Surface decoration

  • 文章类型: Journal Article
    研究了通过氧化魔芋葡甘聚糖(OKGM)表面修饰来增强原花青素脂质体(PC-Lip)的稳定性。OKGM包被的PC-Lip(OKGM-PC-Lip)的包封率和载药量显著上升。OKGM-PC-Lip的平均大小和PDI增加,而zeta电位与PC-Lip相比降低。用OKGM涂覆后,PC-唇膜流动性降低。OKGM-PC-Lip的形态表明在脂质体表面形成了OKGM“晕层”。氢键在OKGM和PC-Lip的结合中起着不可或缺的作用,用OKGM涂覆后,PC-Lip的相变温度略有升高。OKGM-PC-Lip在极端pH下的保留率高于PC-Lip。体外释放,在胃期,OKGM-PC-Lip和PC-Lip之间的累积释放没有显着差异,肠道期OKGM-PC-Lip的累积释放速率明显低于PC-Lip。OKGM-PC-Lip的抗氧化活性明显高于PC-Lip。这些结果表明,用OKGM涂覆后,PC-Lip对外部影响的抵抗力得到了有效增强。与其他多糖相比,由于多糖对人体健康的益处,OKGM包被的脂质体在功能性食品中可能更有前途和优势。
    The stability enhancement of proanthocyanidin-loaded liposomes (PC-Lip) via surface decoration with oxidized konjac glucomannan (OKGM) was investigated. The encapsulation efficiency and drug loading capacity of OKGM-coated PC-Lip (OKGM-PC-Lip) rose significantly. The average size and PDI of OKGM-PC-Lip increased, while the zeta potential decreased compared to those of PC-Lip. PC-Lip membrane fluidity reduced after coating with OKGM. The morphology of OKGM-PC-Lip showed that OKGM \"halo layer\" was formed on the liposome surface. Hydrogen bonding played an indispensable role in the combination between OKGM and PC-Lip, and the phase transition temperature of PC-Lip slightly increased after coating with OKGM. The retention rate of OKGM-PC-Lip was higher than that of PC-Lip at extreme pH. In vitro release, no significant difference in cumulative release was detected between OKGM-PC-Lip and PC-Lip at gastric stage, while the cumulative release rate of OKGM-PC-Lip was remarkably lower than that of PC-Lip at intestinal stage. The antioxidant activity of OKGM-PC-Lip was notably higher than that of PC-Lip. These results suggested that the resistance of PC-Lip to external influences was fruitfully enhanced after coating with OKGM. Compared with other polysaccharides, OKGM-coated liposomes may be more promising and advantageous in functional foods due to the polysaccharide\'s benefits to human health.
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  • 文章类型: Journal Article
    贵金属纳米晶体在有效催化以电化学乙醇氧化反应(EOR)为代表的多步反应方面面临挑战,由于中间体结合能之间的线性比例关系,多电子转移过程,阻碍各个元素步骤的独立优化。在这里,我们开发的贵金属纳米晶体具有一系列的局部表面结合亲和力,以克服这一挑战。实验上,这通过对Pd表面施加拉伸应变并用离散的Au原子装饰来证明,在客体分子附近形成具有不同亲和力的多种结合位点,CO探测和密度泛函理论计算证明了这一点。这种表面使反应中间体能够根据每个元素步骤的需要在不同的结合位点之间迁移。从而当与单个位点处的反应相比时,降低了总EOR的能量势垒。在这些量身定制的表面上,我们在EOR中获得了32.7mAcm-2和47.8AmgPd-1的比和质量活性,分别超过商用Pd/C10.9倍和43.8倍,分别,和优于现有技术的Pd基催化剂。这些结果突出了这种方法在改进各种多步骤,多电子转移反应,这对能量转换应用至关重要。
    Noble metal nanocrystals face challenges in effectively catalyzing electrochemical ethanol oxidation reaction (EOR)-represented multistep, multielectron transfer processes due to the linear scaling relationship among binding energies of intermediates, impeding independent optimization of individual elemental steps. Herein, we develop noble metal nanocrystals with a range of local surface binding affinities in close proximity to overcome this challenge. Experimentally, this is demonstrated by applying tensile strain to a Pd surface and decorating it with discrete Au atoms, forming a diversity of binding sites with varying affinities in close proximity for guest molecules, as evidenced by CO probing and density functional theory calculations. Such a surface enables reaction intermediates to migrate between different binding sites as needed for each elemental step, thereby reducing the energy barrier for the overall EOR when compared to reactions at a single site. On these tailored surfaces, we attain specific and mass activities of 32.7 mA cm-2 and 47.8 A mgPd-1 in EOR, surpassing commercial Pd/C by 10.9 and 43.8 times, respectively, and outperforming state-of-the-art Pd-based catalysts. These results highlight the promise of this approach in improving a variety of multistep, multielectron transfer reactions, which are crucial for energy conversion applications.
