Delaware Method Improvement for the Shell and Tubes Heat Exchanger Design

In this paper the Delaware Method published in 1963 is analyzed and upgraded with using correction factors which take into account the undesirable currents of the mean flow. However, this method presents graphically these correction factors which imply an impediment to fulfill the software calculations. Thus, the equations corresponding to the correction factor equations and a Fortran 77 numerical program were established. This system is given to explore different design alternatives in order to find the optimal solution to each proposed problem. The results of this work was a simple software that can perform calculations with the introduction of parameters depending only on the geometry of the heat exchanger, i.e., geometry, temperature and fluid characteristics eliminating the human errors and increasing the calculations speed and accuracy.

海外投资指南系列美国特拉华州State of Delaware

特拉华州(State of Delaware)正处于美国的东海岸、纽约市及华盛顿之间、费城正南方的战略位置。1609年亨利.赫德森发现的特拉华湾,从1638年到1655年特拉华由瑞典人占领并作为新瑞典一部分。1787年12月7日,它第一个复决通过目前美国宪法而最早加入现在美国联邦体系,获得了美国第一州(The First State)的称誉。

Investing in Strategies to Accelerate Conservation and Measure Impact in the Delaware River Watershed

The Delaware River watershed provides drinking water to over 15 million people, critical habitat for plants and animals, including many threatened and endangered species, and recreational and economic enterprise valued at $10 billion per year in direct wages. Water quality and associated economic, environmental and social values have improved dramatically since the 1950s when the lower portion of the river was declared a dead zone during parts of the summer due to excessive inputs of domestic and industrial waste. The question today is how to ensure that progress continues in the face of persistent and growing threats to water quality. Recognizing the challenges facing the watershed, over 40 of the leading conservation groups in this 13,000 square mile region are pursuing a 10-year strategic initiative focused on water quality through the Delaware River Watershed Initiative, a conservation program advancing a combination of place-based work in watershed protection, restoration, education, collaboration and innovation through collective impact. This paper serves as an invitation for broader strategic involvement to accelerate watershed protection and restoration;it also is a springboard for stakeholders to set an agenda for ensuring that the Delaware River watershed delivers clean water for humans, plants and animals. The paper identifies eight “clusters” of sub-watersheds, constituting approximately 25 percent of the total Delaware Basin, where analysis has shown that investment in water quality could deliver significant returns. Diverse geology, land use, development patterns, population density and en-vironmental stressors are present throughout these sub-watershed clusters. Focusing conservation actions in these places contributes directly to local water quality, and by fostering experimentation and innovation, it also cultivates a wide range of effective approaches for scaling up investment across the Delaware River watershed and beyond. This paper emphasizes five strategies for investing in protection of high quality waters and restoration of impaired waters: 1. protect forested headwaters to maintain high water quality;2. manage agricultural lands to reduce polluted runoff and increase groundwater infiltration;3. implement best practices and new financial incentives to reduce urban stormwater pollution through natural processes;4. increase the evidence base for watershed protection by monitoring trends in water quality and assessing project impacts;5. improve policy and practice through applied research focused on water quality outcomes. These strategies demand place-based work, and the Delawre River Watershed Initiative will focus on advancing these efforts through the cooperation of organizations located in the eight distinct watershed clusters. Proceeding downstream from the headwaters, the eight landscapes are: Pocono Mountains and Kittatinny Ridge;New Jersey Highlands;Upper Lehigh River;Middle Schuylkill River;Schuylkill Highlands;Brandywine and Christina Rivers Upstream;Suburban Philadelphia;and Kirkwood-Cohansey Aquifer (comprising New Jersey’s Bayshore;and Pine Barrens). These clusters bring together many of the most ecologically valuable and significantly impaired areas of the watershed. They are strategically located where strong organizations and critical natural vatues provide measurable opportunities for advancing local water quality while having regional impact. The selection of areas and strategies was based on research and planning undertaken by the Open Space Institute (OSI) and the Academy of Natural Sciences of Drexel University (ANSDU} with support from the William Penn Foundation. Researchers at OSI and ANSDU were joined by the National Fish and Wildlfe Foundation (NFWF) in engaging over 40 organizations working across the eight sub-watershed clusters to develop collaborative plans for implementing and measuring local conservation strategies essential to the long-term health and vibrancy of the region. These implementation plans tackle major threats to water quality and include strategies to track progress and share lessons learned. The plans provide a framework for public agencies and philanthropic funders seeking to pursue targeted watershed protection outcomes supported by monitoring, technical assistance and ongoing communications. Organizations large and small, public and private, are invited to read this paper and consider this program as an opportunity to align investment for greater impact and help ensure a bright future for the Delaware River watershed.

