emulsion stability

乳液稳定性
  • 文章类型: Journal Article
    花生分离蛋白(PPI)具有很高的营养价值,但其较差的功能限制了其在食品工业中的应用。在这项研究中,采用酶水解结合糖基化对花生分离蛋白进行改性。结构,研究了花生分离蛋白水解物(HPPI)和葡聚糖(Dex)缀合物(HPPI-Dex)的乳化和界面特性。此外,物理化学性质,流变性能,并对乳液的稳定性进行了研究。结果表明,接枝度随着Dex比的增加而增加。傅里叶变换红外光谱(FTIR)证实HPPI和Dex发生了糖基化。微观结构表明,HPPI-Dex的结构得到了扩展,分子的柔韧性增强了。当HPPI与Dex的比例为1:3时,糖化HPPI的乳化活性和界面压力达到最高值,HPPI-Dex的乳化活性(61.08m2/g)是PPI的5.28倍。HPPI-Dex稳定乳液具有良好的理化性能和流变性能。此外,HPPI-Dex稳定乳液在热处理条件下具有较高的稳定性,盐离子处理和冻融循环。根据共聚焦激光扫描显微镜(CLSM),HPPI-Dex稳定的乳液在储存28天后的分散性更好。本研究为开发花生蛋白乳化剂,进一步拓展花生蛋白在食品工业中的应用提供了理论依据。
    Peanut protein isolate (PPI) has high nutritional value, but its poor function limits its application in the food industry. In this study, peanut protein isolate was modified by enzymatic hydrolysis combined with glycation. The structure, emulsification and interface properties of peanut protein isolate hydrolysate (HPPI) and dextran (Dex) conjugate (HPPI-Dex) were studied. In addition, the physicochemical properties, rheological properties, and stability of the emulsion were also investigated. The results showed that the graft degree increased with the increase of Dex ratio. Fourier transform infrared spectroscopy (FTIR) confirmed that the glycation of HPPI and Dex occurred. The microstructure showed that the structure of HPPI-Dex was expanded, and the molecular flexibility was enhanced. When the ratio of HPPI to Dex was 1:3, the emulsifying activity and the interface pressure of glycated HPPI reached the highest value, and the emulsifying activity (61.08 m2/g) of HPPI-Dex was 5.28 times that of PPI. The HPPI-Dex stabilized emulsions had good physicochemical properties and rheological properties. In addition, HPPI-Dex stabilized emulsions had high stability under heat treatment, salt ion treatment and freeze-thaw cycle. According to confocal laser scanning microscopy (CLSM), the dispersion of HPPI-Dex stabilized emulsions was better after 28 days of storage. This study provides a theoretical basis for developing peanut protein emulsifier and further expanding the application of peanut protein in food industry.
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  • 文章类型: Journal Article
    使用绿色技术将天然淀粉转化为纳米颗粒是生产Pickering乳液稳定剂的一种有趣方法,针对清洁标签产品中高度稳定的乳液。采用纳米沉淀法制备Pickering淀粉纳米颗粒,而超声技术已被用来调节这些纳米颗粒的大小,同时开发的乳液。因此,本研究的主要目的是评估木薯淀粉纳米颗粒(SNP)的稳定作用,通过纳米沉淀技术结合超声处理在水和油(更疏水的物理化学环境)的存在下进行,不同于以前的研究,只在水的存在下进行机械处理。结果表明,增加的超声能量输入可以降低水分散体中的粒径(117.58至55.75nm)和多分散性(0.958至0.547)。随后,通过SNP稳定的Pickering乳液显示,增加乳化(超声处理)时间导致更小的液滴尺寸和单峰尺寸分布。尽管絮凝,长期超声处理(6和9分钟)在储存7天后几乎不会引起液滴大小的变化。空化效应有利于油滴之间通过弱吸引力和颗粒共享的相互作用,有利于Pickering稳定,防止液滴聚结。我们的结果表明,仅使用物理修饰来获得可以产生对环境友好的聚结稳定乳液的纳米颗粒的潜力。
    Using green techniques to convert native starches into nanoparticles is an interesting approach to producing stabilizers for Pickering emulsions, aiming at highly stable emulsions in clean label products. Nanoprecipitation was used to prepare the Pickering starch nanoparticles, while ultrasound technique has been used to modulate the size of these nanoparticles at the same time as the emulsion was developed. Thus, the main objective of this study was to evaluate the stabilizing effect of cassava starch nanoparticles (SNP) produced by the nanoprecipitation technique combined with ultrasound treatment carried out in the presence of water and oil (more hydrophobic physicochemical environment), different from previous studies that carry out the mechanical treatment only in the presence of water. The results showed that the increased ultrasound energy input could reduce particle size (117.58 to 55.75 nm) and polydispersity (0.958 to 0.547) in aqueous dispersions. Subsequently, Pickering emulsions stabilized by SNPs showed that increasing emulsification (ultrasonication) time led to smaller droplet sizes and monomodal size distribution. Despite flocculation, long-term ultrasonication (6 and 9 min) caused little variation in the droplet size after 7 days of storage. The cavitation effects favored the interaction between oil droplets through weak attraction forces and particle sharing, favoring the Pickering stabilization against droplet coalescence. Our results show the potential to use only physical modifications to obtain nanoparticles that can produce coalescence-stable emulsions that are environmentally friendly.
