Evaluation of Setup Procedures on Mobile Devices Based on Users’ Initial Experience

Users’ initial perceptions of their competence are key motivational factors for further use. However, initial tasks on a mobile operating system (OS) require setup procedures, which are currently largely inconsistent, do not provide users with clear, visible and immediate feedback on their actions, and require significant adjustment time for first-time users. This paper reports on a study with ten users, carried out to better understand how both prior experience and initial interaction with two touchscreen mobile interfaces (Apple iOS and Google Android) affected setup task performance and motivation. The results show that the reactions to setup on mobile interfaces appear to be partially dependent on which device was experienced first. Initial experience with lower-complexity devices improves performance on higher-complexity devices, but not vice versa. Based on these results, the paper proposes six guidelines for designers to design more intuitive and motivating user interfaces (UI) for setup procedures. The preliminary results indicate that these guidelines can contribute to the design of more inclusive mobile platforms and further work to validate these findings is proposed.

黄土沟壑区砂石覆盖果园土壤剖面水分分布

以黄土高原沟壑区砂石覆盖苹果园为研究对象,对600 cm范围内土壤剖面水分含量的时间分异和空间分布状况进行了研究。结果表明:600 cm土层范围内,一周年内可划分为冬季增墒期和夏季失墒期两个阶段;土壤剖面水分空间分布随土壤深度的增加呈现波动性变化且稳定性不同,土壤含水量变化幅度随土层深度增加而变小,据此可将600 cm范围内的土壤剖面划分为速变层、相对稳定层、缓变层和稳定层;土壤水分在不同层次上的分布差异,8月土壤剖面不同层次含水量差异最大,11月次之,5月再次之,1月土壤不同层次含水量差异最小。综合看来,除土壤表层因砂石覆盖水分增加外,土壤剖面含水量随土壤深度的增加而减少且趋于稳定,水分下渗能力减弱;冬季土壤含水量多且分布均匀,夏季土壤水分减少且主要集中在上层,此时土壤不同层次水分含量差异大。

定植穴对局部土壤物理性质及苹果生长的影响

为了探索陕北黄土丘陵沟壑区苹果栽植成活率低、树体生长状况差的原因,对3种定植穴土壤物理性状及苹果生长状况进行了监测研究。结果表明定植沟、大定植穴降低了0～100cm土层土壤容重和开挖到雨季的土壤水分,其中开挖到定植是土壤水分散失的主要阶段。定植沟、大定植穴提高了0～100cm土层土壤总孔隙度、非毛管孔隙度和地面塌陷深度,相对提高了雨季期间的土壤水分,提高了枝条失水量和抽条指数,造成苗木成活率降低,树体生长量和产量降低。陕北丘陵沟壑区栽植苹果不宜采用雨季后开挖定植沟、大定植穴,翌年春季定植;春季定植时应以普通定植穴为主,并边挖边栽。

