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A review of coreflood experiments for chemically enhanced oil recovery (EOR) is presented in this paper, particularly surfactant-polymer (SP) and alkali-surfactant-polymer (ASP) processes. The objective of this review is to gain a general outlook and insight from coreflood experiments injecting SP or ASP slug as tertiary recovery. The discussion is separated into sections based on relevant core and fluid properties as well as surfactant selection and SP/ASP slug design and their impact on incremental recovery. Most studies in this review have been published within the last twenty years but few older coreflood works have been included for benchmarking. Parameters in each reviewed study have been summarized in tables to help readers gain detailed observation. Lessons learned from these past experiments should help other chemical EOR practitioners or students of the field in benchmarking or improving the outcomes of their future SP/ASP experiments.

Although an enhanced magnetoresistance (MR) has been observed in many Co2-based Heusler alloys by promoting their structural ordering from B2 to L21 by post-annealing at higher temperatures (Tann > 500 °C), it is desirable to search for other Heusler alloys that crystallize in L21-order below 300 °C, as the maximum Tann is restricted for processing devices. For Co2MnZ (Z = Ge, Sn) Heusler alloys, an L21-order is expected to appear even in the as-deposited state or by a low-temperature annealing process due to their very high L21 to B2-order transition temperature (>1500 K). Here, epitaxial Co2MnZ films were grown on MgO (001) substrate at room temperature (RT) and post-annealed at Tann = 200–500 °C. Interestingly, as-sputtered films exhibit L21-ordering, which improves systematically upon increasing Tann. The spin-polarization of electric current (β) was estimated at RT using nonlocal spin-valve (NLSV) devices by measuring the spin-accumulation signal in a copper (Cu) channel. It was found that at Tann = 300 °C, the β value of Co2MnGe films is higher (∼0.65) than that of Co2FeGe0.5Ga0.5 films due to a higher degree of L21-order, which makes the Co2MnGe alloy a promising ferromagnetic electrode for spintronic device applications.

Background: Brachial plexus is a network of nerves that controls the upper limb. Unfortunately, it can be injured easily which is called brachial plexus injury (BPI). It can cause disability. Until now, the epidemiology of BPI in Indonesia is still lacking. The aim of this study was to describe the characteristics of patients with BPI in Bandung, in order to increase knowledge and attention of health care provider and community to prevent BPI. Methods: This was a descriptive retrospective study. Data from medical records of patients with BPI who underwent electromyography (EMG) in Neurophysiology Laboratory Dr. Hasan Sadikin General Hospital, Bandung from 2003 to 2012 were collected. The data included age, sex, mode of injury, affected side and distribution of paralysis. Collected data were presented as percentages shown in tables. Results: A total of 91 cases were collected during study period, which consisted of 69 males and 22 females (76% vs. 24%). Most of them were in productive age group (11−20 years and 21−30 years). The main cause of brachial plexus injury was traffic accident (76%), followed by birth injury. Distribution of paralysis was mostly in postganglionic area of cervical (C)5, C6, C7, C8 and thoracal (T)1 (67%). Around two third of the cases involved the right side of upper limb. Conclusions: The study showed that most of patients with BPI are male in their productive ages. Traffic accident is the most common cause, and the most affected side is the right side of upper limb.

The purpose of this study was to introduce the game of small ball to elementary school students specifically in table tennis with a modification of the tool in the form of a table size that fits the body of elementary school children. This research method is development (Research and Development). The population of the research is sixth grade students at State Elementary Schools in Patumbak District, Deli Serdang Regency. The validation results of the expert questionnaire assessment were declared valid and usable with the percentage of media experts obtained at 83% in the valid category. Meanwhile, the percentage value from the meter expert was obtained at 80% in the valid category. Results of the questionnaire instrument assessment given to students during initial testingIt is known that the score obtained was 82% which was in the 80%-100% interval in the valid category. Results of the questionnaire instrument assessment given to students at the time large scale trialsIt is known that the score obtained was 83% which is in the 80%-100% valid category interval.So it can be said that teaching media products based on tool modification in table tennis games meet the criteria or are suitable for use by elementary school students as learning media. Conclusion, 1.The ideal size for mini table tennis has been created for class VI students at State Elementary Schools in Patumbak District. 2. Mini table tennis can be used by teachers and students in the physical education learning process in elementary schools.