Etching characteristics of thin SiON films using a liquefied perfluorocarbon precursor of C_6F_(12)O with a low global warming potential

Perfluorocarbon gas is widely used in the semiconductor industry.However,perfluorocarbon has a negative effect on the global environment owing to its high global warming potential(GWP) value.An alternative solution is essential.Therefore,we evaluated the possibility of replacing conventional perfluorocarbon etching gases such as CHF_3 with C_6F_(12)O,which has a low GWP and is in a liquid state at room temperature.In this study,silicon oxynitride(SiON) films were plasma-etched using inductively coupled CF4+C_6F_(12)O+O_2 mixed plasmas.Subsequently,the etching characteristics of the film,such as etching rate,etching profile,selectivity over Si,and photoresist,were investigated.A double Langmuir probe was used and optical emission spectroscopy was performed for plasma diagnostics.In addition,a contact angle goniometer and x-ray photoelectron spectroscope were used to confirm the change in the surface properties of the etched SiON film surface.Consequently,the etching characteristics of the C_6F_(12)O mixed plasma exhibited a lower etching rate,higher SiON/Si selectivity,lower plasma damage,and more vertical etched profiles than the conventional CHF_3 mixed plasma.In addition,the C_6F_(12)O gas can be recovered in the liquid state,thereby decreasing global warming.These results confirmed that the C_6F_(12)O precursor can sufficiently replace the conventional etching gas.

Microscopic mechanism of perfluorocarbon gas formation in aluminum electrolysis process

In view of the unclear cause of perfluorocarbons(PFCs)emission in the anode effect stage of aluminum electrolysis,the microscopic formation mechanism of PFCs was studied by density functional theory calculation and X-ray photoelectron spectroscopy(XPS).It is found that the discharge of fluorine containing anions([F]−)on carbon anode first causes the substitution of C—H by C—F and further results in the saturation of aromatic C—C bonds,leading to the appearance of—CF_(3)or—C_(2)F_(5)group through six-carbon-ring opening.Elimination of—CF_(3)and—C_(2)F_(5) with F atom could be a likely mechanism of CF_(4) and C_(2)F_(6) formation.XPS results confirm that different types of—CF_(x) group can be formed on anode surface during electrolysis,and the possibility that[F]−discharges continuously at the C edge and finally forms different C—F bonds in quantum mechanical calculation was verified.

Recent Advances in ^(19)Fluorine Magnetic Resonance Imaging with Perfluorocarbon Emulsions

The research roots of 19fluorine （19F） magnetic resonance imaging （MRI） date back over 35 years. Over that time span, 1H imaging flourished and was adopted worldwide with an endless array of applications and imaging approaches, making magnetic resonance an indispensable pillar of biomedical diagnostic imaging. For many years during this timeframe, 19F imaging research continued at a slow pace as the various attributes of the technique were explored. However, over the last decade and particularly the last several years, the pace and clinical relevance of 19F imaging has exploded. In part, this is due to advances in MRI instrumentation, ~gF/1H coil designs, and ultrafast pulse sequence development for both preclinical and clinical scanners. These achievements, coupled with interest in the molecular imaging of anatomy and physiology, and combined with a cadre of innovative agents, have brought the concept of ~gF into early clinical evaluation. In this review, we attempt to provide a slice of this rich history of research and development, with a particular focus on liquid perfluorocarbon compound-based agents.

New technique for removal of perfluorocarbon liquid related sticky silicone oil and literature review

AIM:To investigate the safety and efficacy of sticky silicone oil(SSO)removal using a 22-gauge vein detained needle and inner limiting membrane(ILM)wrap-and-peel technique.METHODS:This retrospective consecutive case series reviewed the records of patients with a history of retinal detachment who had received silicone oil and perfluorocarbon liquid(PFCL)as intraocular tamponades.Patients were included in the analysis if they exhibited SSO remnants during silicone oil removal.The aspiration of most of the SSO remnants was performed by a 22-gauge vein detained needle.The small amounts of droplets adhered to the macula and epi-macular membrane were subsequently removed by the ILM warp-and-peel technique.The anatomical and functional outcomes,and postoperative complications were recorded.In vitro experiments were performed to simulate the formation of SSO remnants in four groups.RESULTS:Of 711 patients who underwent silicone oil removal during the study period,9 patients exhibited SSO remnants and underwent follow-up for at least 3mo.Seven eyes(78%)underwent the ILM wrap-and-peel technique to completely remove small droplets of SSO that were glued to the macula and epi-macular membrane.No obvious complications occurred.Postoperative optical coherence tomography revealed normal retinal structure in all patients.In vitro analyses showed that balanced salt solution and prolonged vibration(for 1wk)had the strongest effects on silicone oil and PFCL compound opacities.CONCLUSION:SSO remnants could be removed in an intact manner and without complications,using a vein detained needle-assisted and ILM wrap-and-peel technique.The findings suggest that PFCL and infusion fluid should be completely removed before silicone oil injection to prevent SSO formation.