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  • 文章类型: Journal Article
    具有多功能功能的光电传感器已经成为未来光电系统在各种应用中取得突破的基石。特别是,新兴的光电化学(PEC)型装置最近吸引了广泛的兴趣,在基于液体的生物传感应用,由于其天然的电解质辅助操作特性。在这里,通过在硅上使用氮化镓(GaN)p-n同质结半导体纳米线,精心设计和构造了PEC型光传感器,p-GaN段战略掺杂,然后用钴镍氧化物(CoNiOx)装饰。本质上,p-n同质结结构与容易的p-掺杂工程提高载流子分离效率,促进载流子转移到纳米线表面,而CoNiOx装饰进一步增强PEC反应活性和载体动力学在纳米线/电解质界面。因此,构造的光电传感器实现了247.8mAW-1的高响应度,同时具有出色的操作稳定性。引人注目的是,基于设备的显着稳定性和高响应性,建立了一个葡萄糖传感系统,演示了真实人血清中的葡萄糖水平测定。这项工作提供了一种可行和通用的方法,通过合理设计具有战略性掺杂工程的纳米结构体系结构形式的PEC器件,来追求高性能的生物相关传感应用。
    Photosensors with versatile functionalities have emerged as a cornerstone for breakthroughs in the future optoelectronic systems across a wide range of applications. In particular, emerging photoelectrochemical (PEC)-type devices have recently attracted extensive interest in liquid-based biosensing applications due to their natural electrolyte-assisted operating characteristics. Herein, a PEC-type photosensor was carefully designed and constructed by employing gallium nitride (GaN) p-n homojunction semiconductor nanowires on silicon, with the p-GaN segment strategically doped and then decorated with cobalt-nickel oxide (CoNiOx). Essentially, the p-n homojunction configuration with facile p-doping engineering improves carrier separation efficiency and facilitates carrier transfer to the nanowire surface, while CoNiOx decoration further boosts PEC reaction activity and carrier dynamics at the nanowire/electrolyte interface. Consequently, the constructed photosensor achieves a high responsivity of 247.8 mA W-1 while simultaneously exhibiting excellent operating stability. Strikingly, based on the remarkable stability and high responsivity of the device, a glucose sensing system was established with a demonstration of glucose level determination in real human serum. This work offers a feasible and universal approach in the pursuit of high-performance bio-related sensing applications via a rational design of PEC devices in the form of nanostructured architecture with strategic doping engineering.