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  • 文章类型: Journal Article
    通过使有限的酶促水解改性的大米蛋白(HRP)原纤化,制备了抗氧化剂淀粉样蛋白原纤维作为乳化剂。目的探讨采用原纤化HRP稳定水包油乳状液的可行性。自由基清除实验表明,原纤化HRP的抗氧化活性是天然大米蛋白的2.09倍。纤维化HRP显示界面张力显著降低,增加表面疏水性和接触角(>80°),并快速吸附到界面上,具有35.34±2.43%的界面吸附蛋白含量。原纤化的HRP屏障抵抗了环境应力,例如NaCl,pH值变化,长期储存,同时降低脂质氧化程度。此外,与其他样品相比,原纤化HRP基乳液在保护β-胡萝卜素免于降解方面更有效。本研究结果为大米蛋白类抗氧化乳化剂的开发和植物蛋白乳化性能的改性提供了理论支持。
    An antioxidant amyloid fibril was prepared as an emulsifier by fibrillating limited enzymatic hydrolysis-modified rice protein (HRP). The purpose of this study was to investigate the feasibility of using fibrillated HRP to stabilize oil-in-water emulsion. A free radical scavenging assay revealed that the antioxidant activity of fibrillated HRP was 2.09 times higher than that of native rice protein. Fibrillated HRP demonstrated a marked reduction in interfacial tension, increased surface hydrophobicity and contact angle (> 80°), and rapid adsorption to the interface, with 35.34 ± 2.43% interfacial adsorbed protein content. The fibrillated HRP barriers resisted environment stresses such as NaCl, pH variations, long-term storage, while reducing lipid oxidation degree. Additionally, fibrillated HRP-based emulsion was more effective in protecting β-carotene from degradation compared to other samples. These findings provide theoretical support for the development of rice protein-based antioxidant emulsifiers and modification of emulsifying properties of plant proteins.
