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全生物质单组份膨胀型阻燃剂的制备与性能研究实验设计 PKU
期刊论文 | 2024 , 41 (03) , 232-237 | 实验技术与管理
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Abstract :

该文以生物质材料作为原料制备了单组分膨胀型阻燃剂,并将其加入聚乳酸中制备了复合材料。实验结果表明,该阻燃剂能够显著提高聚乳酸的阻燃性能和抗熔滴性能,且热稳定性良好。该实验涉及高分子材料配方设计、成型加工、性能测试、结构表征等专业知识,可使学生掌握高分子材料阻燃机理,熟练使用相关仪器设备进行测试与分析,有利于他们提高综合运用知识的能力,并针对高分子材料与工程领域的复杂工程问题设计解决方案。

Keyword :

探索性实验 探索性实验 生物质 生物质 聚乳酸 聚乳酸 阻燃 阻燃

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GB/T 7714 靳艳巧 , 曹静 , 胡礼波 et al. 全生物质单组份膨胀型阻燃剂的制备与性能研究实验设计 [J]. | 实验技术与管理 , 2024 , 41 (03) : 232-237 .
MLA 靳艳巧 et al. "全生物质单组份膨胀型阻燃剂的制备与性能研究实验设计" . | 实验技术与管理 41 . 03 (2024) : 232-237 .
APA 靳艳巧 , 曹静 , 胡礼波 , 熊雷 . 全生物质单组份膨胀型阻燃剂的制备与性能研究实验设计 . | 实验技术与管理 , 2024 , 41 (03) , 232-237 .
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Research Progress of Chitosan-based Multifunctional Nanoparticles in Cancer Targeted Therapy SCIE
期刊论文 | 2024 , 31 (21) , 3074-3092 | CURRENT MEDICINAL CHEMISTRY
WoS CC Cited Count: 1
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Abstract :

Conventional tumor therapeutic modalities, such as radiotherapy, chemotherapy, and surgery, involve low tumor inhibition efficiency, non-targeted drug delivery, and side effects. The development of novel and practical nano-drug delivery systems (DDSs) for targeted tumor therapy has become particularly important. Among various bioactive nanoparticles, chitosan is considered a suitable candidate for drug delivery due to its non- toxicity, good biocompatibility, and biodegradability. The amino and hydroxyl groups of chitosan endow it with the diverse function of chemical modification, thereby improving its physical and biological properties to meet the requirements of advanced biomedical applications. Therefore, it is necessary to review the property and applications of chitosan-based materials in biomedicine. In this review, the characteristics of chitosan related to its applications are first introduced, and then the preparation and modification of chitosan-based nanoparticles, including the function tailoring of chitosan-modified nanoparticles, are demonstrated and discussed. Finally, the opportunities and challenges of chitosan-based nanomaterials in this emerging field are proposed from the perspective of the rational and systematic design for the biomedicine field.

Keyword :

biocompatibility biocompatibility cancer treatment cancer treatment Chitosan Chitosan nano-drug delivery systems (DDSs) nano-drug delivery systems (DDSs) nanoparticles nanoparticles targeted delivery targeted delivery

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GB/T 7714 Lai, Chunmei , Lin, Simin , Liu, Wei et al. Research Progress of Chitosan-based Multifunctional Nanoparticles in Cancer Targeted Therapy [J]. | CURRENT MEDICINAL CHEMISTRY , 2024 , 31 (21) : 3074-3092 .
MLA Lai, Chunmei et al. "Research Progress of Chitosan-based Multifunctional Nanoparticles in Cancer Targeted Therapy" . | CURRENT MEDICINAL CHEMISTRY 31 . 21 (2024) : 3074-3092 .
APA Lai, Chunmei , Lin, Simin , Liu, Wei , Jin, Yanqiao . Research Progress of Chitosan-based Multifunctional Nanoparticles in Cancer Targeted Therapy . | CURRENT MEDICINAL CHEMISTRY , 2024 , 31 (21) , 3074-3092 .
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Preparation and performance exploration of 2,5-furandicarboxylic acid-based copolyester bioplastics: Controlling thermal properties, tensile properties, and surface hydrophilicity through composition SCIE
期刊论文 | 2024 , 141 (33) | JOURNAL OF APPLIED POLYMER SCIENCE
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Abstract :