A surprising visual improvement following a prolonged 5-month retained subfoveal perfluorocarbon liquid

Dear Sir,I am Dr.Daniel Ting,from the Department of Ophthalmology,Singapore National Eye Centre,Singapore.I write to present a case of a surprising significant visual improvement following a prolonged 5-month retained subfoveal perfluorocarbon liquid.Retained perfluorocarbon liquid（PFCL）has been shown to cause decreased visual acuity,retinal pigment epithelial（RPE）toxicity,retinal degeneration and gravity deformation ,

Use of Perfluorocarbon Liquids in Complicated Retinal Detachments

We now have an additional tool to help in managing complicated retinal detachments. We look forward to the day when we can leave the liquid without having to remove it because of the possibility of ocular complications.

Ginsenoside modified lipid-coated perfluorocarbon nanodroplets: A novel approach to reduce complement protein adsorption and prolong in vivo circulation

Lipid-coated perfluorocarbon nanodroplets(lp-NDs)hold great promise in bio-medicine as vehicles for drug delivery,molecular imaging and vaccine agents.However,their clinical utility is restricted by limited targeted accumulation,attributed to the innate immune system(IIS),which acts as the initial defense mechanism in humans.This study aimed to optimize lp-ND formulations to mini-mize non-specific clearance by the IIS.Ginsenosides(Gs),the principal components of Panax ginseng,possessing complement inhibition ability,structural similarity to cholesterol,and comparable fat solubi-lity to phospholipids,were used as promising candidate IIS inhibitors.Two different types of ginsenoside-based Ip-NDs(Gs Ip-NDs)were created,and their efficacy in reducing IS recognition was examined.The Gs p-NDs were observed to inhibit the adsorption of C3 in the protein corona(PC)and the generation of SC5b-9.Adding Gs to Ip-NDs reduced complement adsorption and phagocytosis,resulting in a longer blood circulation time in vivo compared to lp-NDs that did not contain Gs.These results suggest that Gs can act as anti-complement and anti-phagocytosis adjuvants,potentially reducing non-specific clear-ance by the IS and improving lifespan.

太浦河水体和沉积物中24种全氟化合物分布特征

本研究以24种全氟化合物(polyfluoroalkyl substances,PFASs)为研究对象,于冬、夏两季采集了太浦河流域重要点位的水样以及沉积物,并采用固相萃取、液液萃取联合高效液相色谱-串联质谱(HPLC/MS-MS)的方法,探讨PFASs在太浦河流域水环境中的时空分布特征以及分配行为.结果显示,水体中PFASs的总质量浓度范围在114.24—168.62 ng·L^(-1),主要的污染物为全氟丁酸(PFBA)和全氟辛酸(PFOA),平均浓度为24.92 ng·L^(-1)和28.18 ng·L^(-1);沉积物中ΣPFASs在2.36—4.73 ng·g^(-1)(dw,干重),主要的污染物为全氟十一酸(PFUdA)和全氟十二酸(PFDoA),平均浓度为0.78 ng·g^(-1)(dw)和0.52 ng·g^(-1)(dw).水样的监测结果显示,各点位PFASs总浓度波动不大,仅在个别点位出现PFASs突增的情况.PFASs在太浦河流段没有明显的季节性差异,这与今年夏季降雨量少的情况有关.PFASs在沉积物-水的分配行为表明,PFASs在沉积物-水的分配系数与总有机碳(total organic carbon,TOC)的含量、PFASs碳链长度以及PFASs官能团结构有关.短链PFASs主要存在于水体中,长链PFASs则主要分布在沉积物中;全氟磺酸类(PFSAs)较全氟羧酸类(PFCAs)更易吸附在沉积物中.对PFASs来源解析发现:水体中PFASs的来源包括了外源输入和点源排放,夏季河体内PFASs主要受到大气远距离传输影响,冬季则与河道周围的工业活动有关.

