216a-3p could dramatically promote the ability of proliferation, migration, and invasion of GC cells using a series of experiments, whereas downregulation essentially inhibited these properties. Additionally, through bioinformatics analysis and biological approaches, we confirmed that runt-related transcription factor 1 (RUNX1) was a direct target of miR-216a-3p, and overexpression of RUNX1 could reverse the potential effect of miR-216a-3p on GC cells. Furthermore, mechanistic investigation using Western blot analysis showed that downregulation of RUNX1 by miR-216a-3p could stimulate the activation of NF-κB signaling pathway. In summary, this work proved that miR-216a-3p can promote GC cell proliferation, migration, and invasion via targeting RUNX1 and activating the NF-κB signaling pathway. Therefore, miR-216a-3p/RUNX1 could be a possible molecular target for innovative therapeutic agents against GC.
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Adenocarcinoma/patologia , Subunidade alfa 2 de Fator de Ligação ao Core/biossíntese , MicroRNAs/genética , NF-kappa B/biossíntese , Neoplasias Gástricas/patologia , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Invasividade Neoplásica/genética , Transdução de Sinais/genética , Neoplasias Gástricas/genéticaRESUMO
With no effective treatments available for most pancreatic cancer patients, pancreatic cancer continues to be one of the most difficult malignancies to treat. Oncolytic virus mediated-gene therapy has exhibited ubiquitous antitumor potential. In this study, we constructed a novel oncolytic vaccinia virus harboring the inhibitor of growth family member 4 gene (VV-ING4) to investigate its therapeutic efficacy alone or in combination with gemcitabine against pancreatic cancer cells in vitro and in vivo. ING4 expression was determined via quantitative real-time polymerase chain reaction (qPCR) and western blot. The cytotoxicity of VV-ING4 was measured using a cell proliferation assay. Both flow cytometry and western blot were applied to analyze the cell cycle and apoptosis. Furthermore, the combination inhibitory effect of VV-ING4 and gemcitabine was assessed using Chou-Talalay analysis in vitro and a BLAB/c mice model in vivo. We found that VV-ING4 significantly increases ING4 expression, displayed greater cytotoxic efficiency, and induced pancreatic cancer cell apoptosis and G2/M phase arrest. Additionally, the combination of VV-ING4 and gemcitabine synergistically effect in vitro and in vivo. Taken together, our data implicate VV-ING4 as a conceivable pancreatic cancer therapeutic candidate alone or in combination with gemcitabine.
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The core-shell structure of carbon encapsulated magnetic nanoparticles (CEMNs) displays unique properties. Enhancing the magnetization of iron core, in parallel, improving the encapsulation of carbon shell are the two major challenges in the synthesis of CEMNs. Inspired by efficient cellulose-dissolving system, carbon encapsulated magnetic nano-Fe3O4 particles (Fe3O4@C) with â¼10.0nm Fe3O4 cores and 1.9-3.3nm carbon shell, were successfully one-pot synthesized via a novel hydrothermal carbonization (HTC) process. The dissolving process in ionic liquids ([Emim]Ac and [Amim]Cl) completely cleaved the intra- and intermolecular H-bonds in cellulose, and favored the incorporation of Fe3O4 nanoparticles into the cellulose H-bonds systems during the regeneration process. Some stable linkages were formed in Fe3O4@C, taking Fe3O4 nanoparticles as a structure guiding agent. The morphology and properties of Fe3O4@C depended strongly on the type of carbon precursors and pyrolysis temperature. Well encapsulated nanostructure was obtained at HTC temperature 280°C, when [Emim]Ac-treated holocellulose was used as the carbon source. Meanwhile, the thickness of the amorphous shell and magnetization increased with HTC temperature. More importantly, a novel elements for understanding the growth mechanism for the Fe3O4@C composite under HTC conditions was proposed.