To improve the comprehensive properties of polybutylene furandicarboxylate (PBF), 2,5-furandicarboxylic acid (2,5-FDCA), and aliphatic chain diol 1,8-octanediol and 1,4-butanediol were used as monomers to synthesize a series of bio-based polybutylene glycol-octanediol 2,5-furandicarboxylate (PBOF). The results showed that the chemical composition of PBOF could be controlled through the molar ratio of monomers. Compared with PBF, as the proportion of octanediol segments gradually increased, PBOF could gradually transform from semi-crystalline thermoplastic to amorphous form, and the glass transition temperature (Tg) gradually decreased. The crystallization ability reduced but a part of the crystal area was still retained. The copolyesters still has a decomposition temperature above 370 degrees C, indicating excellent thermal stability. The introduction of the octanediol segment significantly improved the tensile mechanical properties and flexibility of the POBF copolyester. These meet the requirements for the preparation of bio-based engineering plastics. The water absorption rate of PBOF showed that it may have certain degradable potential. PBOF copolyesters have potential application prospects in bio-based medical plastics and biodegradable packaging polymer materials after copolymerization modification. A series of high-value bio-based copoyesters were prepared from a kind of sustainable raw material, 2,5-furandicarboxylic acid. image

Keyword :

bio-based polymers bio-based polymers biomass utilization biomass utilization copolyesters copolyesters furan dicarboxylic acid furan dicarboxylic acid polycondensation polycondensation

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GB/T 7714 Xu, Jia , Zou, Haitao , Jin, Yanqiao et al. Preparation and performance exploration of 2,5-furandicarboxylic acid-based copolyester bioplastics: Controlling thermal properties, tensile properties, and surface hydrophilicity through composition [J]. | JOURNAL OF APPLIED POLYMER SCIENCE , 2024 , 141 (33) .
MLA Xu, Jia et al. "Preparation and performance exploration of 2,5-furandicarboxylic acid-based copolyester bioplastics: Controlling thermal properties, tensile properties, and surface hydrophilicity through composition" . | JOURNAL OF APPLIED POLYMER SCIENCE 141 . 33 (2024) .
APA Xu, Jia , Zou, Haitao , Jin, Yanqiao , Zheng, Qixi , Lei, Fanghui , Wu, Yuxin . Preparation and performance exploration of 2,5-furandicarboxylic acid-based copolyester bioplastics: Controlling thermal properties, tensile properties, and surface hydrophilicity through composition . | JOURNAL OF APPLIED POLYMER SCIENCE , 2024 , 141 (33) .
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虚实结合的高分子化学实验课程教学改革探索
期刊论文 | 2024 , 41 (04) , 142-149 | 化工高等教育
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Abstract :

为培养适应社会发展需要的应用型创新人才,文章针对高分子化学实验课程传统教学存在的问题,提出了一种虚拟仿真实验教学与传统实验教学相结合的实验教学模式。该教学模式的实施,有助于弥补传统实验教学的不足,激发学生的学习兴趣,锻炼学生的实践能力和创新思维,提高教学质量和效率,促进应用型创新人才的培养。

Keyword :

实验教学 实验教学 虚实结合 虚实结合 虚拟仿真 虚拟仿真 高分子化学实验 高分子化学实验

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GB/T 7714 张夏兰 , 吕秋丰 , 靳艳巧 et al. 虚实结合的高分子化学实验课程教学改革探索 [J]. | 化工高等教育 , 2024 , 41 (04) : 142-149 .
MLA 张夏兰 et al. "虚实结合的高分子化学实验课程教学改革探索" . | 化工高等教育 41 . 04 (2024) : 142-149 .
APA 张夏兰 , 吕秋丰 , 靳艳巧 , 林起浪 . 虚实结合的高分子化学实验课程教学改革探索 . | 化工高等教育 , 2024 , 41 (04) , 142-149 .
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Hydrolysis-dominated catalytic system: Hydrogen-free hydrogenolysis of lignin from Pd-MoO x /TiO 2 SCIE
期刊论文 | 2024 , 267 | INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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Abstract :

Lignin is continuously investigated by various techniques for valorization due to its high content of oxygencontaining functional groups. Catalytic systems employing hydrolysis-hydrogenolysis, leveraging the synergistic effect of redox metal sites and acid sites, exhibit efficient degradation of lignin. The predominance of either hydrolysis or hydrogenolysis reactions hinges upon the relative activity of acid and metal sites, as well as the intensity of the reductive atmosphere. In this study, the Pd-MoOx/TiO2 catalyst was found to primarily catalyze hydrolysis in the lignin depolymerization process, attributed to the abundance of moderate acidic sites on Pd and the redox-assisted catalysis of MoOx under inert conditions. After subjecting the reaction to 240 degrees C for 30 h, a yield of 48.22 wt% of total phenolic monomers, with 5.90 wt% consisting of diphenols, was achieved. Investigation into the conversion of 4-propylguaiacol (4-PG), a major depolymerized monomer of corncob lignin, revealed the production of ketone intermediates, a phenomenon closely linked to the unique properties of MoOx. Dehydrogenation of the propyl is a key step in initiating the reaction, and 4-PG could be almost completely transformed, accompanied by an over 97 % of 4-propylcatechol selectivity. This distinctive system lays a new theoretical groundwork for the eco-friendly valorization of lignin.