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  • 文章类型: Journal Article
    纳米晶体(NC)技术已成为配制难溶性活性物质的最常用策略之一。鉴于它们的大比表面,NCs主要用于增强难溶性活性物质的口服吸收。不同于传统的纳米粒子,这需要使用载体材料和有限的药物负载,NCs的载药量接近100%,因为它们是由纯药物形成的,并且被稳定剂的薄层包围。在这项工作中,我们报告了使用EDC/NHS化学对姜黄素NC与叶酸(FA)的共价修饰,并探索了新型系统作为高负荷的“特洛伊木马”靶向癌细胞。装饰的NC表现出姜黄素吸收的显着改善,在癌细胞(HeLa和MCF7)中表现出增强的生长抑制,同时保留健康细胞(J774A.1)。细胞摄取研究显示,与未修饰的NC相比,FA修饰的NC进入癌细胞显着增加,同时也显示巨噬细胞的摄取减少。表明体内循环延长的可能性。这些发现强调了NC高负荷纳米载体用于药物递送的潜力,特别是,癌症治疗,有效靶向叶酸受体过表达细胞,同时避免巨噬细胞的拦截,从而保持它们的生存能力,并为精确和有效的治疗提供有希望的途径。
    The nanocrystal (NC) technology has become one of the most commonly used strategies for the formulation of poorly soluble actives. Given their large specific surface, NCs are mainly used to enhance the oral absorption of poorly soluble actives. Differently from conventional nanoparticles, which require the use of carrier materials and have limited drug loadings, NCs\' drug loading approaches 100% since they are formed of the pure drug and surrounded by a thin layer of a stabilizer. In this work, we report the covalent decoration of curcumin NCs with folic acid (FA) using EDC/NHS chemistry and explore the novel systems as highly loaded \"Trojan horses\" to target cancer cells. The decorated NCs demonstrated a remarkable improvement in curcumin uptake, exhibiting enhanced growth inhibition in cancer cells (HeLa and MCF7) while sparing healthy cells (J774A.1). Cellular uptake studies revealed significantly heightened entry of FA-decorated NCs into cancer cells compared to unmodified NCs while also showing reduced uptake by macrophages, indicating a potential for prolonged circulation in vivo. These findings underline the potential of NC highly loaded nanovectors for drug delivery and, in particular, for cancer therapies, effectively targeting folate receptor-overexpressing cells while evading interception by macrophages, thus preserving their viability and offering a promising avenue for precise and effective treatments.
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  • 文章类型: Journal Article
    铋(Bi)具有很高的理论容量,优异的导电性能,和显着的层间间距,使其成为超级电容器的理想电极材料。然而,在充电和放电过程中,Bi容易体积膨胀和粉化,导致电容下降。在其表面沉积非金属被认为是调节其形态和电子结构的有效方法。在这里,我们采用化学气相沉积技术在镍泡沫(NF)衬底上制造Se装饰的Bi纳米片。各种表征表明,Se在Bi纳米片上的沉积调节了其表面形态和化学状态,同时维持其原始相结构。电化学测试表明,与原始Bi纳米片相比,Se修饰的Bi纳米片表现出51.1%的容量改善(在5A/g的电流密度下,1313F/g与869F/g相比)。在800W/kg的功率密度下,组装的非对称超级电容器中的活性材料的能量密度可以达到151.2Wh/kg。这些发现表明Se修饰是增强Bi纳米片容量的有前途的策略。
    Bismuth (Bi) exhibits a high theoretical capacity, excellent electrical conductivity properties, and remarkable interlayer spacing, making it an ideal electrode material for supercapacitors. However, during the charge and discharge processes, Bi is prone to volume expansion and pulverization, resulting in a decline in the capacitance. Deposition of a nonmetal on its surface is considered an effective way to modulate its morphology and electronic structure. Herein, we employed the chemical vapor deposition technique to fabricate Se-decorated Bi nanosheets on a nickel foam (NF) substrate. Various characterizations indicated that the deposition of Se on Bi nanosheets regulated their surface morphology and chemical state, while sustaining their pristine phase structure. Electrochemical tests demonstrated that Se-decorated Bi nanosheets exhibited a 51.1% improvement in capacity compared with pristine Bi nanosheets (1313 F/g compared to 869 F/g at a current density of 5 A/g). The energy density of the active material in an assembled asymmetric supercapacitor could reach 151.2 Wh/kg at a power density of 800 W/kg. These findings suggest that Se decoration is a promising strategy to enhance the capacity of the Bi nanosheets.