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  • 文章类型: Journal Article
    由于果肉强化的无脂搅拌酸奶的稳定性和流变学特性较差,新型功能性多糖作为天然乳化剂,可以增加水相中的粘度,可能需要。本研究的目的是评价附子多糖(EYP)作为乳化剂对其稳定性的影响,香气,和芒果水牛酸奶在4°C下25天的抗氧化活性。含15g/LEYP的酸奶总固体含量较高,为215g/L,11.3g/L胞外多糖,0.10g/L总多酚,630.5g/L持水能力,和11.43g/kg总游离氨基酸,并保持更好的质地,DPPH清除活性为54.05%,OH清除率为67.16%。此外,EYP表现出预期的减弱后酸化的能力,脱水收缩,和微生物的生长,极大地促进了纹理,流变性能,悬浮稳定性,微观结构,搅拌芒果味水牛酸奶的香气特征(p<0.05)。此外,15g/LEYP的添加可以抑制芒果酸奶中蛋白质的降解,提高其二级结构的稳定性。因此,EYP(15g/L)可作为天然的正功能因子和乳化剂用于无脂搅拌酸奶行业。
    Because of the poor stability and rheological properties of fat-free stirred yogurt fortified with fruit pulp, new functional polysaccharides as a natural emulsifier, which can increase viscosity in the aqueous phase, may be needed. This study aimed to evaluate the effects of Exidia yadongensis polysaccharide (EYP) as emulsifier on the stability, aroma, and antioxidant activities of mango buffalo yogurt at 4 °C for 25 days. The yogurt with 15 g/L EYP gave a higher content of 215 g/L total solids, 11.3 g/L exopolysaccharides, 0.10 g/L total polyphenols, 630.5 g/L water-holding capacity, and 11.43 g/kg total free amino acids, and maintained better texture, DPPH scavenging activity of 54.05 % and OH scavenging rates of 67.16 %. Moreover, the EYP exhibited the expected ability to weaken postacidification, syneresis, and growth of microorganism, and greatly promote the textural, rheological properties, suspension stability, microstructure, and aroma profiles of stirred mango-flavored buffalo yogurt (p < 0.05). In addition, the addition of 15 g/L EYP can inhibit protein degradation and improve the stability of secondary structure of the protein complex in mango yogurt during 25 days of storage. Therefore, EYP (15 g/L) could be used as natural positive functional factors and emulsifiers in such fat-free stirred yogurt industry.
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  • 文章类型: Journal Article
    这项研究调查了在制备低脂蛋黄酱(LFM)中使用a菜蛋白分离物(API)作为基于植物的蛋黄(EY)替代品的可能性。采用碱提取/酸性沉淀法分离提取了苜蓿蛋白,并对其功能性质进行了研究。结果表明,除了具有良好的吸水能力和吸油能力外,与碱性pH值相比,API在pH2.0下具有更好的乳化能力和显着更高的(p<.05)乳液稳定性。具有不同API/EY组合比率(%)的五个蛋黄酱样品(即,制备0/0.75、0.25/0.5、0.375/0.375、0.5/0.25和0.75/0)。颜色,乳液稳定性(ES),冻融稳定性(FTS),液滴大小,结构,流变学,并对样品的感官性能进行了检查。原料药替换对L*值无不良影响,ES,和感官属性(p>0.05)。低API浓度(0.25%和0.375%)显著(p<.05)增加了液滴尺寸并降低了LFM乳液的FTS。高API浓度(0.5%和0.75%)对液滴尺寸没有显著影响(p>.05),并且形成具有更紧密包装的油滴的乳液。选择Cross模型最好地描述LFM样品的流动行为(R2=0.99)。含0.75%API的样品具有显著(p<.05)的最高值ηo(零剪切粘度)和λ(弛豫时间),表明乳液颗粒之间的相互作用更大。所有样品显示弱凝胶结构(G\'>G\")。总之,API可以被认为是LFM生产中EY的合适替代品,这可以有益于人类健康,并为准备素食产品提供了新的策略。
    This study investigated the possibility of using amaranth protein isolate (API) as a plant-based substitute for egg yolk (EY) in the preparation of low-fat mayonnaise (LFM). The alkali extraction/acidic precipitation method was used to isolate amaranth protein; its functional properties were then studied. The results showed that besides its great water and oil absorption capacities, API had better emulsifying capacity and significantly higher (p < .05) emulsion stability at pH 2.0 than alkali pH values. Five mayonnaise samples with different API/EY combination ratios (%) (i.e., 0/0.75, 0.25/0.5, 0.375/0.375, 0.5/0.25, and 0.75/0) were prepared. The color, emulsion stability (ES), freeze-thaw stability (FTS), droplet size, structure, rheology, and sensory properties of samples were examined. API replacement showed no adverse effects on the L* value, ES, and sensory attributes (p > .05). Low API concentrations (0.25% and 0.375%) significantly (p < .05) increased the droplet size and decreased the FTS of LFM emulsion. High API concentrations (0.5% and 0.75%) had no significant effect (p > .05) on droplet size and formed emulsions with more tightly packed oil droplets. The Cross model was chosen best to describe the flow behavior of LFM samples (R 2 = 0.99). The sample with 0.75% API had significantly (p < .05) the highest values of η o (zero-shear viscosity) and λ (relaxation time), indicating greater interaction between the emulsion particles. All samples showed a weak gel structure (G\' > G\"). In conclusion, API can be considered an appropriate substitute for EY in LFM production, which can benefit human health and offer a new strategy for preparing vegan products.
