Measurement of Stone Diameter with Three Sizes of Automatically Fixating Stone Baskets

Background: Complications after endoscopic retrieval of kidney and ureter stones are obviously related to the size of the stones as well as the experience of the surgeon and other factors. During the procedure it is sometimes difficult for surgeons to estimate stone size and therefore give prognostic advises. The visual perception of the stone size depends on the shape, colour, distance to the renoscope and dilatation of the ureter. This is the so-called binding problem, because shape, color and direction of motion are processed separately by different population of optical neurons. In order to establish a better prognostic rational especially for less experienced surgeons, we established an intra operative semi-quantitative measurement of the stone size supported by a stone basket. Materials and Methods: We modified the tipped, nitinol stone baskets from the company Urotech with diameters of 2.5, 3.0 and 4 FR. The handle of this basket has a spring mechanism, which automatically closes the basket and provides a predefined fixation force of the stones within the basket. On the handle we established a non-linear scale in mm by grabbing standardized balls or standardized screws. Result: The scales are nonlinear because of the nonlinear relation between the diameter of the stone and the distance of the slider. Also the scales differ in between the basket size, because of the different strain conditions due to the different wire sizes and materials or the spring and basket. Conclusion: This scale could be an important orientation for a surgeon during endourological procedures to estimate stone sizes. After further clinical experience a semi-quantitative visualization like green, yellow and red colors could help to predict potential complications due to large stone sizes. Finally it could bevery interesting for other disciplines like gastroenterology.

Extracorporeal Shock Wave Lithotripsy Treatment for Renal and Ureteral Stones in Duhok City

The present study reports the results of extracorporeal shock-wave lithotripsy treatment for renal and ureteral stones in Duhok city. The data were collected from the center of breakdown kidney stones in Duhok hospital. There were a total of 40 patients (25 males and 15 females) aged from 20 to 60 years old. The patients harboring (23 renal and 17 ureteral) stones of size ranged from 7.5 to 20 mm. Almost stones are of average size 9 mm and composed of uric acid, calcium and cystine stones. The study has been carried out by taking into consideration the parameters (type, sizes, composition and location of stone as well as region and ages of patients, also power, number of shock wave and sessions). The results show that the stones size increases according to increasing ages of patients (male and female) for uric acid ureter stone and calcium (renal, ureter) stones. Also (renal, ureter) stone size for patients aged from 20 to 30 years old increases from the minimum value for phosphate to maximum value for cystine stones, while for patients aged from 40 to 60 years old, the minimum size is obtained for calcium oxalate and the maximum size for calcium only. On the other hand, for uric acid stones of average size 9 mm, number of shock wave and sessions as well as the power required to breakdown the stones decrease nearly exponentially according to enhancing patients’ ages. At the same time, it's found that for adult patients (20 - 30 years old), number of sessions and the power of shock wave decrease also according to increasing size of calcium and cystine stones. Contrary to that, for the same ages and renal, uretral cysteine stones number of shock wave needed to breakdown large stones will be increased.

Breakdown of Kidney and Ureteral Stones Using Extracorporeal Shock Wave Lithotripsy in Zakho City

In the present study, investigation of extracorporeal shock wave lithotripsy in Zakho City for breakdown kidney and ureteral stones has been carried out. The data were collected from the center of breakdown kidney stones in Zakho hospital. A total of 34 patients (25 male and 9 female) of ages ranged from 20 - 60 years were treated with ESWL. The patient harboring 24 renal stones and 10 ureteral stones of size ranged from 7 to 23 mm of almost patients are 8 mm and composed of calcium oxalate. The study has been conducted taking in to consideration the parameters (type, sizes, composition and location of stone as well as region and ages of patients, also power, number of shock wave and session). The results show that the number of shock wave decreases nearly exponentially with the ages of patients for calcium oxalate stone of size 8 mm under constant power 4 watt while it tends to increase according to increasing stones size for the patients of ages 20 - 30 years. The size of calcium oxalate stones decreases nearly exponentially with the patients’ ages for workers in Zakho city. Also for same size 8 mm of (calcium, phosphate, and oxalate) stones and different regions of zakho city, the number of shock waves decreases according to increasing ages of patients. Contrary to that for certain size of stones 8 mm, the number of shock wave starts to increase from uric acid to maximum value for calcium oxalate stone for the adult patients of age’s 22 up to 30 years. However for elders ages 30 - 60 years and different regions, the size of renal and ureteric stones increases from the minimum value for calcium, phosphate, oxalate to maximum value for calcium oxalate stone only. Uric acid stone requires minimum power to break, while the calcium oxalate needs maximum power to fragment due to its hardness composition. Later number of session of shock wave required for crushing each stones size increases according to increasing its size while its variation due to enhancing patients ages for calcium oxalate of size 8 mm results in nearly a decreasing exponential behavior.