Keyword :

4-Propylguaiacol 4-Propylguaiacol Hydrogen-free Hydrogen-free Hydrogenolysis Hydrogenolysis Hydrolysis Hydrolysis Ketone Ketone Lignin Lignin

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GB/T 7714 Tang, Daobin , Lin, Xuebin , Zhang, Qi et al. Hydrolysis-dominated catalytic system: Hydrogen-free hydrogenolysis of lignin from Pd-MoO x /TiO 2 [J]. | INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES , 2024 , 267 .
MLA Tang, Daobin et al. "Hydrolysis-dominated catalytic system: Hydrogen-free hydrogenolysis of lignin from Pd-MoO x /TiO 2" . | INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 267 (2024) .
APA Tang, Daobin , Lin, Xuebin , Zhang, Qi , Wang, Zhenni , Liu, Yuhang , Jin, Yanqiao et al. Hydrolysis-dominated catalytic system: Hydrogen-free hydrogenolysis of lignin from Pd-MoO x /TiO 2 . | INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES , 2024 , 267 .
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Double core-shell hollow nanocage CuO@Co 3 O 4 for the selective hydrogenolysis of C-O bonds of lignin without external hydrogen SCIE
期刊论文 | 2024 , 491 | CHEMICAL ENGINEERING JOURNAL
WoS CC Cited Count: 1
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Abstract :

The design of a highly active Cu -Co catalyst for catalytic transfer hydrogenolysis of lignin without the use of external hydrogen remains highly challenging. In this work, Cu 2 O was initially encapsulated in ZIF-67, and subsequently Cu 2 O@ZIF-67 was utilized as a precursor and sacrificial template to prepare the unique double core-shell hollow nanocage CuO@Co 3 O 4 . Co and Cu, serving as Lewis acid sites and dehydrogenation sites for the hydrogen -donor solvent isopropanol, respectively, exhibited synergistic enhancement, further increasing the catalytic activity. Under the optimal conditions of 220 degrees C, 1 MPa N 2 , and 4 h, the catalyst achieved 100 % conversion of 2-phenoxy-1-phenylethanol and 100 % yield towards cyclohexanol and ethylbenzene. Furthermore, the catalyst remained stable and reusable after 5 cycles, providing a practicable guidance for the valueadded conversion of lignin.

Keyword :

C-O bonds cleavage C-O bonds cleavage CuCo-based catalyst CuCo-based catalyst Double core-shell hollow nanocage structure Double core-shell hollow nanocage structure Lignin Lignin

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GB/T 7714 Chen, Feng , Lin, Xuebin , Chen, Wei et al. Double core-shell hollow nanocage CuO@Co 3 O 4 for the selective hydrogenolysis of C-O bonds of lignin without external hydrogen [J]. | CHEMICAL ENGINEERING JOURNAL , 2024 , 491 .
MLA Chen, Feng et al. "Double core-shell hollow nanocage CuO@Co 3 O 4 for the selective hydrogenolysis of C-O bonds of lignin without external hydrogen" . | CHEMICAL ENGINEERING JOURNAL 491 (2024) .
APA Chen, Feng , Lin, Xuebin , Chen, Wei , Wen, Na , Jin, Yanqiao . Double core-shell hollow nanocage CuO@Co 3 O 4 for the selective hydrogenolysis of C-O bonds of lignin without external hydrogen . | CHEMICAL ENGINEERING JOURNAL , 2024 , 491 .
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High quantum yield nitrogen-doped carbon quantum dots: Green synthesis and application as "on-off" fluorescent sensors for specific Fe3+ions detection and cell imaging SCIE
期刊论文 | 2023 , 133 | DIAMOND AND RELATED MATERIALS
WoS CC Cited Count: 14
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Abstract :

A nitrogen-doped carbon quantum dots (N-CQDs)-based "on-off" fluorescent nanosensor was profitably synthe-sized through one-pot hydrothermal treatment of citric acid and o-phenylenediamine for the determination of Fe3+ and imaging towards cancerous cells in vitro. The synthesized N-CQDs exhibited excellent photo-luminescence and favorable biocompatibility. The excitation-dependent fluorescence emission spectra were observed and the maximum emission wavelength was 483 nm at the excitation wavelength of 420 nm. The fluorescent N-CQDs had a selective and sensitive response to Fe3+ with a limit of detection of 0.177 mu M and an allowable detection range of 0-110 mu M. The sensor was applied for the determination of Fe3+ ions in tap water with satisfactory results. Moreover, the N-CQDs provide a practical and promising method for cellular imaging due to their excellent fluorescence potency and negligible cytotoxicity.