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  • 文章类型: Journal Article
    这项科学研究强调了自然影响在制作多功能表面与生物灵感设计中的基本整合,以增强功能和环境优势。这项研究引入了一种创新的方法,合并颜色装饰,湿度传感,和抗病毒性能到一个统一的表面使用壳聚糖,一种有机生物聚合物,通过溶胶-凝胶沉积和UV光诱导沉积金属纳米颗粒来创建具有成本效益的多层膜。所得的壳聚糖膜展示了不同的结构颜色,并表现出显著的抗病毒效率,在快速的20分钟反应内具有50%和85%的病毒抑制率,通过荧光细胞表达和实时qPCR(聚合酶链反应)测定进行验证。银沉积壳聚糖膜进一步增强抗病毒活性,在独立测定中实现显著的91%和95%抑制。这些薄膜在25-90%的相对湿度范围内表现出对湿度敏感的颜色变化,通过仿真研究验证了实时监控。所提出的三合一功能表面可以在表面装饰中具有广泛的应用,医学,空调,和食品工业。它可以作为室内和室外表面的实时湿度传感器,找到用于生物医学设备的连续湿度监测,并为经常处理的设备和工具提供抗病毒保护。可定制的颜色增强了视觉吸引力,使其成为多样化应用的综合解决方案。
    This scientific investigation emphasizes the essential integration of nature\'s influence in crafting multifunctional surfaces with bio-inspired designs for enhanced functionality and environmental advantages. The study introduces an innovative approach, merging color decoration, humidity sensing, and antiviral properties into a unified surface using chitosan, an organo-biological polymer, to create cost-effective multilayered films through sol-gel deposition and UV photoinduced deposition of metal nanoparticles. The resulting chitosan films showcase diverse structural colors and demonstrate significant antiviral efficiency, with a 50% and 85% virus inhibition rate within a rapid 20 min reaction, validated through fluorescence cell expression and real-time qPCR (polymerase chain reaction) assays. Silver-deposited chitosan films further enhance antiviral activity, achieving remarkable 91% and 95% inhibition in independent assays. These films exhibit humidity-responsive color modifications across a 25-90% relative humidity range, enabling real-time monitoring validated through simulation studies. The proposed three-in-one functional surface can have versatile applications in surface decoration, medicine, air conditioning, and the food industry. It can serve as a real-time humidity sensor for indoor and outdoor surfaces, find use in biomedical devices for continuous humidity monitoring, and offer antiviral protection for frequently handled devices and tools. The customizable colors enhance visual appeal, making it a comprehensive solution for diverse applications.
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  • 文章类型: Journal Article
    析氧反应(OER)由于其在可再生能源系统中的关键作用而受到广泛关注。寻求有效和低成本的OER催化剂仍然是一个具有重要意义和重要性的挑战。在这项工作中,据报道,掺入磷酸盐的硅酸钴氢氧化物(表示为CoSi-P)是OER的潜在电催化剂。研究人员首先使用SiO2球体作为模板,通过简单的水热法合成了硅酸钴氢氧化物Co3(Si2O5)2(OH)2(表示为CoSi)的空心球。然后将磷酸盐(PO43-)引入层状CoSi,导致空心球重建为片状建筑。不出所料,所得CoSi-P电催化剂表现出低的过电位(10mA·cm-2时309mV),大电化学活性表面积(ECSA),和低的塔菲尔坡度。这些参数优于CoSi空心球和磷酸钴(表示为CoPO)。此外,在10mA/cm-2下实现的催化性能与大多数过渡金属硅酸盐/氧化物/氢氧化物相当或甚至更好。研究结果表明,在CoSi的结构中掺入磷酸盐可以增强其OER性能。这项研究不仅提供了一种非贵金属催化剂CoSi-P,而且还表明,将磷酸盐掺入过渡金属硅酸盐(TMS)中提供了一种有前途的策略,高效率,和低成本的OER催化剂。
    Oxygen Evolution Reaction (OER) has gained significant attention due to its crucial role in renewable energy systems. The quest for efficient and low-cost OER catalysts remains a challenge of significant interest and importance. In this work, phosphate-incorporated cobalt silicate hydroxide (denoted as CoSi-P) is reported as a potential electrocatalyst for OER. The researchers first synthesized hollow spheres of cobalt silicate hydroxide Co3(Si2O5)2(OH)2 (denoted as CoSi) using SiO2 spheres as a template through a facile hydrothermal method. Phosphate (PO43-) was then introduced to layered CoSi, leading to the reconstruction of the hollow spheres into sheet-like architectures. As expected, the resulting CoSi-P electrocatalyst demonstrated low overpotential (309 mV at 10 mA·cm-2), large electrochemical active surface area (ECSA), and low Tafel slope. These parameters outperform CoSi hollow spheres and cobaltous phosphate (denoted as CoPO). Moreover, the catalytic performance achieved at 10 mA cm-2 is comparable or even better than that of most transition metal silicates/oxides/hydroxides. The findings indicate that the incorporation of phosphate into the structure of CoSi can enhance its OER performance. This study not only provides a non-noble metal catalyst CoSi-P but also demonstrates that the incorporation of phosphates into transition metal silicates (TMSs) offers a promising strategy for the design of robust, high-efficiency, and low-cost OER catalysts.
