具有南海海洋资源特色的海洋药物化学成分预实验设计探索

选择以海南特色的海洋药用植物及动物为实验药材,如南海红树林植物、海星等作为《海洋药物化学》化学成分预实验中的实验对象,开展糖、甾体、生物碱、酚酸、黄酮等海洋天然产物的鉴别分析,使《海洋药物化学》实验课程的设置具有鲜明的南海海洋资源特色,为海洋药学专业课程设置,提供很好的南海特色,为海洋药学专业人才培养提供参考。

烟草化学成分分析实验课融入“课程思政”的教学探索与实践

课程思政建设是实现“三全育人”的重要手段。烟草化学成分分析实验是烟草专业的核心专业实践课程。为了切实发挥好课程育人功能,实现学思结合、知行统一的培养目标,文章分析了现行模式下烟草化学成分分析实验课程思政教学存在的问题,并从课程思政设计、教学内容、教学模式和考核评价等方面进行了改革探索,从而为相关专业课程思政教育改革提供参考和借鉴。

沙戟的显微鉴别与化学成分预实验

目的对沙戟的显微结构和化学成分进行初步探索。方法采用徒手切片技术、水合氯醛透化法对沙戟的茎和叶的解剖特征以及组织粉末的特征进行研究;采用系统预实验法对沙戟中可能含有的化学成分进行预实验检识,初步探索沙戟中的化学成分。结果沙戟的茎和叶的解剖结构特征与粉末特征较为显著,可见无限外韧型维管束、木栓组织、平轴式气孔、不定式气孔、非腺毛及螺纹导管等。沙戟的水提液、乙醇提取液、石油醚提取液中可能含有糖类、鞣质、有机酸、黄酮类、香豆素、生物碱、三萜类等化学成分。结论沙戟的茎和叶的解剖特征以及粉末特征可为沙戟的生药鉴定提供解剖学依据,沙戟化学成分预实验检识结果可以初步确定沙戟中含有多种有效成分,能为沙戟的进一步开发利用提供基础。

磁场对液体燃料成分的影响

文章给出了75#汽车，1#航空煤油，0#柴油，95%工业酒精在磁场作用下成份变化的实验结果，探讨了磁场对燃料分子和分子团的作用机理，阐述了磁化燃料提高燃烧效率和减少冒烟的原因。

白芨及其替代品化学成分预试及薄层色谱分析

白芨为常用中药,市场上有不少替代品。为评价其代用价值,采用植物化学成分系统预试法、紫外分光光度法、DNS法、蒽酮比色法分别测定了白芨及其代用品的主要化学成分、总黄酮、还原糖和总糖含量。结果表明:白芨及其代用品所含成分相似,均含有氨基酸、糖类、甙类、鞣制、有机酸、生物碱、皂苷、黄酮类、酚类、内酯、香豆素及其苷类、强心苷、甾萜类等物质,其中以多糖和黄酮反应比较明显。筒瓣兰的黄酮含量最高为0.35%,其次为白芨0.20%,苞舌兰为0.10%;白芨的总糖含量最高为66.11%,依次为筒瓣兰58.41%和苞舌兰42.67%;还原糖的含量白芨2.91%,筒瓣兰为2.25%,苞舌兰2.34%。在365nm波长处苞舌兰与筒瓣兰有3个(Rf值为0.32,0.51,40.56)和2个荧光点(Rf值为0.51和0.57)与白芨一致,说明筒瓣兰、苞舌兰与中药白芨成分相似,具有一定的替代价值。

“人体废物的排出”教学中实验的挖掘与设计

＂人体废物的排出＂是苏教版初中生物学七年级下册第十一章第二节的内容。对于人体的废物———尿液,学生既陌生又熟悉。熟悉在于人每天都会排尿,且尿臭、尿脏;陌生在于学生并不清楚尿液里究竟有什么物质。而教材对于尿液的组成成分仅以阅读资料和解读数据的形式呈现,重在分析,缺乏感性。为了让学生能进一步接触尿液、认识尿液,获得正确的情感、态度观,笔者设计了以下实验。