Perfluorocarbon attenuates lipopolysaccharide-mediated inflammatory responses of alveolar epithelial cells in vitro

Background Toll-like receptor-4 （TLR-4） is integrally involved in lipopolysaccharide （LPS） signaling and has a requisite role in the activation of nuclear factor-κB （NF-κB）. The exact mechanisms that lend perfluorocarbon （PFC） liquids a cytoprotective effect have yet to be elucidated. Therefore we examined in an in vitro model the cytoprotective effect of PFC on LPS-stimulated alveolar epithelial cellls （AECs）. Methods AECs （A549 cells, human lung adenocarcinoma cell line） were divided into four groups： control, PFC, LPS and LPS ＋ PFC （coculture group） groups. Intercellular adhesion molecule-1 （ICAM-1） was detected by ELISA, tumor necrosis factor-g （TNF-a） and interleukin-8 （IL-8） were detected by radioimmunological methods. The expression of TLR-4 mRNA and protein was detected by real time PCR and Western blotting, respectively. The activation of NF-κB was detected by Western blotting （proteins of I-κBa and NF-κB p65）. Results ICAM-1, TNF-a and IL-8 were significantly increased in LPS-stimulated AECs groups. The expression of TLR-4 mRNA and protein in LPS-stimulated groups was markedly increased. Meanwhile, NF-κB was activated as indicated by the significant degradation of IKB-a and the significant release of NF-κB P65 and its subsequent translocation into the nucleus. There were no significant effects of PFC alone on any of the factors studied while the coculture group showed significant downregulation of the secretion of ICAM-1, TNF-a and IL-8, the expression of TLR-4 rn^NA and the activity of NF-κB. Conclusions Taken together, our results demonstrate that LPS can induce AEC-related inflammatory injury via the activation of TLR-4 and subsequent activation of NF-κB. PFC is able to protect AECs from LPS-induced inflammatory injury by blocking the initiation of the LPS signaling pathway, which is indicated by the significant decrease of TLR-4 expression and NF-κB activation.

Facile Synthesis of Novel Perfluorocarbon-Modulated 4-Anilinoquinazoline Analogues

4-Anilinoquinazoline analogues stand out among many kinds of small molecules that inhibit the tyrosine kinase activities of epidermal growth factor receptor （EGFR）, thus serving as significant molecular targets for anticancer drug design. Herein, a series of novel perfluorocarbon （PFC） modulated 4-anilinoquinazolines were designed and prepared straightforwardly by nucleophilic substitution reaction of various anilinoquinazolines and PFC-derived methanesulfonate. In the presence of base, the reaction proceeded smoothly to afford a wide range of 4-anilino- quinazolines with different substituents on aniline moiety in good to high yields. Furthermore, the PFC-modified analogues of gefitinib and erlotinib were also obtained in 93% and 90% respectively, which may have potential for developing new inhibitors of the epidermal growth factor receptor （EGFR） tyrosine kinase and fluorinated contrast agents （CA） for 19F MRI.

A new method for concentration analysis of bacterial endotoxins in perfluorocarbon

This communication demonstrates the feasibility of the gel-clot method for the analysis of bacterial endotoxins in water extracts of perfluorocarbon which is a water insoluble liquid medical device. Perfluorocarbon （10 mL） was shaken with 10 mL water for 15 min at 2000 r/min and the endotoxin present was extracted to the aqueous phase without interference inhibition/enhancement of the product and the recovery of endotoxin added to perfluorocarbon was determined, A validation study confirmed that endotoxins presented in perfluorocarbon pass over into the aqueous phase at concentrations of 20, 10 and 5EU/mL with recoveries from 86.8% to 96.8%. Therefore, the gel-clot test is suitable for detecting bacterial endotoxins in perfluorocarbon which is a water insoluble medical device.

Color-coded perfluorocarbon nanodroplets for multiplexed ultrasound and photoacoustic imaging

Laser-activated perfluorocarb on n anodroplets are an emerging class of phase-cha nge, dual-c ontrast age nts that can be utilized in ultraso und and photoacoustic imaging. Through the ability to differe ntiate subpopulations of nano droplets via laser activatio n at differe nt wavelengths of n ear-infrared light, optically-triggered color-coded perfluorocarb on nano droplets prese nt themselves as an attractive tool for multiplexed ultrasound and photoacoustic imaging. In particular, laser-activated droplets can be used to provide quantitative spatiotemporal information regarding distinct biological targets, allowing for their potential use in a wide range of diagnostic and therapeutic applications. In the work prese nted, laser-activated color-coded perfluorocarb on nan odroplets are syn thesized to selectively resp ond to laser irradiati on at corresp on ding wavele ngths. The dyn amic ultraso und and photoacoustic signals produced by laser-activated perfluorocarbon nano droplets are evaluated in situ prior to implementation in a murine model. In vivo, these particles are used to distinguish unique particle trafficking mechanisms and are show n to provide ultraso und and photoacoustic contrast for up to 72 hours within lymphatics. Overall, the con ducted studies show that laser-activated color-coded perfluorocarbo n nano droplets are a promising agent for multiplexed ultraso und and photoacoustic imaging.