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  • 文章类型: Journal Article
    1,2-二炔酰-sn-甘油-3-磷酸胆碱(DMPC)是一种有前途的生物活性传递系统的乳化剂,但由于缺乏具有成本效益和可扩展的合成路线,其工业应用受到限制。本研究的目的是通过替代常用的柱色谱法经济地生产高纯度DMPC,并评估乳化性能。
    DMPC由sn-甘油-3-磷酸胆碱使用Steglich酯化然后从乙酸乙酯和丙酮中连续重结晶来合成。使用各种光谱和色谱技术鉴定DMPC的结构并确认其纯度。通过检查储存对使用大豆油与(i)大豆PC制备的o/w乳液的性能的影响来评估乳化性能,(ii)大豆PC+DMPC(1:1,w/w),和(iii)作为乳化剂的DMPC。
    去除了DMPC合成过程中形成的化学杂质,最终纯度为96%,熔融转变温度为37.6℃。三种乳液(大豆PC,大豆PC+DMPC,和DMPC)在两周的储存期间观察到,DMPC型乳液比大豆PC型乳液更稳定,在6个月内显示较小的粒度分布。
    通过经济的方法合成了高纯度的DMPC,基于DMPC的乳液表现出物理化学稳定,强调其在食品和制药行业相关应用中的潜力。我们的发现表明,DMPC有望作为乳化剂在食品工业中具有广泛的应用。
    UNASSIGNED: 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) is a promising emulsifier for bioactive delivery systems, but its industrial applications are limited by the lack of cost-effective and scalable synthetic routes. The purpose of this study was to economically produce high-purity DMPC by replacing commonly used column chromatography methods and to evaluate the emulsifying performance.
    UNASSIGNED: DMPC was synthesized from sn-glycero-3-phosphocholine using Steglich esterification followed by sequential recrystallization from ethyl acetate and acetone. The structure of DMPC was identified and its purity was confirmed using various spectroscopy and chromatography techniques. The emulsifying performance was evaluated by examining the effects of storage on the properties of o/w emulsions prepared using soybean oil with (i) soy PC, (ii) soy PC + DMPC (1:1, w/w), and (iii) DMPC as emulsifiers.
    UNASSIGNED: The chemical impurities formed during the synthesis of DMPC was removed, and its final purity was 96%, and the melt transition temperature was 37.6°C. No visible difference between the three emulsions (soy PC, soy PC+DMPC, and DMPC) was observed during two-week storage, and the DMPC-based emulsion was more stable than soy PC emulsion, showing smaller particle size distribution during 6 months.
    UNASSIGNED: The highly pure DMPC was synthesized by an economical method, and DMPC-based emulsions demonstrated physicochemical stable, highlighting its potential for food and pharmaceutical industry-related applications. Our findings suggest that DMPC holds promise as an emulsifier with broad applications in the food industry.
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  • 文章类型: Journal Article
    蛋白质的功能特性受其聚集行为和形态的影响。在这项研究中,具有特定形态的自组装椰子蛋白聚集体,包括小的无定形聚集体(WLA),球形聚集体(SLA)和杆状聚集体(RLA),被规范形成。自组装过程导致椰子蛋白的荧光强度降低和表面疏水性增加。添加岩藻聚糖以提高蛋白质溶液的稳定性,并通过膨胀流变分析评估了界面吸附行为。结果表明,椰子蛋白的聚集状态影响其降低表面张力的能力,界面层主要在油水界面表现出弹性(tanφ<0.5)。对于宏观分析,基于自组装椰子蛋白的乳液表现出更小的液滴尺寸,更好的流变性能和离心稳定性,尤其是WLA和RLA.本研究可为自组装椰子蛋白在食品工业中的应用提供参考。
    The functional properties of protein are affected by their aggregation behavior and morphology. In this study, the self-assembled coconut protein aggregates with specific morphology, including small amorphous aggregates (WLA), spherical-like aggregates (SLA) and rod-like aggregates (RLA), were regulated to form. The self-assembled process resulted in a decrease in fluorescence intensity and an increase in the surface hydrophobicity of coconut protein. Fucoidan was added to improve the stability of protein solutions, and the interfacial adsorption behavior was evaluated by dilatational rheology analysis. The results showed that the aggregation state of coconut protein affected its ability to reduce surface tension, and the interfacial layers mainly exhibited elastic property at oil-water interface (tanφ < 0.5). For macroscale analysis, the emulsions based on self-assembled coconut protein exhibited smaller droplet size, better rheological properties and centrifugal stability, especially WLA and RLA. This study may provide a reference to inspire the utilization of self-assembled coconut protein in the food industry.