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  • 文章类型: Journal Article
    外延Pr0.1Ce0.9O2-δ电极的氧交换动力学通过修饰亚单层量的不同碱性(SrO,CaO)和酸性(SnO2,TiO2)二元氧化物。通过原位PLD阻抗谱(i-PLD)测量氧交换反应(OER)速率和总电导率,这允许在每个沉积的表面装饰脉冲后直接跟踪电化学性能的变化。通过高温下的近环境压力XPS测量(NAP-XPS)和低能离子散射(LEIS)研究了电极的表面化学。虽然用二元氧化物装饰后观察到OER率的显著变化,表面交换电阻的pO2依赖性及其活化能不受影响,这表明表面装饰不会改变基本的OER机制。此外,薄膜的总电导率在装饰时不会改变,表明缺陷浓度变化仅限于表面层。这通过NAP-XPS测量得到证实,其在装饰时仅发现Pr-氧化态的微小变化。NAP-XPS进一步用于研究装饰表面上表面电势阶跃的变化。从机械的角度来看,我们的结果表明,表面电势和改变的氧交换活性之间存在相关性。氧化装饰诱导表面电荷,这取决于它们的酸度(酸性氧化物导致负表面电荷),影响表面缺陷浓度,任何现有的表面电位步骤,潜在的吸附动力学,因此也是OER动力学。
    The oxygen exchange kinetics of epitaxial Pr0.1Ce0.9O2-δ electrodes was modified by decoration with submonolayer amounts of different basic (SrO, CaO) and acidic (SnO2, TiO2) binary oxides. The oxygen exchange reaction (OER) rate and the total conductivity were measured by in situ PLD impedance spectroscopy (i-PLD), which allows to directly track changes of electrochemical properties after each deposited pulse of surface decoration. The surface chemistry of the electrodes was investigated by near-ambient pressure XPS measurements (NAP-XPS) at elevated temperatures and by low-energy ion scattering (LEIS). While a significant alteration of the OER rate was observed after decoration with binary oxides, the pO2 dependence of the surface exchange resistance and its activation energy were not affected, suggesting that surface decorations do not alter the fundamental OER mechanism. Furthermore, the total conductivity of the thin films does not change upon decoration, indicating that defect concentration changes are limited to the surface layer. This is confirmed by NAP-XPS measurements which find only minor changes of the Pr-oxidation state upon decoration. NAP-XPS was further employed to investigate changes of the surface potential step on decorated surfaces. From a mechanistic point of view, our results indicate a correlation between the surface potential and the altered oxygen exchange activity. Oxidic decorations induce a surface charge which depends on their acidity (acidic oxides lead to a negative surface charge), affecting surface defect concentrations, any existing surface potential step, potentially adsorption dynamics, and consequently also the OER kinetics.
