词二首

水调歌头重上井冈山一九六五年五月久有凌云志,重上井冈山,千里来寻故地,旧貌变新颜。到处莺歌燕舞,更有潺潺流水,高路入云端。过了黄洋界,险处不须看。旅旗奋,是人寰。三十八年过去,弹指一挥间。可上九天揽月,可下五洋杯鳖,谈笑凯歌还。世上无难事,只要肯登攀。风雷动,念鸟儿问答奴娇一九六五年秋鱿鹏展翅,九万里,翻动扶摇羊角。背负青天朝下看,嘟是人问城郭。饱火连天,弹痕遍地,吓倒蓬间雀。怎么得了,哎呀我要飞跃。雀儿答道:有仙山晾阁。不见前年秋月朗,仃了三家条约。还有吃的,土豆烧熟了,再加牛肉。不须放屁,试看天地翻覆。借问君去何…     

十六字令 四首

新,传播新知建功勋。促四化,培育后来人。基,根深叶茂果如期。培沃土,百花满生机。通,杂交渗透贯纵横。百科间,万里架长虹。普,善把艰深化通俗。读者众,效益更突出。     

寓教于乐提高讲课艺术

教与学。教要得法,学要主动。主动来自兴趣,兴趣需要培养,培养在于乐教。教学中,善教者使学生如乘轻舟,扬帆顺风。学生待听课为“乐事”;不善教者使学生如入沼泽,举步艰难。学生视学习为“苦差”。同样教材,讲得生动,妙趣横生,回味无穷,学生百听不厌;讲得教条,枯燥乏味,学生呆如泥塑,事倍而功半。如何活跃课堂气氛,寓教于乐,提高讲课艺术。笔者就此谈谈自己的一些做法。     

《有机化学》1989年索引

产率23‘8%。m.p.91~93℃。C,。H,3NS,计算值:C,78.51;H,4.76;N,5.09;s,z一64、。实测值:C,78.76;H, 4.85;N,4.61;S,11.78。v二.二:3020,1590,1500,1470,1450,770,750,700 em一‘。乃,工:6.1了一7.46(m)Ppm。N一(2一毗咤蓦)吩嚷峰(3b) LO.Og Za,8.29 ld,80mL CoHoN02,7.09无水K:C03,1.09 Cu粉,反应12h,粗产物用硅胶柱层析分离。产率:29.7%。m.p一02~104℃。C17H::N:S,计算值:C,73.89;H,4.37;N,10.13;S,11.60。实测值:C,73.85;H,4,IB;N,9.96;S,1 2 .01。voa二:3050,3010,1600,1490,1470,1430,770,750,710 em一’。6H:6.76一8…     

微量元素的增龄变化

人体内有害元素含量随增龄而升高,而必需微量元素含量大多随增龄而降低。例如:美国的调查表明,老年人缺锌,发锰含量随年龄增长而下降,老年人下降特别明显。SANER发现,尿铬随增龄而减少。据上海测定,老年人发硒低于成年人。THIMAYAS等发现,青春期发硒明显高于老年期。人发硒含量一般于16~40岁开始下降,61~70岁年龄组最低。THOMSON等发现老年人血硒水平降低,关于铜的增龄变化,各测量结果很不一致。某些结果显示,血清铜的含量有随增龄而下降的趋势。据上海测定,老年人发铜明显升高。铁的增龄变化特点是,血清铁蛋白增多,铁贮量增多,骨髓利用铁下降。上海测定结果显示,老年人发铁比年轻人明显升高。微量元素的增龄变化@颜世铭     