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  • 文章类型: Journal Article
    乳状液膜(ELM)作为一种提取工艺,因其在工业废水处理技术中的广阔前景而备受关注。然而,关键的挑战是达到高的膜稳定性以克服在工业规模上应用ELM的障碍。在这项研究中,通过在汽提相(W1)中使用纳米颗粒(超顺磁性氧化铁(Fe2O3))和在油相(O)中使用离子液体(1-甲基-3-辛基-咪唑-六氟磷酸盐[OMIM][PF6)来提高ELM,以从合成废水中回收/提取钒至接近完成,同时增强乳液稳定性以适合工业应用。当在内部相(W1)中添加0.01%(w/w)Fe2O3NP(尺寸为20至50nm)和在油相中(O)中添加5%(v/v)[OMIM]PF6离子液体时,钒回收/提取百分比在3分钟内显著提高至99.6%。此外,乳液稳定性有了很大提高,3天后,泄漏率降低至16%。这项研究的结果可用于将来从工业废水中去除更多的重金属离子。
    Emulsion liquid membrane (ELM) stands out as an extraction process that has drawn much attention due to its promising prospects in industrial wastewater treatment technology. Nevertheless, the pivotal challenge is to reach high membrane stability to overcome the obstacle of applying ELM at the industrial scale. In this study, ELM was boosted by using nanoparticles (superparamagnetic iron oxide (Fe2O3)) in the stripping phase (W1) and ionic liquid (1-methyl-3-octyl-imidazolium-hexafluorophosphate [OMIM][PF6) in the oil phase (O) for recovering/extracting vanadium from synthetic wastewater to near completion and at the same time enhancing emulsion stability to be appropriate for industrial application. The vanadium recovery/extraction percentage has been raised significantly in 3 min to 99.6% when adding 0.01% (w/w) Fe2O3 NPs (20 to 50 nm in size) in the internal phase (W1) and 5% (v/v) [OMIM]PF6 ionic liquid in the oil phase (O). Also, the emulsion stability was considerably improved, and the leakage percentage was reduced to 16% after 3 days. The results of this study could be used in the future to remove additional heavy metal ions from industrial effluents.
