烟台地区氟中毒的环境因素分析

介绍氟中毒的症状以及发病机理。对烟台地区氟中毒的引发因素进行了综述。从土壤与母质、地形、地貌、岩性与矿物成分、水化学类型、地下水温度、气候及饮食状况等多个方面对烟台地区发生的氟中毒进行环境因素分析,分别阐述了各个因子的特征与该地区发病情况的关系。根据引发烟台地区氟中毒的环境因素提出防治氟中毒的对策。     

改水七年后氟骨症患者尿羟脯氨酸和氟等元素排泄量分析

分析了改饮低氟水七年后氟骨症患者尿氟、钙、镁、铜、锌、锰六种元素和尿羟脯氨酸的排泄量。结果表明，氟骨症患者与非病区正常人群对比，除尿氟明显升高和尿钙降低外，蓁各项指标均无 统计学上有意义的差异。提示氟骨症患者脱离高氟环境后，骨骼蓄积的氟化物可缓慢持久地从尿中排出，随着机体氟含理的减少，原有的胶原代谢紊乱被逐渐纠正而恢复正常。     

鸡铝氟联合中毒模型及其比较实验研究

制作和研究了病家雏鸡铝氟联合中毒模型,用100日龄雄性种鸡84只随机分为7组,病区玉米及毒物加入饲料自由进食。实验期3个月。结果表明,各实验组均有2～5只典型骨软化的鸡,并都出现小细胞性盆血。饲氟170×10     

硒对氟中毒大鼠尿氟及脑肾组织脂质过氧化物含量的影响

大鼠饲料分别加入２×１０－６、４×１０－６硒．饮用７．５×１０－６、１５×１０－６氟水．１个月后，随尿硒粪硒排量增加，尿氟排量也增高，以２×１０－６硒饲料排氟效果最佳．血浆中ＡＬＰ、ＧＯＴ、ＧＰＴ及ＬＤＨ等酶活性加硒组有不同程度的降低．随后两次增高氟水量重复试验，给以２×１０－６硒饲料，仍观察到尿氟排量增高．血中含硒酶谷胱甘肽过氧化物酶活性也有升高趋势，脑及肾中脂质过氧化物（ＬＰＯ）含量明显减少，病区患者服硒后，尿氟含量亦高于对照组．实验结果提示；１）硒能促使体内氟由尿中排出；２）降低某些组织ＬＰＯ含量；３）减少体内氟含量；４）预防和改善氟中毒某些临床症状。     

氟作业工人骨骼X线改变的分析

对９６６名氟作业工人选定的骨骼常规摄Ｘ光片,按其不同日摄氟量分组观片、记录。结果显示：①骨骼Ｘ线改变阳性率与日摄氟量呈正相关（ｒ＝０．８７９,Ｐ〈０．０１）;②不同部位的骨骼Ｘ线改变阳性率有差异;③骨骼Ｘ线改变的主要表现是骨密度增高、骨间膜增宽或钙化、关节、骨周、髓腔有改变、骨质增生、闭孔膜及韧带钙化等。     

煤烘玉米铝氟联合中毒病区环境因素的调查

为探讨氟中毒重病区铝危害情况 ,给该病防治提供依据 ,在分析贵州已查明的 4个经骨X线诊断有骨软化或残留骨变形氟重病区病人血、尿、头发铝含量的同时 ,对相关环境和物质进行了调查和检测。各重病区均在一定的地理、地质环境中 ;主粮均为玉米 ,必须及时干燥 ,习惯用原煤或原煤加粘土烘干并长期烘炕 ,以防发芽、霉烂和回潮变质。原煤、拌煤粘土、沉积烟尘含氟量均很高 ,其烘炕的玉米氟含量增高数十倍到成百倍 ,达 42× 10 -6～ 13 5× 10 -6,铝增高数倍 ,达 3 2× 10 -6～ 5 5× 10 -6。不同煤质燃烧时厨房空气氟含量可相差数倍 ,玉米氟含量相差数倍到 10数倍 ,其食用人群有不同的病情。采取综合措施使玉米含氟 <10× 10 -6可避免铝危害的骨软化残废性畸形的发生     