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  • 文章类型: Journal Article
    具有双极特性的p-n结设置了基本单元来构建电子器件,而其独特的整流行为限制了扩展功能的载流子可调性程度。在这里,报告了在电解质中运行的与氮化镓(GaN)p-n同质结纳米线阵列一起使用的双极结光电极,展示了由不同波长的光控制的双极光响应。重要的是,在理论建模的指导下,对纳米线上的氧化钌(RuOx)层进行合理装饰,所得的RuOx/p-nGaN光电极表现出明确的增强的双极光响应,对正负光电流增强了775%和3000%,分别,与原始纳米线相比。纳米线表面上RuOx层的负载优化了表面带弯曲,这促进了跨GaN/电解质界面的电荷转移,同时提高了对应于负和正光电流的析氢反应和析氧反应的氧化还原反应效率,分别。最后,本发明公开了一种双通道光通信系统,该双通道光通信系统结合了这种光电极,仅使用一个光电极来解码具有加密特性的双频带信号。所提出的双极器件架构提供了一种可行的途径来操纵载流子动力学,以开发过多的多功能光电器件,用于未来的传感。通信,和成像系统。
    The p-n junction with bipolar characteristics sets the fundamental unit to build electronics while its unique rectification behavior constrains the degree of carrier tunability for expanded functionalities. Herein, a bipolar-junction photoelectrode employed with a gallium nitride (GaN) p-n homojunction nanowire array that operates in electrolyte is reported, demonstrating bipolar photoresponse controlled by different wavelengths of light. Significantly, with rational decoration of a ruthenium oxides (RuOx ) layer on nanowires guided by theoretical modeling, the resulting RuOx /p-n GaN photoelectrode exhibits unambiguously boosted bipolar photoresponse by an enhancement of 775% and 3000% for positive and negative photocurrents, respectively, compared to the pristine nanowires. The loading of the RuOx layer on nanowire surface optimizes surface band bending, which facilitates charge transfer across the GaN/electrolyte interface, meanwhile promoting the efficiency of redox reaction for both hydrogen evolution reaction and oxygen evolution reaction which corresponds to the negative and positive photocurrents, respectively. Finally, a dual-channel optical communication system incorporated with such photoelectrode is constructed with using only one photoelectrode to decode dual-band signals with encrypted property. The proposed bipolar device architecture presents a viable route to manipulate the carrier dynamics for the development of a plethora of multifunctional optoelectronic devices for future sensing, communication, and imaging systems.
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  • 文章类型: Journal Article
    由于纳米载体(NCs)可以提高药物的溶解度,防止它们被胃肠道(GI)酶降解,并促进它们穿过粘液凝胶层和吸收膜的运输,这些药物的口服生物利用度可以显著提高。NCs的所有这些特性,包括自乳化给药系统(SEDDS),固体脂质纳米粒(SLN),纳米结构脂质载体(NLCs),脂质体,聚合物纳米颗粒,无机纳米粒子和聚合物胶束主要取决于它们的表面化学。特别是,与食物的互动,消化酶,胆汁盐和电解质,通过粘液凝胶层的扩散行为和吸收膜上的命运取决于它们的表面。生物惰性表面限制与胃肠液和内容物以及粘液的相互作用,可设计提供与GI粘膜紧密接触的粘合表面和吸收增强表面。此外,电荷转换表面直接在吸收膜和提供靶向药物释放的表面处将它们的ζ电位从负转变为正是有利的。除了这些被动表面,甚至在通过粘液凝胶层的途中切割粘液糖蛋白的活性表面也可以被创建。在这次审查中,我们对这些不同的表面进行了概述,并讨论了它们对胃肠道中NC性能的影响。
    As nanocarriers (NCs) can improve the solubility of drugs, prevent their degradation by gastrointestinal (GI) enzymes and promote their transport across the mucus gel layer and absorption membrane, the oral bioavailability of these drugs can be substantially enhanced. All these properties of NCs including self-emulsifying drug delivery systems (SEDDS), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), liposomes, polymeric nanoparticles, inorganic nanoparticles and polymeric micelles depend mainly on their surface chemistry. In particular, interaction with food, digestive enzymes, bile salts and electrolytes, diffusion behaviour across the mucus gel layer and fate on the absorption membrane are determined by their surface. Bioinert surfaces limiting interactions with gastrointestinal fluid and content as well as with mucus, adhesive surfaces providing an intimate contact with the GI mucosa and absorption enhancing surfaces can be designed. Furthermore, charge converting surfaces shifting their zeta potential from negative to positive directly at the absorption membrane and surfaces providing a targeted drug release are advantageous. In addition to these passive surfaces, even active surfaces cleaving mucus glycoproteins on their way through the mucus gel layer can be created. Within this review, we provide an overview on these different surfaces and discuss their impact on the performance of NCs in the GI tract.
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