MODELING of LOOP REACTOR FOR POLYPROPYLENE SPHERIPOL TECHNOLOGY

在ASPEn POlyMErS PluS软件平台上模拟SPHErIPOl聚丙烯工艺中核心液相环管反应器,采用了等效的全混流反应器模型和组合式环管反应器模型,结合工厂现场采集的数据,拟合了丙烯聚合反应动力学模型,并将该模型用于2种环管反应器模拟方法的比较。采用组合式环管反应器模型考察了丙烯聚合反应循环比对反应器撤热、聚丙烯产量和相对分子质量分布、反应器内氢气浓度分布的影响。结果表明,在高循环比操作条件下和误差允许范围内,环管反应器可以等效为一个全混流反应器。当控制环管反应器夹套冷却水出口温度不变时,过低的循环比使得反应器内的温度分布不均匀,而过高的循环比则使环管反应器的撤热能力下降;当循环比增加时,环管反应器内的温度和组分浓度梯度减小,停留时间分布均匀,趋于全混流状态,催化剂活性得到充分发挥,聚丙烯产量也相应增加。Both the continuous stirred tank reactor model and the combined tubular loop reactor model were set up to simulate the steady-state performance of the industrial tubular loop reactor of Spheripol technology of propylene polymerization based on the Aspen Polymers Plus software.A comprehensive catalyzed polymerization kinetic model was verified by using plant data,and was employed to analyze the operational performance of the two models.It was observed that in high recycle ratio for propylene polymerization,the tubular loop reactor could be simulated,to a certain error degree,by a continuous stirred reactor.In addition,the effects of recycle ratio on the performance of the loop reactor could also be obtained via the combined model.The simulated results showed that the low recycle ratio made the temperature change along the tubular loop reactor in a large range under the constant coolant outlet temperature,while the high recycle ratio made the reaction temperature uniform in the tubular loop reactor,but the capacity of heat evacuation reduced.On the other hand,with the increase of recycle ratio,the concentration gradients of reaction components were lowered,and the polypropylene production was enlarged,approaching to the performance of the continuous stirred reactor.中国石油天然气股份有限公司兰州石油化工研究中心项目(2008015)资

[[alternative]]Using KL Algorithm for Multi-Channel Wireless Broadcast Partitioning

[[abstract]]　　隨著行動科技時代的來臨，無線通訊網路與行動裝置技術正以飛快的速度前進與發展，使行動使用者隨時隨地都能方便地獲得想要的資訊。在無線網路的環境之下，以目前的技術來看，無線網路技術的頻寬仍比有線網路技術的頻寬小很多；因此，廣播是一項節省頻寬浪費的有效技術！　　　在多頻道的無線廣播環境中，將行動使用者所要求的資料項目平均分配到數個頻道上面，這樣一來可以縮短伺服器的廣播週期。當行動使用者所要求的資料集合分配在不同的頻道上，且位於相同的廣播時間點就會發生資料衝突。因為，發生資料衝突時，行動使用者必須等到下一個廣播週期才能再接收所要的資料項目，如此一來便會增加行動使用者資料項目的總存取時間。　　　在本文中，我們將KL演算法[18]運用於多頻道的無線廣播環境中，平均分配用戶端所請求的多重資料於多頻道上，以降低資料衝突發生的機率。從實驗結果顯示我們所使用的KL演算法可有效地降低資料發生衝突的機率：均勻分配比隨機分割法提升27%的效能、常態分配提升77%的效能，指數分配平均提升82%的效能。[[abstract]]　　With the coming time of mobile technologies, the Wireless Communication Network and the Mobile Unit Techniques are going fast step and amazingly development which make mobile technique user can get the desired information anywhere and anytime conveniently. Under the environment of wireless network, taking an overview of nowadays techniques, the bandwidth of wireless network techniques remain less than the wire network. Therefore, broadcast is a much more efficiency technique to save the use of bandwidth!　　　In the environment of multi-channel wireless broadcast, configured the required data items on several channels averagely can make the interval of broadcast shorten. Whenever the data integration of users' desired been configured on different channel but on the same time-point of broadcast will the data conflict occur. Since the data conflict occurs, the mobile users have to wait for the next broadcast interval may them receive the desired data items. This will increase the total access time of data items of mobile users'.　　　In this context, we take use of KL algorithm [18] expression at multi-channel wireless broadcast environment. Configuring the multiple data of client's required on multi-channel to decrease the rate of data conflict occurring. From the result of experience shows the KL algorithm expression what we take can effectively decrease the rate if data conflict: raising the performance of 27% at equalized configuration than random split, 77% at normalized configuration, and 82% at log configuration

Coupled generalized nonlinear Schrodinger equations solved by adaptive step size methods in interaction picture

We extend two adaptive step size methods for solving two dimensional or multi dimensional generalized nonlinear Schrodinger equation (GNLSE): one is the conservation quantity error adaptive step control method (RK4IP CQE), and the other is the local error adaptive step control method (RK4IP LEM). The methods are developed in the vector form of fourth order Runge Kutta iterative scheme in the interaction picture by converting a vector equation in frequency domain. By simulating the supercontinuum generated from the high birefringence photonic crystal fiber, the calculation accuracies and the efficiencies of the two adaptive step size methods are discussed. The simulation results show that the two methods have the same global average error, while RK4IP LEM spends more time than RK4IP CQE. The decrease of huge calculation time is due to the differences in the convergences of the relative photon number error and the approximated local error between these two adaptive step size algorithms