氟骨症对人体的损害

氟是人体必不可少的微量元素之一。人体如从外界环境中获得的氟超过正常的需要，就可发生氟中毒。地方性氟中毒是由于长期饮用高氟水及含氟量较多的食物引起的，是一种慢性全身性疾病。氟沉积于牙齿上称为氟斑牙，或称斑釉病；沉积于骨骼上即称为氟骨症。不仅是人，牛马等牲畜也可因氟中毒而失去役使能力。     

氟元素在人体中表现的两面性

主要从氟的化学性质来分析氟元素在生活中的利弊,从而介绍我们在生活中对于氟的补充或者摄入时应该注意的问题。     

铝氟联合中毒暨铝引起少儿钙磷铁锌生物有效利用不良综合征

对某村普查筛出的铝氟联合中毒病人及高氟,高氟铝、高铝的实验种鸡进行动态研究。结果表明,氟含量〉４０＊１０＾－６的主食玉米促成了一般摄铝浓度人群的铝吸收和蓄积,饲铝超过一般浓度１－４倍的童鸡便有肝、肾铝蓄积、骨铝反而显著下降,但均出现低龄人群和实验动物的高钙血和高骨矿性骨营养不良软化,高全血磷的ＡＴＰ生成减少,全血铁增高的缺铁性小细胞性贫血,低锌症,智能和体能下等钙磷铁锌生物有 良和低素质综合症,随     

金华市地氟病病区摄氟总量调查

金华地区氟污染严重,地氟病病区居民摄氟总量偏高,平均日摄入量可达4.77 mg。饮水和食物是主要的摄氟途径。应该采用综合性的地氟病防治措施,仅仅靠改水是不够的。     

土壤中化学元素与地氟病的生态学比较研究

为了解地氟病区土壤化学元素异常分布情况,给全面查找地氟病病因提供依据,采用生态学比较研究对各乡镇患病率与土壤化学元素水平做了相关分析.结果表明,巫山县土壤中铅、镍、氟、pH 与患病率有较弱的正相关关系;奉节县土壤中汞、镍与患病率有较弱的正相关关系.巫山县土壤氟和碘分别是其背景值的1.84、2.89倍,患病率高达65.3...     

土壤氟与植物

氟是人体必需微量元素,其丰缺与人体健康息息相关。土壤在地理环境中的特殊地位决定着土壤氟对生态环境的特殊意义。土壤氟(特别是土壤水溶性氟)与植物体的氟含量密切相关,从而也与人体健康密切相关。不同植物对氟的富集程度不同,蔬菜(特别是叶菜)对土壤氟的富集程度很高,是造成地氟病的重要因素。     

治疗256例氟斑牙（着色型）分析

以不同比例浓盐酸与30％过氧化氢混合溶液治疗了256例着色型氟斑牙患者，有效率为98．71％、中度95．15％、重度92．35％。     

Lower friction and higher wear resistance of fluorine‐incorporated amorphous carbon films

Plasma‐enhanced chemical vapor deposition was employed to fabricate hydrogenated amorphous carbon (a‐C:H) films and fluorine‐doped hydrogenated amorphous (a‐C:H:F) carbon films. For comparison purpose, the a‐C:H films were treated with CF₄ plasma. The bonding structure and tribological behavior of the films were investigated. The results indicate that the F presented mainly in the forms of C–F₃, C–F and C–F₂ groups in both the a‐C:H:F film and the surface CF₄ plasma processed hydrogenated amorphous carbon (F‐P‐a‐C:H) films. Moreover, the a‐C:H:F films, because of the transformation of sp³ to sp², possess a lower friction coefficient than that of the F‐P‐a‐C:H films. Copyright © 2013 John Wiley & Sons, Ltd.     

Crystal structure and thermal chemical properties of 2-(2,4-dimethylanilino)-3-methyl-6-diethylaminofluorane

The crystal structure of 2-(2,4-dimethylanilino)-3-methyl-6-diethylaminofluorane has been determined by single crystal X-ray diffraction method. The crystal belongs to triclinic system, space group P-1 with unit cell constants a = 11.2877(9) Å, b = 11.9539(9) Å, c = 12.2365(9) Å, α = 97.2580(10)°, β = 116.2850(10)°, γ = 106.3710(10)°, V = 1358.48(18) Å ³, Z = 2, D _c = 1.234 g/cm³, μ = 0.079 mm^?1, F(000) = 536, R and w(R) are 0.0718 and 0.2055, respectively, for 5239 unique reflections with 3745 observed reflections (I > 2σ(I)).     