我们是怎样进行复习展览的

通过通报的介绍,与友校的经验,我们于大前年举行了一次复习展览。以后每学期按期举行,并在平日选定一些专题作展览,陈列在图书馆的阅览室,与实验室门前通路上。如酸,硷,盐性质比较,金属非金属标本,煤,石油等专题。在摸索过程中,首先是贪多,选好看的,整套的多排,以致内容分散。以后又过于简略。首先是安排实验,再考虑给予思考题。后来是整理综合成为几个项目,分别拟具思考题,再研究陈列些什么东西。每次进行筹备计划性逐渐加强,考虑的问题也比较集中。(1)准备复习展览的陈列,应在钻研教材的基础上,明确重点,选择主要教材,和能说明本质的实验装置和直观教具。只有掌握化学教材的理论体系,才能给予同学生系统的巩固的科学知识。从卤素到硫氮碳     

中国古代造酒的化学工艺

酒是人类知道火食以后,最早制造的嗜好品饮料。所以,未开化的国家。也往往有酒。但酒的制法,各国各地不同。古今的酒的制法和气味,也不能一致。我国的酒,依史籍上考证,孟子说:“禹恶旨酒”。战国策是战国时人著的,它也记载说:“仪狄(人名)作酒,禹饮而甘之。曰,后世必有以酒亡其国者。遂疏仪狄而绝旨酒”。可见,夏禹时候已有了酒。而旨酒是美酒,仪狄做的特别美。禹怕给他做的美酒耽误事,所以不愿喝他的酒,和他疏远了。想在仪狄以前,也许早有做酒的,不过史书上没有记载。有人因黄帝素问和神农本草经已载了     

学龄前视力低常儿童散光眼分布特征分析

目的分析学龄前视力低常儿童散光眼分布特征,全面探究其散光类型、分布以及矫正情况,旨意为相关研究人员提供理论依据。方法选择2016年1月至2016年12月温州医科大学附属眼视光医院收治的912例学龄前视力低常者(1 730眼)为研究对象,实施散瞳验光,分析统计学结果。结果单眼散光者94例,占10.3%。双眼散光者818例,占89.7%。对称性散光者710例,占86.6%,不对称散光者108例,占13.2%。顺规散光1 646眼,占95.1%,逆规散光64眼,占3.7%,斜轴散光20眼,占1.2%。矫正视力在0.9以上者共计412眼,占23.8%。0.8以下共计1 318眼,占76.2%。在该部分群体中,远视性散光共计1 042眼,近视散光共计30眼。混合散光共计246眼。复性远视散光1188眼,占68.7%,复性近视散光38眼,占2.2%。单纯近视散光6眼,占0.4%,单纯远视散光204眼,占11.79%。混合散光294眼,占17.0%。0.50 D~1.00 D占31.7%,1.25 D~2.00 D占46.4%,2.25 D~3.00 D占15.6%,3.25 D~4.00 D占4.9%,4.25 D~5.00 D占1.3%。5.25 D以上占0.2%。结论在学龄前视力低常群体中,双眼散光为常见疾病类型,其中以复性远视散光为主。散光程度一般在3.00 D以下,轴向分布以顺规散光为主。重度散光为引发弱视的主要因素,因此对于视力低常学龄前儿童,应当做好早期视力筛查,以便尽早矫正散光,恢复正常视力。     

北京市第四中学简介

北京四中的前身是顺天府中学堂,成立于1907年。建校以来,培养了许多优秀学生,受到广泛赞誉。我校历来认真贯彻党的教育方针,发扬好传统,科学育人才。现有25个教学班,1100名学生,教职员工200余人。师生之间,教学相长,亲切和谐,一派生气。     

中国外丹黄白术史略

一、释金丹黄白外丹东晋葛洪抱朴子有金丹篇,但未释金丹之义。国符以为:丹即丹砂,即红色之硫化汞。金丹者,丹砂而可制黄金(药金)者,如黄帝九鼎神丹等金丹,皆可制黄金(药金)。金丹作法,须用飞炼。所谓飞者,即简单之升华;或数物加热至高温,同时所得产物,即行升华也。此种黄金,为黄色物,自汉至晋认为与真黄金相同。至唐初,称此种黄金为药金,并知识别药金与真黄金之法,黄白者:汉书艺文志著录泰壹杂子黄冶三十一卷。晋灼曰:黄冶,铸黄金也,道家言冶丹砂变化可铸作黄金也。抱朴子黄白篇曰:“黄者,金也。白者,银也。古人秘重其道,不欲指斥,故隐之云尔。或题篇云庚辛,庚辛亦金也”。最初金     