全氟化碳雾化吸入对大鼠海水吸入性肺损伤治疗作用研究

背景海水吸入性肺损伤是呼吸系统危重症,致死率高,目前缺乏有效治疗方法。全氟化碳(perfluorocarbon,PFC)是一种无色无味呈惰性的有机化合物,在多种急性肺损伤动物模型中表现出抗炎、抗氧化、减轻肺损伤等作用,目前无PFC雾化吸入对海水淹溺导致的急性肺损伤干预作用的研究。目的本研究拟探讨PFC雾化吸入对海水吸入性肺损伤的治疗作用。方法32只雄性SD大鼠随机分为4组,分别为0.9%氯化钠注射液组(N组)、全氟化碳雾化吸入组(P组)、海水吸入+0.9%氯化钠注射液吸入组(SW组)、海水吸入+PFC雾化吸入组(SP组),每组8只。SW组和SP组在建立海水吸入性肺损伤模型后30 min,分别经气管给予0.9%氯化钠注射液(2 mL/kg)和PFC(2 mL/kg)雾化吸入。于建模后4 h取肺组织、外周血和肺泡灌洗液,检测组织病理学、炎症指标[肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、白细胞介素(interleukin,IL)-1β、IL-6]、氧化应激指标[髓过氧化物酶(myeloperoxidase,MPO)、丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)]、肺湿干比、肺泡灌洗液蛋白浓度,取右下肺做HE染色。另取16只雄性SD大鼠,分为4组,每组4只(各组处理方式同上),各组于处死前30 min经右侧股静脉注射2%伊文斯蓝染料(20 mg/kg),测定肺组织伊文斯蓝含量。结果与N组相比,SW组肺损伤较重,肺损伤病理评分较高(P<0.05),血清及肺泡灌洗液TNF-α、IL-1β、IL-6、MDA、MPO、肺组织湿干比、肺泡灌洗液蛋白含量及肺组织伊文斯蓝水平显著升高(P<0.05),SOD含量降低(P<0.05)。海水吸入后给予PFC雾化吸入,可显著降低肺损伤病理评分、血清及肺泡灌洗液TNF-α、IL-1β含量、肺泡灌洗液IL-6、血清MDA、蛋白含量、湿干比、肺组织伊文斯蓝含量(P<0.05),SOD含量显著升高(P<0.05),而血清IL-6、MPO在SW组与SP组间无统计学差异。结论全氟化碳雾化吸入可显著减轻大鼠海水吸入导致的肺损伤,其机制可能与改善肺内炎症反应、氧化应激和肺泡毛细血管通透性有关。

基于穿流式的电催化氧化降解全氟化合物的研究进展

全氟化合物(PFCs)因具有强稳定性、疏水疏油性、高表面活性等而被广泛应用,其远距离迁移及高水溶性加剧了水体污染,如何高效低耗处理含氟废水已成为水处理领域亟待解决的难题。其中,电催化氧化技术因其高效清洁、易操作、自动化程度高等优势,被广泛应用于PFCs的处理。而基于穿流式的电催化膜电极发挥了滤膜、电极和催化三重作用,解决了传统电催化氧化系统中传质传荷受限、活性物种利用率低、高能耗等难题,对PFCs深度降解研究意义重大。基于此,主要介绍不同类型电极对PFCs的降解,着重针对穿流式电催化氧化系统进行介绍,包括技术发展历程、膜材料、反应器类型等,探讨其强化机制、PFCs的降解机理和电催化膜电极污染防控策略,并对该技术的未来发展趋势进行总结展望。

全氟化碳纳米乳在肿瘤诊疗中的研究进展

全氟化碳(PFC)纳米乳广泛应用于肿瘤的诊疗中,其PFC核心不仅能向肿瘤环境递送氧气,缓解肿瘤微环境缺氧状态,提高氧依赖性治疗方式的疗效,同时也可以在高能量的激发下发生从气态到液态的转变,应用于肿瘤成像和药物递送。本文综述了PFC纳米乳在肿瘤治疗和诊断中的研究进展,系统总结了PFC纳米乳分类以及在肿瘤治疗和诊断方面的应用,并提出了目前仍存在的一些问题及未来的研究方向。