Physicochemical Characterization of Surface Water of the Area of Gafsa

Water exploits an essential part in all the durable development, the exploitation of this natural resource, its management and its position, its mineralization, its underground course and the mode o fits resurgence. The area of Gafsa is known by its very important hydrous potential which is geographically in the zone of transition between central Tunisia and the Saharan platform, these two great fields are separated by the fault of Gafsa which plays an important part in the structuring of the basins of the area, the hydrous resources of Gafsa make subsoil water the principal source of supply water, in the absence of an important network of surface. The zones of studies present requirements out of water which do not cease growing with the progress of the industrial activities and the concentration of the agricultural activities： The objective of this work is to analyze the water of the various zones of the area of Gafsa and to treat it to make it possible most drinkable. The analyzes like measurement of pH, measurement of electric conductivity and measurement of dry residue were made in the laboratory of the chemical group of Mdhila in Tunisia and in laboratory of Ion exchanger Materials of Vitry in France, the processes of treatment as opposite osmosis are also programmed in this same laboratory. The results are very encouraging to start the study and the design of a station of potabilisation of water in the area of Gafsa.

Resistivity in Formation and Decomposition of Natural Gas Hydrate in Porous Medium

A new one-dimensional system for resistivity measurement for natural gas hydrate(NGH)exploitation is designed,which is used to study the formation and decomposition processes of NGH.The experimental results verify the feasibility of the measurement method,especially in monitoring the nucleation and growth of the NGH. Isovolumetric formation experiment of NGH is performed at 2°C and 7.8 MPa.Before the NGH formation,the initial resistivity is measured to be 4-7Ω·m,which declines to the minimum value of 2-3Ω·m when NGH begins to nucleate after the pressure is reduced to 3.3 MPa.As the NGH grows,the resistivity increases to a great extent,and finally it keeps at 11-13Ω·m,indicating the completion of the formation process.The NGH decomposition experiment is then performed.When the outlet pressure decreases,NGH begins to decompose,accordingly,the resistivity declines gradually,and is at 5-9Ω·m when the decomposition process ends,which is slightly higher than the resistivity value before the formation of NGH.The occurrence and distribution uniformity of NGH are determined by the distribution and magnitude of the resistivity measured on an one-dimensional sand-packed model.This study tackles the accurate estimation for the distribution of NGH in porous medium,and provides an experimental basis for further study on NGH exploitation in the future.

Experimental measurement and numerical analysis of fused taper shape for optical fiber coupler

To find out the effect of the shape of fused taper region on the optical fiber coupler, the fiber couplers were fabricated at different drawing speeds with a six-axes fiber coupler machine. The results, which were obtained fi＇om the shape of fused taper region measured with microscope, show that there is a close correlation between the cone angle and optical performance of fiber coupler. High-performance fiber coupler cannot be obtained until rheological shape is controlled accurately. The numerical analysis model, which was built based on generalized Maxwell viscoelastic theory, is resolved with ANSYS software. The calculated results accord with the experimental data. It can apply a theoretic basis for forecasting the shape of fiber coupler fabricated under the conditions of different technological parameters.

Effect of Modified Atmosphere Packaging on Postharvest Quality of Barangan Banana

An experiment retail film packaging system was used to compare the atmospheric composition within sealed packs containing barangan banana fruits. This research was done in order to study the effect of packaging films with different permeability properties on the physicochemicalproperties of barangan banana during storage at room temperature （28 ± 2 °C） and at 15 °C. The films used were 0.09 mm low density polyethylene （LDPE）, 0.04 mm polypropylene and 0.057 mm LDPE compared with unwrapped fruits as control. Barangan bananas were evaluated each 5 days intervals for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped barangan bananas were overripe and soft after 15 days at both temperature conditions. Sealed packages especially using LDPE at 15 °C delayed the development of the yellow color of banana until 20 days of storage and had the lowest weight loss.