微机控制动态配气装置的研究

按照ISO6145标准，设计，研制了微机控制动态配气装置，实现了微机对动态配气装置主要动态参数的实时监控，存储和结果处理，将该动态配气装置与静态容量法配气装置进行了比较，两种方法配制的标准气体的量值一致，对动态法配气的量值不确定度进行了评定。     

离子色谱测定烟草中果胶方法的改进

为了提高YC/T 346–2010果胶含量测定方法的分析速度,将标准中醇化除糖、滤渣酸化两步前处理优化为一步,即酸醇溶液加热回流同时除糖和酸化,并将方法改进前后的测定结果进行比较分析。一步前处理方法线性相关系数为0.999 9,回收率为93.57%~102.29%,测定结果的相对标准偏差为4.92%(n=5)。该方法简化和缩短了样品前处理步骤和时间,测定结果与YC/T 346–2010一致,可用于烟草中果胶含量的批量测定。     

Determination of creatinine in serum by high-performance liquid chromatography: a comparison of three ion-exchange methods

Three ion-exchange high-performance liquid chromatographic methods for the determination of creatinine in serum have been compared. In method 1 a strong cation exchanger was used. In method 2 a reversed-phase column was given strong cation-exchange properties by the addition of N-methyloleoyl taurate to the mobile phase. In method 3 a weak cation exchanger was used. Elution was with a pH gradient in methods 1 and 2, and isocratic elution was used in method 3. The imprecision was similar for the three methods and varied between 0.9 and 2.5% as studied within-day and between 1.4 and 3.2% from day-to-day. The lowest coefficient of variation was obtained around the upper reference limit. Analytical recoveries were quantitative for the three methods. The method with N-methyloleoyl taurate showed no advantages over the conventional strong cation exchanger. With the weak cation exchanger no interferences were detected from compounds investigated, but with the strong cation exchanger a slight interference was obtained with uric acid. We prefer the weak cation-exchange method because of its simplicity, higher throughput and absence of interference from hitherto tested compounds.     

比对法在计量标准考核验证中的应用探讨

为探讨比对法在计量标准考核验证中的可行性,将5家实验室分别对同一分度吸量管的检定结果进行比对,同时采用具有溯源性的传递比较法进一步验证比对法的可靠性。验证结果显示,采用比对法和传递比较法对被考核实验室的验证结果一致,说明采用比对法对检定结果的验证是有效的、可行的。     

Liquid chromatographic determination of pyrantel tartrate in medicated formulations

The validation of a novel liquid chromatographic (LC) method for the determination of pyrantel tartrate in feed is presented. The method provides a significant improvement over the efficiency and precision of AOAC Official Method 978.30. The method was shown to be accurate, precise, linear, and robust for medicated articles. Unlike the official method, the LC method was shown to be a superior stability-indicating method. After the method was validated by using laboratory blends, the effectiveness of the method was demonstrated with marketed product as well.     

Dynamic ultrasound-assisted extraction coupled on-line with solid support derivatization and high-performance liquid chromatography for the determination of formaldehyde in textiles

An on-line method was developed for the extraction, derivatization and determination of formaldehyde in textile samples. Formaldehyde was first extracted with water by ultrasound assisted, and directly introduced into a derivatization column which was packed with a moderately sulfonated cation-exchange resin. The resin used as solid support for the derivatization was charged with 2,4-dinitrophenylhydrazine (DNPH) previously. The formaldehyde DNPH derivative was eluted with the chromatographic mobile phase into an analytical column for the separation, and then monitored by UV detector. The maximum extraction yield was achieved when the extraction vessel was located at 10mm from the ultrasonic source and 10mg textile sample was extracted with 5mL pure water at a flow rate of 1.0mLmin(-1) at 50 degrees C. The detection limit of the proposed method was 0.06mgkg(-1). This method was applied to the determination of formaldehyde in different textile samples, and compared with the state standard method (off-line spectrophotometry) used in China. The similar contents of formaldehyde were obtained for most samples by the two methods, but little higher for some samples obtained by the proposed method. The average relative standard deviation (RSD) obtained by the on-line method was 3.2% which is lower than 29.5% obtained by the standard method.     