A Petrophysical Approach to Evaluation from Measured While Drilling Gamma Ray, Case Study in the Powder River and Delaware Basins

One of the most common subsurface data sets that is easily accessible and often underutilized is the acquired measuring while drilling (MWD) gamma ray (GR-GAPI) log. Data is acquired from a given gamma ray tool positioned within the drill string and pulsed up to the surface through the mud column in the wellbore. Typical use of the data is for subsurface geologists, drillers and others to correlate the data to known stratigraphic signatures and steer wells through horizontal target zones. Through that correlation, an association to the geologic stratigraphic column can be made and the team of subsurface scientists adjusts where, how fast, and why they choose to continue drilling. The technique of correlation applies to both the conventional and unconventional application. In the unconventional application, the data is also typically acquired along the length of the horizontal wellbore. From a petrophysical standpoint, just acquiring a gamma ray can limit the amount of information and ability to fully evaluate the properties along the length of the well. In this study, we share and demonstrate how to utilize the MWD GR for petrophysical evaluation beyond just a volume of shale or volume of clay interpretation. The workflow will allow full integration of a comprehensive petrophysical evaluation that can then be utilized to support all subsurface understandings and modelling efforts.

蝴蝶之吻DELAWARE

第一次听到来自挪威的Delaware乐队的歌曲时总想到那部灰色阴暗的动画《死亡代理人》,主唱高亢阴柔的嗓音,华丽大气的编曲,激情澎湃的吉他,很符合那动画颓废绝望的主题.……

大庆萨尔图机场鸟类调查与鸟撞防治对策

2010年10月～2011年10月,对大庆萨尔图机场及周边生境的鸟类种类和数量进行了调查,调查共记录到鸟类15目29科89种,其中夏候鸟57种,约占鸟类总数的64.0%;旅鸟8种,约占鸟类总数的9%;冬候鸟6种,约占鸟类总数的6.7%;留鸟18种,约占鸟类总数的20.2%,在机场飞行区内发现鸟类20种。采用Geo InSight国际有限公司根据合同与美国空军共同开发的US BAM的避鸟模型,对大庆萨尔图机场飞行区内鸟类进行危险指数测定及排序,以便驱鸟人员明确对飞机构成威胁的鸟类种类,从而达到有针对性地驱除危险指数高的鸟类的目的。

美采用计算机方法研究乙烯环氧化反应机理和催化剂设计

美国Delaware大学通过理论计算和实验方法，研究了乙烯环氧化反应机理和催化剂设计，设计出的催化剂比目前工业应用的银基催化剂具有更高的选择性。

Perceptions of Beach Stewards and Information Needs for Shorebird Stopover Sites Vary as a Function of Visitor Interests: Improving Stewardship Programs in Coastal Landscapes

Many studies have demonstrated that some of the activities of people can disturb nesting and foraging birds, particularly along coasts and estuaries. Some managers respond to human disturbance of sensitive species by closing beaches, but most have stewards monitor and restrict access to beaches or portions of beaches. Yet little is known about the type of visitor or their perceptions of beach stewards. This paper explores the general acceptance of beach stewards and their role in conservation of red knots (Calidris canutus rufa), other shorebirds, and horseshoe crabs (Limulus polyphemus) along the Delaware Bay (New Jersey) beaches by interviewing 279 visitors during the stopover period. While most people came to see the shorebird and horseshoe crab spectacle (60%), many came for the scenery, tranquility, and recreation. Just over half of the people interviewed said that the stewards were helpful (58%), although most of those that answered this question later said that they provided conservation value (86%), but only 40% said they relied on the stewards for information. On a Likert rating scale of 1 to 5 (the highest value), the mean rating for whether it was important for stewards to be present was 3.87 ± 0.09, and the rating for the presence of stewards who can provide information was 3.71 ± 0.11. In contrast, protection of shorebirds was rated a mean of 4.79 ± 0.04. There were significant visitor type differences in how important stewards were, but not in the importance of stewards who can provide information. Fishermen, recreationists, and people coming for scenery and tranquility rated the presence of stewards higher than those visitors who were interested in either shorebirds or crabs (or both). Ratings also differed significantly as a function of age and gender;older adults and females rated characteristics higher than did people under 30 years and males. Information needs identified by stewards are also discussed. These data can be used by the managers developing a strategy for conservation of shorebirds and other species sensitive to disturbance, and for the implementation of an effective stewardship program.

遗传-模拟退火算法优化设计管壳式换热器

依据Bell-Delaware法对壳程流体进行压降和传热的计算,选择管径、管长、折流挡板数等结构参数作为主要设计变量,参考了美国管式换热器制造商协会(Tubular Exchanger Manufacturers Association,TEMA)标准作为相关约束条件,以换热器的年度总费用最低为目标函数,建立了管壳式换热器优化设计数学模型,并基于遗传-模拟退火算法(GA-SA)进行求解。文献算例的对比结果表明:算法能较好地权衡换热器的换热面积费用和泵的操作费用并搜索到全局最优解,从而获得总费用较低的换热器主要结构参数。针对一个实际工程项目,考虑换热器设计裕度要求,计算结果与商业化软件HTRI的预测值接近,说明所设计的换热器实际可行。同时克服了HTRI需要设计者的经验确定设计变量和无法保证经济性最优的不足。