分光光度法同时测定无机多组份的研究

本论文由三部分工作组成。一、金属和岩矿中砷和锑连续测定方法的研究 本文基于新银盐测砷法和铁（Ⅲ）-邻菲啰啉测锑法，利用（月+弟）吸收液不吸收胂的特点，提出并建立了砷和锑连续测定的方法。文中研究并确定了砷、锑连测时的有关条件，较详细地考察了各种因素对砷测定结果的影响以及不同溶剂和某些金属离子（尤其是Ag~+和[AuCl_4]~-）对（月+弟）吸收率的影响。试验了胂、（月+弟）吸收显色液稳定性。探讨了铁（Ⅲ）－邻菲啰林与（月+弟）的氧化还原反应。研究了砷有色溶液的稀释条件和测定锑时的微量技术的应用，解决了砷含量明显高于锑的样品的分析问题。研究了砷和锑样品的高压、常压的消解方法，确定了样品消解的适应条件。研究了多种有机胺对胂、（月+弟）、（月+必）等吸收条件，找到了分离这些氢化物的有机胺的配比，消除了这些氢化物间的相互干扰，同时，研究了其他有关共存离子对砷、锑连测的影响及消除或减轻干扰程度的方法。方法的检出限为0.05ppmAs(3S)和0.09ppmSb(3S)。本方法具有仪器设备简单，操作简便快速，灵敏度高、精密度和准确度均较好等优点。通过对河流沉积物， 岩矿和金属样品的分析，证明本方法具有很好的实用价值。二、氢化物发生－分光光度法连续测定砷和铋的研究 本文探索了硝酸银吸收液吸收（月+必）的测定铋的方法，并在新银盐法测砷和铁（Ⅲ）－邻菲啰啉法测铋的基础上，利用砷（Ⅱ）和铋离子形成氢化物时受酸度的影响各不相同，提出了连续测定砷和铋的方法，对影响方法精密度和准确度的各种因素进行了实验，确定了适宜的分析条件。先从pH > 3的柠檬酸－氨水缓冲介质中，将铋离子还原成气态（月+必）吸收液吸收，尔后，提高反应液酸度至pH ≈ 1.0，再将砷（Ⅱ）从胂的形式还原出来，用胂吸收液吸收，于各自相应波长处测定各自吸收显色液的吸光度，分别计算砷和铋的含量。为了解决含量明显高于铋的样品的分析，我们采用稀释砷有色溶液的方法和用吸光度测量放大技术测铋，同时，采用定时高压法消解各种样品，获得较好的结果。文中还研究了共存离子对铋测定的影响，提出了消除干扰的方法。方法的检出限为0.07ppmAs(3S)和0.08ppmBi(3S)。本方法集分离、富集、显色于一过程内，具有简便快速，且灵敏度高、精密度和准确度均较好的特点，应用于河流沉积物、岩矿和金属样品中砷和铋的测定，得到满意的结果。三、分光光度法同时测定无机多组份的研究－CPA矩阵法同时测定锑、锡和锗 本文改进并研究了苯基萤光酮－op体系光度法测定锡、锗和锑的显色条件；研究了适宜于锑、锡、锗三元素同时测定的光吸收性质，根据ε值差异、吸光度加合性偏差和ε－bar的相对偏差来选择适宜的计算波长。采用Apple-CP60型微机处理数据，建立了CPA矩阵法同时测定锑、锡和锗的光度分析法。通过对合成样品的测定，证明了在CPA矩阵法中，由于引入非零截距和加入与试样相近的混合标准计算p矩阵，提高了方法的准确度，并扩大了方法的适用范围。文中还研究了锑、锡和锗与干扰离子的萃取分离条件。经简单的萃取分离干扰离子，将此法应用于河流沉积物的分析，获得满意的结果，成功地解决了性质相近元素锑、锡、锗的测定问题。

黄土高原沟壑区苹果园土壤重金属含量特征研究

以黄土高原沟壑区的苹果园为研究对象,对6~36 a苹果园土壤重金属含量状况进行研究,结果发现,该区苹果园的高投入种植管理模式,能够影响重金属在土壤中的迁移与富集,使土壤重金属含量发生明显变化。土壤Cu含量随树龄增加而增加,20 a以上的土壤-果树系统对土壤Cu的输入与输出趋于平衡,Cu含量变化不大,且耕层土壤Cu含量较高。Cr含量随树龄线性递增,36 a果园0~20 cm,20~40 cm和40~60 cm土层Cr含量分别比6 a果园增加27.14%,17.09%和19.17%。Cd含量随树龄增加先增加后减少,长期大量施用磷肥是土壤Cd的主要来源,果园生态系统深层土壤Cd含量的峰值比耕层提前出现。Pb含量以15~26 a果园含量最高,树龄<15 a和>26 a时Pb含量较低。Hg含量则以15 a为转折点,在不同土层上呈现出不同的变化趋势。As含量在树龄<15 a时逐渐降低,15~20 a时逐渐增加,20 a以后果园土壤As含量趋于不变,且各土层之间差异不显著。

黄土高原坡地苹果园土壤肥力及矿质氮累积分析

采用田间取样与室内分析相结合的方法,研究了黄土高原坡地苹果园肥力状况与矿质氮累积。结果表明,坡地苹果园土壤肥力低,氮、磷严重缺乏,钾相对丰富,土壤属于砂壤土,通气性强,保肥、保水性差。0—60cm土层土壤有机质含量为9.24～28.12g/kg,全氮为0.22～0.60g/kg,速效磷为0.17～16.08mg/kg,速效钾为80.06～168.39mg/kg;黄土高原坡地苹果园中NO3-—N有深层累积分布,累积深度大于2m,在180—200cm层最高累积量达249.61kg/hm2,而NH4+—N无深层累积。不同施肥处理对土壤剖面中的NH4+—N和NO3-—N含量分布影响不同,对NH4+—N含量和分布影响不明显,但不同施肥方式对NO3-—N含量分布影响显著。施加氮肥促进NO3-—N深层累积,施加磷肥有助于降低土层中的NO3-—N含量,缩小富集量的分布范围。

陕北丘陵沟壑区苹果优质丰产栽培体系研究

园址选择、优良品种搭配、坡地改良、合理施肥与抗旱栽培、合理修剪等是陕北丘陵沟壑区苹果优质丰产的保障 ,且同时论述了各项措施的操作依据和方法

黄土塬区果园套种对土壤微生物及酶活性的影响

研究了黄土塬区塬面不同套种作物的幼树苹果园土壤微生物的分布和酶活性。结果表明，果园土壤中微生物的分布在果树行与套种行中是不均匀的，细菌和真菌多为果树行多于套种行；土壤的过氧化氢酶，蔗糖酶，脲酶以及中性磷酸酶活性在套种小麦的果园中以套作行高于果树行，而套种烤烟则使脲酶和中性磷酸酶活性有所降低。套种豆类有利于土壤肥力的均衡发展。