DBR单纵模光纤激光器波长温度调谐

报道了采用DBR方式，利用8 mm的高浓度掺Yb3+单模光纤，实现了波长为1 064 nm的单纵模调谐激光稳定输出的实验结果。该DBR谐振腔有效腔长为16 mm，输出最大功率为7.4 mW，通过半导体制冷器温控改变谐振腔的温度，实现了0.824 nm的单纵模无跳模调谐。采用光纤外差法，并利用低损耗环形器和光纤反射镜倍增延迟线长度提升测量精度的方式，测量得到激光最大线宽为4.4 kHz。单纵模激光的弛豫震荡峰位于900 kHz处，其相对强度噪声为-110 dB/Hz，当频率大于1.5 MHz时相对强度噪声为-145 dB/Hz

新疆内陆干旱区不同灌水量对长绒棉光合特性的影响

为探索新疆内陆干旱区不同灌水量对长绒棉新海14号光合特性的影响,利用小区试验,在5种灌水量(W)条件下,对其光合特性进行研究。结果表明:灌水量为7650m3/hm2时,叶片净光合速率日变化呈单峰曲线;随着灌水量的降低,其净光合速率日变化呈双峰曲线。新海14号的光补偿点为50μmol/m2·s;灌水量为2850(m3/hm2)时,其光饱和点为310μmol/(m2·s),灌水量为5475m3/hm2以上时,其光饱和点为1280μmol/(m2·s)。叶片的净光合速率及蒸腾速率随灌水量的升高而增加,气孔阻力随灌水量的升高而降低。水分利用效率随着灌水量的降低而提高,呈极显著负相关;棉花产量对灌水量极为敏感。净光合速率与蒸腾速率呈显著正相关,与气孔阻力呈极显著负相关;蒸腾速率与气孔阻力呈显著负相关。新海14号的光合作用最适宜灌水量为6945m3/hm2;灌溉的临界值为5250m3/hm2

干旱区灌溉量对长绒棉蕾铃脱落的影响

通过对地面灌溉条件下不同灌溉量和灌水量下长绒棉蕾铃脱落情况的调查,研究了灌溉量、灌水量对长绒棉全生育期、不同生育时期、不同果枝节位蕾铃脱落的影响。结果显示灌溉量过少或过多,棉花蕾铃脱落都较严重,只有灌溉量达到适宜水平,同时能够及时补充水分,蕾铃脱落才相对较低。在南疆阿克苏地区灌溉量6 000~6 200 m3/hm2蕾铃脱落率最小。棉花蕾铃脱落在花铃期比较严重,所以应注意此时棉花对水分和养分的供应。棉花中部脱落比较严重,尤其是第7果节位达到8%~9%以上

Using DWS Optical Readout to Improve the Sensitivity of Torsion Pendulum

In space gravitational wave detection missions, a drag-free system is used to keep the test mass (TM) free-falling in an ultralow-noise environment. Ground verification experiments should be carried out to clarify the shielding and compensating capabilities of the system for multiple stray force noises. A hybrid apparatus was designed and analyzed based on the traditional torsion pendulum, and a technique for enhancing the sensitivity of the torsion pendulum system by employing the differential wavefront sensing (DWS) optical readout was proposed. The readout resolution experiment was then carried out on an optical bench that was designed and established. The results indicate that the angular resolution of the DWS signal in optical readout mode can reach the level of 10 nrad/Hz1/2 over the full measurement band. Compared with the autocollimator, the sensitivity of the torsional pendulum is noticeably improved, and the background noise is expected to reach 4.5 x 10-15 Nm/Hz1/2@10 mHz. This method could also be applied to future upgrades of similar systems

模糊多專家多準則決策網路系統

出處：真理大學工業管理學

干旱内陆河灌区节水农业综合技术体系研究与集成

本课题从工程节水、农艺节水、管理节水三个方面,集成了农业高效节水、水肥盐调控、生态保护、监测与管理等关键技术,提出了干旱内陆河灌区农业节水技术集成体系与应用模式。提出了仅需根据水流推进过程确定土壤入渗参数和田面糙率系数的新方法,简化了地面灌溉设计。提出了根据土壤剖面含水率变化估算柽柳生长条件下潜水蒸发的理论方法与数学模型,为解决天然植被实际生态耗水问题提供了简易可行的方法

绿洲农业高效用水技术集成与示范

简要技术说明： 该成果围绕棉花、葡萄、小麦3大作物,从干旱绿洲区作物高效用水和提高作物水分生产效率的目标出发,研究形成了棉花高效用水技术模式3套、葡萄高效用水技术模式1套、小麦优化灌溉节水及配套栽培技术模式1套、干旱绿洲区农业高效用水管理技术模式1套,开发了15项农业节水关键技术和1套“农业灌溉决策支持系统”,筛选出节水配套抗旱小麦品种2个、抗旱棉花品种1个,制定了农业高效用水技术规程7项,研发了专利产品1项、软件著作权登记1项,人才培养12名、发表论文45篇。通过对高效灌溉技术、农艺高效用水技术、高效用水管理技术等3方面的关键技术的集成与创新,研究形成了干旱绿洲区特色作物(棉花、葡萄、..