Synthesis and Conformational Analysis of Fluorinated Uridine Analogues Provide Insight into a Neighbouring-Group Participation Mechanism

Fluorinated nucleoside analogues have attracted much attention as anticancer and antiviral agents and as probes for enzymatic function. However, the lack of direct synthetic methods, especially for 2′,3′-dideoxy-2′,3′-difluoro nucleosides, hamper their practical utility. In order to design more efficient synthetic methods, a better understanding of the conformation and mechanism of formation of these molecules is important. Herein, we report the synthesis and conformational analysis of a 2′,3′-dideoxy-2′,3′-difluoro and a 2′-deoxy-2′-fluoro uridine derivative and provide an insight into the reaction mechanism. We suggest that the transformation most likely diverges from the S_N1 or S_N2 pathway, but instead operates via a neighbouring-group participation mechanism.     

UF4 and the High-Pressure Polymorph HP-UF4

A laboratory-scale synthesis of UF₄ is presented that utilizes the reduction of UF₆ with sulfur in anhydrous hydrogen fluoride. An excess of sulfur can be removed by vacuum sublimation, yielding pure UF₄, as shown by powder X-ray diffraction, micro X-ray fluorescence analysis, infrared and Raman spectroscopy, as well as magnetic measurements. Furthermore, a single-crystalline, high-pressure modification of UF₄ was obtained in a multi-anvil press at elevated temperatures. The high-pressure polymorph HP-UF₄ was characterized by means of single-crystal and powder X-ray diffraction, as well as by magnetic measurements, and presents a novel crystal structure type. Quantum-chemical calculations show the HP-modification to be 10 kJ mol⁻¹ per formula unit higher in energy compared to UF₄.     

含氟聚丙烯酸酯乳液的合成、表征及其应用

以高交联性能的丙烯酸-4-羟基丁酯(4HBA)、丙烯酸丁酯(BA)、甲基丙烯酸十二氟庚酯(G04)等为聚合单体,通过延迟滴加氟单体的核壳乳液聚合工艺,合成了表面富含氟元素的含氟聚丙烯酸酯。采用红外光谱仪、热重分析仪、差示扫描量热仪、原子力显微镜、X光电子能谱仪及接触角测定仪表征了其性能与结构。分析结果表明:当G04质量为聚合单体总质量的20%时,聚合物干膜对水、油的接触角分别为94°和81°,表面能为31 J/m~2,交联单体4HBA的最佳用量为w(4HBA)=4%,该乳液在成膜过程中,氟元素优先向膜表面富集。     

Synthesis, microwave-assisted polymerization, and polymer properties of fluorinated 2-phenyl-2-oxazolines: a systematic study

We present a detailed systematic study of the synthesis and ability of fluorinated 2-phenyl-2-oxazolines to undergo polymerization. The synthesis of these compounds is based on a two-step procedure that gives the desired 2-oxazolines in moderate-to-good yields. All the compounds were fully characterized by IR and NMR ((1)H, (13)C, and (19)F) spectroscopy, mass spectrometry, and elemental analysis. The 2-oxazolines were subsequently used as monomers for living cationic ring-opening polymerization (CROP) with microwave irradiation as the heat source (T=140 degrees C), nitromethane as the solvent, and methyl tosylate as the initiator. The linear first-order kinetic plots of the polymerizations accompanied by a linear increase of the molecular weight with conversion and low polydispersity index (PDI) values (generally below 1.30) indicate a living polymerization mechanism. The resulting polymerization rates reflect a strong sensitivity to the quantity of fluorine substituents in general and the presence or absence of ortho-fluoro substituents of the phenyl ring in particular. All the polymers were isolated and characterized by size-exclusion chromatography and MALDI-TOF mass spectrometry. Finally, a detailed investigation of selected polymer properties was performed by using differential scanning calorimetry, thermogravimetric analysis, and contact-angle measurements, thus resulting in structure-property relationships. Whereas the thermal properties of the polymers are mostly influenced by the presence of ortho-fluoro substituents, the surface properties are mainly determined by the presence of para- and/or meta-fluoro substituents.