Keyword :

Carbon quantum dots Carbon quantum dots Cell imaging Cell imaging Fe3+ions detection Fe3+ions detection Fluorescence probe Fluorescence probe

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GB/T 7714 Lai, Chunmei , Lin, Simin , Xiong, Lei et al. High quantum yield nitrogen-doped carbon quantum dots: Green synthesis and application as "on-off" fluorescent sensors for specific Fe3+ions detection and cell imaging [J]. | DIAMOND AND RELATED MATERIALS , 2023 , 133 .
MLA Lai, Chunmei et al. "High quantum yield nitrogen-doped carbon quantum dots: Green synthesis and application as "on-off" fluorescent sensors for specific Fe3+ions detection and cell imaging" . | DIAMOND AND RELATED MATERIALS 133 (2023) .
APA Lai, Chunmei , Lin, Simin , Xiong, Lei , Wu, Yuxin , Liu, Chao , Jin, Yanqiao . High quantum yield nitrogen-doped carbon quantum dots: Green synthesis and application as "on-off" fluorescent sensors for specific Fe3+ions detection and cell imaging . | DIAMOND AND RELATED MATERIALS , 2023 , 133 .
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Flexible liquid crystal micro-lens arrays for curved integral imaging 2D/3D convertible display SCIE
期刊论文 | 2023 , 50 (11-12) , 1666-1678 | LIQUID CRYSTALS
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Abstract :

Glasses-free three-dimensional (3D) displays are being regarded as the key to the future of display that will redefine the display industry. Inspired by the curved screen, liquid crystal micro-lens arrays (LC MLAs) on flexible PET substrate with a radius of curvature of 5 cm was achieved. For demonstration, an integral imaging-based 2D/3D convertible display system is proposed by using the flexible LC MLAs (FLC MLAs) to switch its operation mode between 2D and 3D modes. When the FLC MLAs with an applied voltage are in the system, the prototype renders a matched 3D image and works in 3D mode. When the FLC MLAs do not have an applied voltage, the FLC MLAs are equivalent to glass, and the display system works in 2D mode. In addition, we also demonstrated that the FLC MLAs have a wider viewing angle than the flat integral imaging 3D display system. The depth of field ranges from 6.78 to 210.12 mm under low operating voltages of 3.4 to 3.1 Vrms, respectively. With its low voltage, thin structure, and adjustable focal length form factors, the developed display system can be integrated with off-the-shelf purchased flat panels, making it a promising option for portable electronics.

Keyword :

2D 2D 3D convertible 3D convertible curved integral imaging curved integral imaging Flexible liquid crystal micro-lens array Flexible liquid crystal micro-lens array tunable focal length tunable focal length

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GB/T 7714 Wang, Wen-Wen , Peng, Yu-Yan , Weng, Xu-Yang et al. Flexible liquid crystal micro-lens arrays for curved integral imaging 2D/3D convertible display [J]. | LIQUID CRYSTALS , 2023 , 50 (11-12) : 1666-1678 .
MLA Wang, Wen-Wen et al. "Flexible liquid crystal micro-lens arrays for curved integral imaging 2D/3D convertible display" . | LIQUID CRYSTALS 50 . 11-12 (2023) : 1666-1678 .
APA Wang, Wen-Wen , Peng, Yu-Yan , Weng, Xu-Yang , Jin, Yan-Qiao , Zhou, Xiong-Tu , Yan, Qun et al. Flexible liquid crystal micro-lens arrays for curved integral imaging 2D/3D convertible display . | LIQUID CRYSTALS , 2023 , 50 (11-12) , 1666-1678 .
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CoS2 nanoparticles grown on Mo2TiC2Tx as an efficient electrocatalyst for hydrogen evolution reaction SCIE
期刊论文 | 2023 , 135 | DIAMOND AND RELATED MATERIALS
WoS CC Cited Count: 5
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At present, the development of cheap and efficient electrocatalytic hydrogen evolution catalyst is of great sig-nificance to the industrialization of hydrogen energy. In this work, Mo2TiC2Tx was firstly obtained by etching Mo2TiAlC2 with hydrofluoric acid (HF), and then CoS2 nanoparticles were grown on the surface of Mo2TiC2Tx to prepare CoS2@Mo2TiC2Tx catalyst by one-pot hydrothermal method. The hydrothermal vulcanization method for the preparation of CoS2@Mo2TiC2Tx electrocatalyst not only saves the experimental cost but also has higher vulcanization efficiency. Due to the synergistic effect of CoS2 and Mo2TiC2Tx, the CoS2@Mo2TiC2Tx catalyst exhibited good hydrogen evolution reaction catalytic activity in 0.5 M H2SO4; at a current density of 10 mA/cm2, the overpotential is only 132 mV, and the Tafel slope is 116 mV/dec. Besides, due to its unique morphology, CoS2@Mo2TiC2Tx still exhibits good durability after 24 h of continuous electrolysis. Therefore, this work pro-vides a possibility to realize non-precious metal electrocatalyst to replace Pt/C.