Effects of modified clay flocculation on major nutrients and diatom aggregation during Skeletonema costatum blooms in the laboratory

Harmful algal blooms(HABs) can elicit several negative effects on aquatic environment(such as depleting the oxygen, blocking the sunlight, destroying the habitats of organisms) and life health(including poisoning/killing marine mammals, birds and human). Among the various control strategies for HABs(physical manipulation needs lots of manpower and expensive equipment, chemicals treatment has some toxic byproduct and high residual, microbial agents only has limited in laboratory research), the coagulation-flocculation of HAB species by modified clay(MC) has been proven to be an effective, lowcost and environmentally friendly method that has been widely applied in the field, particularly in eastern Asia. In order to examine the long-term effects of MC treatment, this study investigated the alternations in seawater of Skeletonema costatum, a high biomass dominant HAB species along the Chinese coast, by comparing the degradation of S. costatum detritus(A1) with the application of MC treatment(A2) and MC treatment in sediment condition(A3). The low dosage of 0.25 g/L MC could efficiently remove 4×108 cells/L of S. costatum cells within 3.5 h(approximately 97% removal). In addition, the results showed that both inorganic and organic nutrients were effectively reduced from seawater by MC particles. Compared to the total nitrogen(TN) and total phosphorus(TP) concentrations in A1 seawater, 44% of TN and 93% of TP in A2 seawater, as well as 72% of TN and 93% of TP in A3 seawater were removed during the onemonth incubation period. Simultaneously, 64% of DISi in A2 and 44% of DISi in A3 significantly decreased( P <0.001). This study demonstrated that MC treatment was able to significantly increase the downward flux of nutrients and delay the release velocity of inorganic nutrient from MC-algae matrix into the overlying seawater, particularly within sediment environment.

Study on the network delay of periodic information in the NCS based on EPA

The network delay of the periodic messages transmission in the network control system （NCS） based on Ethemet for plant automation （EPA） is analyzed from the theoretical and experimental perspective in this paper. The composition and the characteristics of the network delay of EPA periodic messages transmission in a subnet is studied through analyzing the information transmission regularity and EPA deterministic scheduling mechanism. On this basis, the queuing delay at communication schedule management entity （EPA _ CSME） that is the most important component of network delay is analyzed, during which the formulas for the queuing delay of periodic messages and other real time parameters are proposed. Furthermore, an experiment is developed to test each component of network delay of periodic messages transmission in a EPA subnet. According to the experimental and the theoretical analysis, the conclusion is drawn that the delay during which the periodic messages wait for the periodic messages transmission time slice is the main factor that causes considerable network delay, and improvement method is presented.

Influence of medium components on elastase production using crude sources by Bacillus sp.EL31410

A newly isolated strain EL31410, producing elastase (E.C3.4.4.7) with h igh elastolytic activity was identified as Bacillus sp. In the medium opt imizat ion, it was found that wheat bran and soybean flour hydrosate were the best crud e carbon and nitrogen source for enzyme production, respectively. Addition of co rn steep flour can affect the bacterium growth and elastase production. A fracti onal factorial design was applied to study the main factors that affect the enzy me production, and central composite experimental design and response surface me thodology were adopted to derive a statistical model for the effect of wheat bra n and soybean flour hydrosate on elastase production. The experimental results s howed that wheat bran had positive effect but soybean flour hydrosate had neg ative effect, on enzyme production. An initial concentration of 3.4%(w/v) wh eat b ran and 9.4%(v/v) soybean flour hydrosate were found to be optimal for enzyme pr oduction in batch culture. The time course of elastase production in the optimiz ed medium composition was also described.

Corner forming of AZ61A magnesium alloy tube within warm hydroforming

The comers with small radii on cross sections are crucial for forming hydroformed components with polygonal sections. In this paper, warm hydroforming experiments of AZ61A magnesium alloy tubes were cartied out to study the forming regularity of round comers by using a demonstration part with square sections. Effects of temperature on radius forming, thinning ratio distribution and microstructure were revealed and a component with relative outer corner radius of 3.0 was obtained by warm hydroforming at 240℃. The minimum thickness of the formed square section was located in the transition position between the corner and the straight wall. The thinning ratio of the round corner increased with the increase of forming temperature. Fotmability of the magnesium tube was improved by raising temperature under the effect of dynamic recrystallization at 240℃.

Study on Aroma Components of Six Kinds of Plum Fruits

[Objective] The aim was to study the aromas composition of plum fruit. [Method] The aroma components of six kinds of plum fruits were analyzed by SPME, detected and identified by GC-MS.[Result] 85 kinds of aroma substances were separated and identified, including 40 kinds of common components.The experiments had good reproducibility by strictly controlling the desorption temperature, time and sample holding time.The obtained chromatographic peak retention time and the normalized area variation coefficient CV% values were between 0.03% -0.54% and 5.85% -18.08% by experimenting the five precision of AoLi13.The qualitative and quantitative were fully meet repeatability requirements for test samples. [Conclusion] The study provided scientific basis for the development and process of plum industry in China.