Effect of gas supply method on the performance of the single-chamber SOFC micro-stack and the single cells

The effect of gas supply method on the performance of a single-chamber solid oxide fuel cell micro-stack and single cells was studied, and a novel gas supply method with separated gas vents in the gas tube was proposed. The traditional gas supply method was also investigated for comparison. Results showed that the single cells could obtain a uniform open-circuit voltage and power output by using the separated gas supply method. For the traditional gas supply method, the cell at the outlet position yielded inferior performance compared to that of the inlet cell. The gas flow rate showed a significant effect on the performance of the cells. Finally, the stack operated with the separated gas supply method produced a higher power output than that operated with the traditional gas supply method.     

Development of a new analytical method for the determination of red beetroot betalains using dispersive solid‐phase extraction

The objective of this study was to develop a method for the determination of red beetroot betalains based on the dispersive solid‐phase extraction and modified QuEChERS methods followed by micro‐high performance liquid chromatography coupled with a mass spectrometer that was equipped with a quadrupole and time‐of‐flight detector. Currently, new techniques for the extraction of the pigments are necessary and in this study, an extraction of beetroot betalains based on the QuEChERS method was developed for the first time. Twelve variants of the methods with different sorbent combinations were tested. The extraction with 15% methanol and with 0.05% formic acid was performed as a reference method to compare the obtained results. In all of the samples with the addition of sorbents, a lower noise was demonstrated in the obtained results. The betalain concentrations obtained using the tested methods were 0.32–0.54 mg g^?1, while the value of the reference method was 0.44 mg g^?1. The method that used the strong ion exchange sorbent (0.44±0.05 mg g^?1) was the most adequate in terms of analyzed content, related standard deviation value and interference compared to the reference method. It was concluded that the properly modified QuEChERS method can be successfully applied for the determination of red beetroot betalains.     

Atomic absorption inhibition titration of orthophosphate and polyphosphates

The atomic absorption inhibition titration of phosphates was studied for two types of burner. Dependence on gas Flow-rates was observed. The method with a pre-mix burner was employed to determine phosphate in surface and waste waters. The results are compared with those by the standard method. The proposed method was found to be rapid, simple and accurate.     

Performance of a proposed determinative method for p-TSA in rainbow trout fillet tissue and bridging the proposed method with a method for total chloramine-T residues in rainbow trout fillet tissue

Chloramine-T is an effective drug for controlling fish mortality caused by bacterial gill disease. As part of the data required for approval of chloramine-T use in aquaculture, depletion of the chloramine-T marker residue (para-toluenesulfonamide; p-TSA) from edible fillet tissue of fish must be characterized. Declaration of p-TSA as the marker residue for chloramine-T in rainbow trout was based on total residue depletion studies using a method that used time consuming and cumbersome techniques. A simple and robust method recently developed is being proposed as a determinative method for p-TSA in fish fillet tissue. The proposed determinative method was evaluated by comparing accuracy and precision data with U.S. Food and Drug Administration criteria and by bridging the method to the former method for chloramine-T residues. The method accuracy and precision fulfilled the criteria for determinative methods; accuracy was 92.6, 93.4, and 94.6% with samples fortified at 0.5X, 1X, and 2X the expected 1000 ng/g tolerance limit for p-TSA, respectively. Method precision with tissue containing incurred p-TSA at a nominal concentration of 1000 ng/g ranged from 0.80 to 8.4%. The proposed determinative method was successfully bridged with the former method. The concentrations of p-TSA developed with the proposed method were not statistically different at p < 0.05 from p-TSA concentrations developed with the former method.