Laboratory performance of stone matrix asphalt mixtures with two aggregate gradations

Stone matrix asphalt （SMA） is a gap-graded bituminous mixture which can be used in surface layer of high volume pavements. The mixture has higher concen- trations of coarse aggregates, providing strength and rut resistance to the mixture, and higher asphalt content giving durability. There must be a proper stone-to-stone contact between the coarse aggregates of SMA, and hence aggre- gate gradation is an important factor in this mixture. In the current study, two aggregate gradations, with nominal maximum aggregate sizes （NMAS） 16 and 13 mm were adopted to prepare SMA mixtures and their laboratory performances were compared. Polymer-modified bitumen （PMB） was used as the binder material and no stabilising additive was used, since drain down was within permissible limits for both mixtures with PMB. Conventional cylin- drical specimens were prepared in superpave gyratory compactor with bitumen contents 5.0 %, 5.5 %, 6.0 %, 6.5 % and 7.0 % by weight of aggregates, and volumetric and Marshall properties were determined. Tensile strength, behaviour to repeated loading etc. were checked for cylindrical specimens prepared at optimum bitumen con- tent, whereas specially prepared slab specimens were used to check the rutting resistance of SMA mixtures. From the laboratory study, it was observed that, out of the two SMA mixtures, the one with NMAS 16 mm performed better compared to the other. These improved properties may be attributed towards the larger coarse aggregate sizes in the mixture.

Characterization of some Egyptian serpentinites used as ornamental stones

Egypt is characterized by wide occurrence of serpentinites, particularly in the central and southern parts of Eastern Desert. There are several cooperate factors that affect the serpentinites used as ornamental stones. These factors involve mineralogical characteristics (including mineral composition and microstructure parameter), physical properties and mechanical properties. Antigorite is an essential serpentinite mineral, with a minor amount of chrysotile. Talc, carbonates (magnesite and dolomite) and tremolite are the main associated minerals. Quality and quantity of associated minerals such as talc and carbonates (dolomite and magnesite) affect the properties of serpentinites used as ornamental stones. Carbonates are resistant to weathering but suffer from acidic cleaning agents in interior use, whereas serpentinites with a high content of talc used on external faces undergo an increase in volume and a consequent rapid degradation. Studied serpentinites are characterized by relatively small grain size with foliated texture, low water absorption, low porosity, and high abrasion resistance. In the samples studied the uniaxial compressive strength (UCS) varies between 89 and 189 MPa, with an average of 152 MPa. According to the classification of Bell (1992), sample No. B8 is very high in strength while the rest high in strength.

不同石粉含量和粒径对砂浆干缩性能的影响

石灰石在开采和加工成机制山砂过程中产生了大量的废弃石灰石粉,石粉的堆放和去除会造成土地资源的浪费以及环境污染,为此,可将石粉加入砂浆中,以实现对石粉的合理应用。但是砂浆在加入石粉后会出现大量收缩,其耐久性大大降低。为了避免这种不利影响,将石粉等量取代水泥后的砂浆干燥收缩情况进行试验,研究了不同石粉含量和粒径对砂浆干燥收缩的影响。试验结果表明:在不同石粉粒径下,采用适量的石粉等量代替水泥可以有效减小混凝土的干燥收缩值,当石粉替代率大于15%时,砂浆干燥收缩值不断增大,石粉最佳替代率为10%;在不同石粉含量下,石粉粒径为800目和1250目下的砂浆干燥收缩值均较小,可作为工程实际中石粉外掺量的参考值。

大粒径级配碎石在旋转轴压下永久变形规律

为研究大粒径级配碎石在重复荷载作用下的永久变形规律,在道路材料旋转振动压实仪的基础上提出大粒径级配碎石混合料振动旋转压实室内研究制样方式,并采用旋转轴压重复荷载施加方式对成型试样施加重复荷载,最后引入AASHTO和Monismith模型对变形数据进行拟合。结果表明:当重复旋转轴压荷载等级低于200 kPa时,试样变形最终将趋于稳定,当荷载等级在240~320 kPa时,变形将缓慢累积且增速渐趋变缓,当荷载等级≥360 kPa时,变形将快速累积且增速保持在较高水平;AASHTO模型对低等级重复荷载作用下的累积变形拟合效果更好,Monismith模型对高等级重复荷载作用下的累积变形拟合效果更佳;旋转轴压荷载值、试样含水率和模型拟合参数的变化具有一定的关联。