黄土高原沟壑区沟坡地苹果优质丰产栽培技术体系

确立了黄土高原沟壑区沟坡地为优质苹果生产地带 ,建立起沟坡道路防蚀体系 ,春栽改秋栽 ,量化施肥、灌水、修剪 ,生态防治病虫害 ,加强优果生产和采后处理等是黄土高原沟壑区沟坡地带优质苹果生产的主要技术措施。

黄土区渭北旱塬苹果基地对区域水循环的影响

通过对苹果地、农田和其他塬面主要土地利用方式的比较研究 ,发现苹果地土壤入渗速率大、降雨产流率低和存在生物利用型土壤干层。这些水文学性质将增强土壤 -植物 -大气间垂直水分交换 ,削弱降雨转化为地表径流和地下水的比例 ,最终影响区域地表和地下水资源的数量。另外土壤干层的出现还削弱了土壤水库对年际和季节性干旱的调节作用 ,导致苹果产量随降雨量的自然变化呈现较大波动

微机控制的计时电流和计时库仑技术

设计和组装了用APPLEⅡ PLUS微型计算机控制的计时电流和计时库仑实验装置,用6502汇编语言和 BASIC 语言编制了实验控制、图形显示、图形描绘和数据处理程序,并用于测定薄膜修饰电极中电活性质点的扩散系数和研究电化学预处理玻炭电极表面的吸附行为。

The total margin of exposure of ethanol and acetaldehyde for heavy drinkers consuming cider or vodka

Heavy drinkers in Scotland may consume 1600 g ethanol per week. Due to its low price, cider may be preferred over other beverages. Anecdotal evidence has linked cider to specific health hazards beyond other alcoholic beverages. To examine this hypothesis, nine apple and pear cider samples were chemically analysed for constituents and contaminants. None of the products exceeded regulatory or toxicological thresholds, but the regular occurrence of acetaldehyde in cider was detected. To provide a quantitative risk assessment, two collectives of exclusive drinkers of cider and vodka were compared and the intake of acetaldehyde was estimated using probabilistic MonteeCarlo type analysis. The cider consumers were found to ingest more than 200-times the amount of acetaldehyde consumed by vodka consumers. The margins of exposure (MOE) of acetaldehyde were 224 for the cider and over 220,000 for vodka consumers. However, if the effects of ethanol were considered in a cumulative assessment of the combined MOE, the effect of acetaldehyde was minor and the combined MOE for both groups was 0.3. We suggest that alcohol policy priority should be given on reducing ethanol intake by measures such as minimum pricing, rather than to focus on acetaldehyde.

Gwaith Madog Dwygraig

Edwards, Huw, Gwaith Madog Dwygraig (Canolfan Uwchefrydiau Cymreig a Cheltaidd Prifysgol Cymru, 2007)

Characterisation and application of fruit by-products as novel ingredients in gluten-free products

The physicochemical and nutritional properties of two fruit by-products were initially studied. Apple pomace (AP) contained a high level of fibre and pectin. The isolated AP pectin had a high level of methylation which developed viscous pastes. Orange pomace also had high levels of fibre and pectin, and it was an abundant source of minerals such as potassium and magnesium. Due to the fibrous properties of orange pomace flour, proofing and water addition were studied in a bread formulation. When added at levels greater than 6%, the loaf volume decreased. An optimised formulation and proofing time was derived using the optimisation tool; these consisted of 5.5% orange pomace, 94.6% water inclusion and with 49 minutes proofing. These optimised parameters doubled the total dietary fibre content of the bread compared to the original control. Pasting results showed how orange pomace inclusions reduced the final viscosity of the batter, reducing the occurrence of starch gelatinisation. Rheological properties i.e. the storage modulus (G') and complex modulus (G*) increased in the orange pomace batter compared to the control batter. This demonstrates how the orange pomace as an ingredient improved the robustness of the formulation. Sensory panellists scored the orange pomace bread comparably to the control bread. Milled apple pomace was studied as a potential novel ingredient in an extruded snack. Parameters studied included apple pomace addition, die head temperature and screw speed. As screw speed increased the favourable extrudate characteristics such as radical expansion ratio, porosity and specific volume decreased. The inclusion of apple pomace had a negative effect on extrudate characteristics at levels greater than 8% addition. Including apple pomace reduced the hardness and increased the crispiness of the snack. The optimised and validated formulation and extrusion process contained the following parameters: 7.7% apple pomace, 150°C die head temperature and a screw speed of 69 rpm.