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  • 文章类型: Journal Article
    从加工副产品中提取椰子油(CPO)可增加产品价值并减少资源浪费。这项研究旨在评估20kHz的影响,20/80kHz和20/40/80kHz的多频超声辅助酶法提取(MFUAEE)对产率的影响,物理化学性质,脂肪酸组成,总酚含量,抗氧化活性,和来自湿椰子油(WCP)的CPO的乳液稳定性。结果表明,MFUAEE的CPO提取率比AEE高32.58%-43.31%。三频20/40/80kHz模式的多频超声预处理具有最高的CPO提取率(70.08%)。通过MFUAEE提取的油显示出与AEE相似的脂肪酸谱,但过氧化物值较低,K232和K270值。特别是,MFUAEE油含有较高的总酚含量,并表现出有效的DPPH自由基清除能力。通过SEM观察的结果表明,多频超声预处理更有效地破坏了WCP的细胞结构。此外,MFUAEE通过超声的空化作用增强乳液稳定性。这些发现表明,MFUAEE是获得CPO的一种有价值的方法,具有较高的提取率和优越的质量,从而提高椰子副产品的利用率。
    Extraction of coconut paring oil (CPO) from processing by-products adds value to the product and reduces resource wastage. This study aims to assess the impact of 20 kHz, 20/80 kHz and 20/40/80 kHz of multi-frequency ultrasonic-assisted enzymatic extraction (MFUAEE) on the yield, physicochemical properties, fatty acid composition, total phenolic content, antioxidant activity, and emulsion stability of CPO derived from wet coconut parings (WCP). Results revealed that the CPO extraction yield with MFUAEE was 32.58 % - 43.31 % higher compared to AEE. The tri-frequency 20/40/80 kHz mode of multi-frequency ultrasound pretreatment exhibited the highest CPO extraction yield (70.08 %). The oil extracted through MFUAEE displayed similar fatty acid profiles to AEE, but had lower peroxide value, K232 and K270 values. Particularly, MFUAEE oil contained higher total phenolic content and exhibited potent DPPH free radical scavenging capacity. Results observed by SEM indicated that the pretreatment with multi-frequency ultrasound more efficiently disrupts the cellular structure of the WCP. Additionally, MFUAEE enhanced emulsion stability through the cavitation effect of ultrasound. These findings suggest that MFUAEE is a valuable approach for method for obtaining CPO with elevated extraction yield and superior quality, thereby enhancing the utilization of coconut by-products.
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  • 文章类型: Journal Article
    制备了不同pH值(2.5-6.0)和生物聚合物质量比(1:1-6:1)的乳清分离蛋白(WPI)和两种多糖(杏仁胶(AG)和高甲氧基果胶(HMP))的复合凝聚层,以实现最大的凝聚层产量(CY)。获得WPI-AG(75.93%)和WPI-HMP(53.0%)凝聚物的最大CY的最佳pH和混合比分别为4.3和2:1,3.5和3:1。尽管在90°C下检测到由WPI-AG/HMP凝聚物稳定的乳液中的较高血清层,在具有两种复杂凝聚体的非原位乳液中,在加工温度下获得了显着的热稳定性。与WPI-HMP相比,用WPI-AG配制的乳液观察到显著更多的冷藏和离子稳定性。与单独的WPI和AG生物聚合物相比,WPI-AG凝聚体中的FTIR光谱中的峰位移揭示了这些生物聚合物之间的强静电相互作用。在X射线衍射(XRD)光谱中不存在AG和HMP的结晶峰证实了AG和HMP与WPI的络合。热重和微观结构分析表明,多孔,与WPI-HMP凝聚体和单个生物聚合物相比,松散网状WPI-AG凝聚体具有优异的热稳定性和结构完整性,这证明了一种更渐进的减肥模式。WPI-AG凝聚物有希望用于有效的基于乳液的递送系统。
    Complex coacervates of whey protein isolate (WPI) and two polysaccharides (almond gum (AG) and high methoxyl pectin (HMP)) under the different pHs (2.5-6.0) and biopolymer mass ratios (1:1-6:1) were prepared to achieve the maximum coacervate yield (CY). The optimum pH and mixing ratio to obtain the maximum CY of WPI-AG (75.93 %) and WPI-HMP (53.0 %) coacervates were 4.3 and 2:1, and 3.5 and 3:1, respectively. Although higher serum layers in emulsions stabilized by WPI-AG/HMP coacervates were detected at the 90 °C, remarkable heat stability under processing temperatures was obtained in ex-situ emulsions with both complex coacervates. Significantly more cold-storage and ionic stabilities were observed for emulsions formulated with WPI-AG than WPI-HMP. Peak shifts in FTIR spectra in the WPI-AG coacervate compared to the individual WPI and AG biopolymers revealed strong electrostatic interactions between these biopolymers. The absence of crystalline peaks for AG and HMP in X-ray diffraction (XRD) spectra confirmed the complexation of AG and HMP with WPI. Thermogravimetric and microstructural analyses showed that porous, loose mesh-like WPI-AG coacervates had superior thermal stability and structural integrity compared to WPI-HMP coacervates and individual biopolymers, which evidenced a more gradual weight loss pattern. WPI-AG coacervates would be promising for efficient emulsion-based delivery systems.
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