浅谈陶瓷墨水对地铺石烧成后尺寸的影响

本文通过色料、釉料、坯料的成分分析,以及烧成机理研究,简单讨论了陶瓷墨水对地铺石烧后尺寸的影响。

弃石场碎石粒径与几何形状的识别与分析

以延崇高速桃韭梁弃石场为研究对象,对弃石场堆积的碎石进行识别与分析。通过数字图像处理技术,对获取的碎石影像资料进行图像识别、分析和处理,从获取的图像中统计其中碎石的粒径级配和几何形状,从而为后续建立弃石场边坡稳定性分析计算模型提供参考和依据。

国省干线养护工程大粒径级配碎石基层承载性能研究

通过现场承载力检测,研究了大粒径级配碎石基层承载性能。分析了重载交通量对大粒径级配碎石承载力形成机理及影响规律:承载力随重载交通作用次数分为明显增长阶段、增长缓慢阶段、无变化或降低阶段;研究了大粒径级配碎石承载力均质化提升机理:从全线整体弯沉情况分析,降低全线旧路弯沉离散程度,减缓旧路承载力的不均匀性。从局部变形进行研究,荷载作用区域,其顶面弯沉盆曲线斜率要小于旧路顶弯沉曲线斜率,加强路面变形协调性及对荷载传递扩散性,减缓应力集中现象;现场实测反算得到了大粒径级配碎石基层回弹模量约在700 MPa~850 MPa水平之间,较普通级配碎石模量回弹模量增长约在20%~320%,承载能力有较大幅度提升。

基于均衡性能的大粒径级配碎石基层施工关键技术

本文通过分析大粒径级配碎石施工及力学特点,研究基于性能均衡的大粒经级配碎石基层原材质量控制、施工级配优化、离析控制及处置关键技术。基于大粒级配碎石受力及施工特点,提出了大粒径级配碎石原材质量控制关键指标;确定了离析控制与嵌缝密实关键筛孔,并通过现场试铺验证了关键筛孔通过率,得到了大粒径级配碎石性能均衡施工级配控制范围;研究了大粒经级配碎石施工离析行为规律,针对不同施工环节离析行为特点,提出了大粒径级配碎石基层离析控制措施及离析病害处置关键技术。

基于DIC技术的大粒径水工沥青混凝土断裂性能研究

在水工沥青混凝土中断裂主要以张开型(I型)为主,为研究不同油石比下大粒径水工沥青混凝土的断裂性能,通过预裂缝小梁弯曲试验,并基于数字图像相关(DIC)技术对试件从加载到破坏过程中的水平应变进行分析。结果表明:在试验范围内不同油石比对大粒径水工沥青混凝土的断裂性能影响并不显著。不同油石比下沥青混凝土的临界应力强度因子和J积分断裂韧度变化均不明显,利用DIC技术可以较好地反映出试件在断裂过程中的应变情况,为沥青混凝土的断裂性能提供量化依据。

碎石尺寸对碎石土强度影响的大型直剪试验研究

以田师府—桓仁铁路大前石岭隧道边坡碎石土为研究对象,配置了3组含碎石尺寸不同的重塑碎石土样并采用大型直剪仪进行了剪切试验研究,探讨了碎石尺寸对碎石土抗剪强度的影响作用规律。在此基础上,利用现代非线性理论-分形理论,采用分形几何方法研究了该碎石土重塑样的粒度分布特征,得出了不同碎石尺寸下碎石土的分形维数,并探讨了碎石土的强度特征与粒度分形维数之间的关系。研究表明:在粗粒含量相同的情况下,碎石土的抗剪强度随着碎石尺寸的相对增大而增大;内摩擦角随着碎石尺寸的相对增大而增大;而黏聚力呈现相反的趋势,随着碎石尺寸的相对增大而降低;随着碎石尺寸的相对增大,分形维数增大,分形维数越大,其颗粒粒度分布越不均匀,反之分形维数越小,其颗粒粒度分布越均匀。碎石土抗剪强度和粒度分形维数有一定的相关性,黏聚力随着分形维数的增大而减小,而内摩擦角呈现相反的趋势,随着分形维数的增大而增大,黏聚力和内摩擦角均与粒度分形维数近似呈现抛物线函数关系。