Keyword :

CoS2 CoS2 Electrocatalyst Electrocatalyst Hydrogen evolution reaction Hydrogen evolution reaction Mo2TiC2Tx Mo2TiC2Tx

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GB/T 7714 Chen, Xiao-Liang , Liu, Cong , Tang, Chou-Kun et al. CoS2 nanoparticles grown on Mo2TiC2Tx as an efficient electrocatalyst for hydrogen evolution reaction [J]. | DIAMOND AND RELATED MATERIALS , 2023 , 135 .
MLA Chen, Xiao-Liang et al. "CoS2 nanoparticles grown on Mo2TiC2Tx as an efficient electrocatalyst for hydrogen evolution reaction" . | DIAMOND AND RELATED MATERIALS 135 (2023) .
APA Chen, Xiao-Liang , Liu, Cong , Tang, Chou-Kun , Liu, Zhen-Hui , Lue, Qiu-Feng , Jin, Yanqiao . CoS2 nanoparticles grown on Mo2TiC2Tx as an efficient electrocatalyst for hydrogen evolution reaction . | DIAMOND AND RELATED MATERIALS , 2023 , 135 .
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Sustainable synthesis of lignin-derived carbon dots with visible pH response for Fe3+detection and bioimaging SCIE
期刊论文 | 2023 , 302 | SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
WoS CC Cited Count: 8
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Abstract :

Synthesis of lignin-based carbon dots (LCDs) with high quantum yield (QY), stable fluorescence properties and biocompatibility has been a challenge. Here, we propose an improved two-step strategy for producing highquality LCDs from enzymatic hydrolysis lignin (EHL). The p-aminobenzenesulfonic acid used in the strategy not only provides nitrogen and sulfur elements, but also tailors the disordered three-dimensional structure of EHL. The successful co-doping of N and S elements favors the reduction of the optical energy bandgap (Eg), resulting in a high QY of 45.05% for LCDs. The LCDs exhibited superior selectivity and sensitivity for Fe3+ with a limit of detection (LOD) of 0.15 & mu;M when Fe3+ concentration was 50-500 & mu;M. In addition, LCDs demonstrated significant fluorescence in HepG2 cells and HepG2 cells loaded with LCDs at a concentration of 80 & mu;g/mL showed good viability, suggesting that they are suitable for in vivo applications. The luminescent centers of LCDs change during pH regulation and thus show a special visual response to pH changes, making them have great potential for detecting metabolism in living cells. This work provides a novel and low-cost method for fabricating sustainable fluorescent probes for chemical sensing and bioimaging.

Keyword :

Bioimaging Bioimaging Carbon dots Carbon dots Enzymatic hydrolysis lignin Enzymatic hydrolysis lignin Fe 3+detection Fe 3+detection

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GB/T 7714 Lin, Simin , Lai, Chunmei , Huang, Zejie et al. Sustainable synthesis of lignin-derived carbon dots with visible pH response for Fe3+detection and bioimaging [J]. | SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY , 2023 , 302 .
MLA Lin, Simin et al. "Sustainable synthesis of lignin-derived carbon dots with visible pH response for Fe3+detection and bioimaging" . | SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 302 (2023) .
APA Lin, Simin , Lai, Chunmei , Huang, Zejie , Liu, Wei , Xiong, Lei , Wu, Yuxin et al. Sustainable synthesis of lignin-derived carbon dots with visible pH response for Fe3+detection and bioimaging . | SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY , 2023 , 302 .
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