Study of full waveform inversion based on L-BFGS algorithm

Full waveform inversion size of full waveform inversion will and the limitation of full waveform is mainly used to obtain high resolution velocity models of subsurface. The lead to a gigantic computation cost. Under the available computer resource inversion, the authors propose L-BFGS algorithm as the optimization method to solve this problem. In order to demonstrate the flexibility of the method, three different numerical experi- ments have been done to analyze the properties of full waveform inversion based on L-BFGS.

Experimental investigation of friction coefficient in tube hydroforming

The friction coefficient between tube and die in guide zone of tube hydroforming was obtained. In hydroforming, the tube is expanded by an internal pressure against the tool wall. By pushing the tube through tool, a friction force at the contact surface between the tube and the tool occurs. In guiding zone, the friction coefficients between tube and die can be estimated from the measured axial feeding forces. In expansion zone, the friction coefficients between tube and die can be evaluated from the measured geometries of expanded tubes and FE analysis.

Experimental study on co-pyrolysis characteristics of typical medical waste compositions

Thermal decomposition of 21 kinds of binary mixtures between typical medical compositions was investigated under nitrogen conditions by dynamic thermogravimetric analysis(TGA) at 25–800 °C. The weighed sum method(WSM) coupled with thermal analysis was applied to study the interaction between components. Then, co-pyrolysis kinetic model of the binary mixtures(tube for transfusion(TFT) and gauze) was established to verify the reliability of conclusions. The results show the follows. 1) Strong or weak interactions are shown between binary mixtures containing polyvinyl chloride(PVC), the main ingredient of TFT. The addition of other medical waste could enhance first stage decomposition of TFT. While, the secondary stage pyrolysis may be suppressed or enhanced or not affected by the addition. 2) There exists no interaction between catheter and other component, the DTG peak temperature representing Ca CO3 decomposition in catheter fraction is obviously lower than that of pure catheter; while,the shape of DTG peak keeps unchanged. 3) No evident reaction occurs between the other mix-samples, it is considered that their co-pyrolysis characteristics are linear superposition of mono-component pyrolysis characteristics.

An Experimental Deprivation Study of Mobile Phones, Internet and TV

This paper presents the results of an experimental deprivation study conducted with 64 participants. All participants had to do without mobile phone, internet and TV for 15 days each. The main research objective was to examine the differences of indispensability levels and experiences during these non-usage phases. Mobile phones turned out to be most indispensable followed by Internet. Involvement of the medium into daily routine is an important part of short-term indispensability and will be dealt with in detail in this paper.

Clipping Alters the Response of Biomass Production to Experimental Warming: A Case Study in an Alpine Meadow on the Tibetan Plateau, China

Predicting how human activity will influence the response of alpine grasslands to future warming has many uncertainties.In this study, a field experiment with controlled warming and clipping was conducted in an alpine meadow at three elevations（4313 m, 4513 m and 4693 m） in Northern Tibet to test the hypothesis that clipping would alter warming effect on biomass production.Open top chambers（OTCs） were used to increase temperature since July,2008 and the OTCs increased air temperature by approximately 0.9o C ~ 1.8o C during the growing in2012.Clipping was conducted three times one year during growing season and the aboveground parts of all live plants were clipped to approximately 0.01 m in height using scissors since 2009.Gross primary production（GPP） was calculated from the Moderate-Resolution Imaging Spectroradiometer GPP algorithm and aboveground plant production was estimated using the surface-measured normalized difference vegetation index in 2012.Warming decreased the GPP, aboveground biomass（AGB） and aboveground net primary production（ANPP） at all three elevations when clipping was not applied.In contrast, warming increased AGB at all three elevations, GPP at the two lower elevations and ANPP at the two higher elevations when clipping was applied.These findings show that clipping reduced the negative effect of warming on GPP, AGB and ANPP, suggesting that clipping may reduce the effect of climate warming on GPP, AGB and ANPP in alpine meadows on the Tibetan Plateau, and therefore, may be a viable strategy for mitigating the effects of climate change on grazing and animal husbandry on the Tibetan Plateau.