铝电解生产过程全氟化碳排放现状与分析

全氟化碳(PFCs)是目前被认为增温潜势非常强的温室气体,铝电解生产过程中产生的全氟化碳包括CF_(4)和C_(2)F_(6)。我国电解铝产量连续十多年位居世界首位,降低铝电解生产过程中PFCs排放是铝工业温室气体减排的路径之一。本文分析了铝电解PFCs的产生机理和排放情况,并以某企业300 kA系列电解槽为例,测量计算其PFCs的CO_(2)当量排放,并与按照指南缺省值核算的PFCs排放数据进行对比。对比结果表明,按缺省值计算的PFCs排放量为0.2523 t CO_(2)e/t-Al,远小于测量值0.8839 t CO_(2)e/t-Al,无法体现企业的真正PFCs排放情况。根据铝电解析出碳氟化合物的反应机理,降低铝电解生产PFCs排放的直接途径是减少阳极效应次数和缩短效应时间。因此,为了减少PFCs排放,从电解槽优化设计、槽控系统升级、工艺技术优化、大宗原料把控、设备运行维护等建方面提出了建议。

基于全氟化碳的人工氧载体研究进展

全氟化碳是一种具有良好生物相容性的化学惰性物质,已广泛应用于超声造影、器官移植、预防组织器官缺血和再灌注损伤等。全氟化碳纳米乳剂具有高携氧能力,是人工氧载体研究关注的焦点,但因全氟化碳易挥发、不易溶解、乳化后稳定性差等,其纳米乳剂研发成功者极少。本文对全氟化碳纳米乳剂的研究进展进行综述,对影响乳剂稳定性的因素进行分析探讨并提出可能对策,为获得稳定的全氟化碳人工氧载体提供借鉴和参考。

Electrochemical behavior of graphite anode during anode effect in cryolite molten salts

Anodic electrochemical behavior was studied on graphite anode at 1000 ℃ in cryolite-alumina molten salt by means of cyclic voltammetry. The high current peak in a typical cyclic voltammogram was discussed. It is considered that a type of oxyfluoroaliminate complex anions reacts with carbon to form a high-resistance CF film on the anode surface at a high potential. The passivation potential is 3.28 V in 0.5% alumina-containing electrolyte, and the passivation potential increases with alumina content increasing which indicates that the alumina content determines the anodic process in the cryolite-alumina molten salt system.

纳米液态氟碳脂质微球超声造影剂的制备及体外聚集实验研究

目的制备一种新型超声造影剂——纳米液态氟碳脂质微球造影剂,并研究其体外基本特性及聚集后增强超声显影性能。方法采用高压均质法制备纳米液态氟碳脂质微球超声造影剂,检测一般理化性质,再制备生物素化微球,以空白微球为对照组,分别在加入亲和素前后,观察体外聚集情况及超声显影效果,并用DFY超声图像定量分析统计软件计算、比较超声图像平均灰度值。结果所制备的液态氟碳脂质微球为外观呈乳白色的混悬液,镜下微球形态圆整,大小均一,性质稳定,粒径(171.9±91.0)nm;制备的生物素化微球在加入亲和素后聚集成团状,并可增强超声显影,经DFY软件分析,加入亲和素前后超声图像平均灰度值差异有统计学意义。结论成功制备出稳定的纳米液态氟碳脂质超声造影剂,并采用生物素亲和素法证明了该微球具有聚集后增强超声显影性能。

叶酸受体靶向高分子相变超声造影剂的制备及体外寻靶实验研究

目的制备一种叶酸受体靶向的相变超声造影剂,观察其体外细胞靶向效果及超声显影情况。方法采用单乳化法制备包裹液态氟碳的高分子纳米微球,通过碳二亚胺法连接叶酸配体制备叶酸受体靶向的相变超声造影剂,以人卵巢癌SKOV3细胞验证其体外细胞靶向性能,以高强度聚焦超声(HIFU)体外辐照实验观察其超声显影情况。结果所制备叶酸受体靶向高分子相变超声造影剂平均粒径为(229.13±13.46)nm,体外细胞寻靶实验显示靶向造影剂与SKOV3细胞大量结合,而普通造影剂组与游离叶酸干预组未见明显特异性结合。造影剂溶液经一定功率HIFU辐照后,超声显影效果较辐照前明显增强。结论成功制备了叶酸受体靶向包裹液态氟碳的高分子造影剂,对高表达叶酸受体的SKOV3细胞具有良好靶向性,并具备HIFU辐照后增强超声显影的特性,有望成为卵巢癌靶向显影与治疗的理想分子探针。