土石混合介质饱和导水率的研究

采用恒定水头法对土石混合介质的饱和导水率进行测定，分析不同碎石含量及碎石直径对饱和导水率的影响，同时利用实测值对Peck—Watson及Bouwer—Rice两个传统估算方程的估测精度进行比较。结果表明：（1）饱和导水率随碎石含量先增大后减小，且两者呈二项式关系；（2）饱和导水率随碎石直径增大而减小，两者呈幂函数关系；（3）碎石直径介于1．0～5．0cm时，Bouwer—Rice和Peck—Watson方程对饱和导水率的估算结果均大于实测值。

低噪声沥青路面对缓解交通噪声的技术探讨

简要分析我国城市交通噪声的现状及趋势,重点从沥青路面材料、沥青路面构造深度和沥青混合料粒径大小三个方面来讨论低噪声沥青路面缓解交通噪声的原理和效果。

石煤钒矿粒度对酸浸提钒的影响

研究了石煤钒矿不同粒度矿物的性质及其对酸浸提钒的影响。结果表明,矿样中的CaO含量及浸出矿浆黏度均随粒度减小而逐渐增加;在+0.300-0.038 5mm的粒度区间内,随着粒度的减小,钒浸出率先增加后降低,在-0.074+0.045mm时浸出率最高,达93.04%,-0.045mm时,钒浸出率开始降低。在本试验条件下的适宜粒度区间为-0.300+0.045mm。

多种规格石料开采块度预测与爆破控制技术研究

针对多项工程要求的多种规格石料开采难题,以铁炉港采石场为工程背景,采用现场调研、工程试验、计算预测和爆破控制技术等方法,研究多种规格石的高效爆破开采技术。施工前,结合采场结构面调查结果和采场爆破漏斗试验,对采场进行岩体块度分区,绘制出满足工程开采的爆破块度分区图,提高了规格石开采的效率;借助Kuz-Ram数学模型,建立爆破设计参数与爆后石料不同块度所占百分率的关系式,根据此关系式可由爆破参数预测爆堆块度和爆破效果,并可根据预测结果对爆破参数进行优化;施工过程中,研究降低粉矿率的崩塌爆破技术,分析其作用机制,并通过对比耦合装药、全孔不耦合装药和不均匀不耦合装药结构的爆破效果,表明不均匀不耦合装药结构崩塌爆破技术能大大降低粉矿率和工程成本。现场应用情况表明,采用这一系列保证规格石开采的技术,不但能满足工程高质量的要求,而且经济效益显著。

石粉粉磨时间与其颗粒分布特性的相关性

选取大理石和白云石粉为材料,测试其不同粉磨时间的粒径分布,计算勃氏比表面积;粒径分布模型采用RosinRammler-Bennet(RRB)方程进行拟合,运用粉磨动力学和线性回归方法分析粉磨过程石粉的特征粒径、均匀性系数和比表面积。结果表明:随粉磨时间增加,粒径为0~10μm的颗粒逐渐增加,大于10μm的颗粒逐渐减少,两者粉磨效率随时间增加逐渐减小;相同时间时,大理石粉的高于白云石粉的;随时间增加,大理石粉均匀性系数增大,颗粒集中现象增多,白云石粉则相反;两者的比表面积和特征粒径与其粉磨时间呈对数和双对数相关。

尿液中的纳米微晶及其与尿石形成的关系

采用透射电子显微镜（TEM）、纳米粒度仪和X射线衍射（XRD）比较研究了正常人与尿石患者尿液中纳米微晶的形貌、尺寸及其分布，讨论了尿液中纳米微晶生长并聚集为大尺寸晶体的动力学模型。正常人尿液中纳米微晶的形貌较为圆钝，尺寸分布均匀，大都在100～300nm之间；而患者尿液中的纳米微晶棱角较为尖锐，尺寸分布不均匀，从几十纳米到1000nm不等，这导致其聚集倾向增加，形成尿石的几率增大。上述差异归因于正常人尿液中抑制剂的浓度及其活性比尿石患者的高，能抑制尿液中纳米微晶的生长和聚集。本实验结果表明，采用物理化学的方法减小尿液中纳米微晶的尺寸差异可能是防止尿石形成的措施之一。

钎焊金刚石砂轮磨削石材中金刚石粒度对磨削力的影响研究

本文通过测量不同金刚石粒度的高频感应钎焊金刚石砂轮磨削花岗石过程中的磨削力,对砂轮所受的法向力和切向力进行了研究。对不同粒度条件下磨削深度、进给速度和砂轮线速度对磨削力的影响进行了分析。研究发现磨削力随砂轮线速度的增大而减小,随磨削深度和进给速度的增大而增大,磨削深度对磨削力的影响程度比进给速度大。小粒度金刚石磨削时,磨削三要素对磨削力的影响比大粒度金刚石磨削时大。