H<inf>2</inf> Production via Ammonia Decomposition Using Non-Noble Metal Catalysts: A Review

The wide-spread implementation of the so-called hydrogen economy is currently partially limited by an economically feasible way of storing hydrogen. In this context, ammonia has been commonly presented as a viable option for chemical storage due its high hydrogen content (17.6 wt%). However, its use as an energy carrier requires the development of catalytic systems capable of releasing hydrogen at adequate rates and conditions. At the moment, the most active catalytic systems for the decomposition of ammonia are based on ruthenium, however its cost and scarcity inhibit the wide scale use of these catalysts. This issue has triggered research on the development of alternative catalysts based on more sustainable systems using more readily available, non-noble metals mainly iron, cobalt and nickel as well as a series of transition metal carbides and nitrides and bimetallic systems, which are reviewed herein. There have been some promising cobalt- and nickel-based catalysts reported for the decomposition of ammonia but metal dispersion needs to be increased in order to become more attractive candidates. Conversely, there seems to be less scope for improvement of iron-based catalysts and metal carbides and nitrides. The area with the most potential for improvement is with bimetallic catalysts, particularly those consisting of cobalt and molybdenum.Engineering and Physical Science Research Council (Grant Number EP/L020432/2), SASOL UK Ltd.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s11244-016-0653-

Ammonia decomposition over cobalt/carbon catalysts—Effect of carbon support and electron donating promoter on activity

This paper sets the new design parameters for the development of low temperature ammonia decomposition catalysts based on readily available cobalt as an alternative to scarce but highly active ruthenium-based catalysts. By using a variety of carbon materials as catalytic supports, we systematically demonstrate that microporous supports capable of stabilising small cobalt crystallites (~2 nm) lead to high catalytic activities compared to bigger nanoparticles. Additionally, the degree of graphitisation of the carbon support has a detrimental effect on the activity of the cobalt (0) active sites, likely due to their potential as an electron donator. Consequently, the addition of electron donating promoters such as cesium substantially decreases the activity of the cobalt catalysts. This relationship deviates from the trends observed for ruthenium-based catalysts with an optimum 3–5 nm size where an increase of the graphitisation degree of the support and the addition of electron donating promoters increases the ammonia decomposition activity.The authors would like to acknowledge the UK Engineering and Physical Science Research Council (grant number EP/L020432/2) and the Doctoral Training Centre in the Centre for Sustainable Chemical Technologies at the University of Bath (grant number EP/K016334/1) for funding, and SASOL UK Ltd for supporting TEB’s studentship. We would also like to thank the Research Catalysis Group at Harwell(RCaH)for access to the TEM microscopy facilities.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.cattod.2016.05.04

Hepatic trisegmentectomy and other liver resections

Trisegmentectomy, extended right hepatic lobectomy, is the removal of the true right lobe of the liver in continuity with most or all of the medial segment of the left lobe. Some important features of the operation have not been well described previously. To perform trisegmentectomy, safely, a fusion of liver tissue covering the umbilical fissure at the level of the falciform ligament must first be split open in many patients. The left branches of the portal triad structures are mobilized from the undersurface of the liver nearly to but not into the umbilical fissure. The blood supply and duct drainage of the medial segment originate within the umbilical fissure and feed back toward the right side buried in liver substance. They are found with blunt dissection just to the right of the flaciform ligament, encircled and ligated. Failure to appreciate this switch back anatomic arrangement may lead to injury of the blood supply or biliary drainage of the residual lateral segment. Parenthetically, the mirror image operation of lateral segmentectomy could result in devascularization of the medial segment if dissection and ligation were performed within the umbilical fissure instead of well to the left of this landmark. In most trisegmentectomies, the left portion of the caudate lobe is not removed. This small piece of tissue is interposed between the lateral segment and the inferior vena cava into which it drains by small tributaries. If the left portion of the caudate lobe is to be excised, it is necessary to ligate the last two posteriorly running branches before the main left trunks of the portal triad structures reach the umbilical fissure. Once this step is taken and if the caudate removal is completed, the remaining lateral segment usually has only one remaining outflow, that of the left hepatic vein. The other principles of trisegmentectomy are the same as with less radical subtotal hepatic resection. These include vascular suture closure of the main outflow veins, avoidance of parasegmental planes that leave behind a strip of devitalized tissue, preservation of intersegmental or interlobar veins, omission of techniques that sew shut or otherwise cover the raw surface of the remnant and provision of adequate drainage of dead space. After trisegmentectomy and also after true lobectomy, this last objective is usually met by leaving part of the operative incision open. Using thse guidelines, there has been no mortality with 27 hepatic resections carried out since 1963, including 14 trisegmentectomies

The comparative in vitro and in vivo activity of antilymphocyte serum raised by immunization with thymic, splenic, and lymph node lymphocytes

Rabbit ALS was raised against the splenic, thymic, and lymph node lymphocytes of inbred Fischer rats. The different antisera had the same ability to induce lymphopenia or to protect auxiliary cardiac homografts from rejection after transplantation from Wistar-Furth donors to Fischer recipients. There was a difference in the toxicity of the agents in that the antispleen and antithymus sera caused thrombocytopenia. The severity of this complication seemed related to the degree of platelet contamination of the rat cell suspensions originally given to the rabbits. The thrombocytopenia can be at least partially avoided by cleaning up the immunizing antigen as well as by platelet absorption of the resulting ALS. © 1969

Hepatic transplantation, 1975.

This report reviews experience with 97 patients given liver transplants. We regard out survival statistics as unsatisfactory, but fell they should encourage further work since 22 patients have survived at least one year with a maximum survival of 5 13 YEARS. The Achilles' heel of liver transplantation os bile duct reconstruction. We presently rely upon Roux-en-Y reconstruction, or alternatively, duct-to-duct anastomosis with a T-tube stent. The prime indication for liver replacement is non-neoplastic liver disease, but a favourable malignancy for treatment may prove to be small intrahepatic duct cell carcinomas

Are long term care facilities (LTCF) prepared for H1N1?

Background: A 2007 survey of Midwestern LTCF suggested that less than 25% had a written pandemic influenza response plan. Upon request from a rural nursing home, we developed pandemic influenza planning recommendations for LTCF. Methods: In September 2009, we mailed written recommendations to 144 LTCF in West Texas and New Mexico and included a survey with questions about the facility, facility preparedness, and the usefulness of the recommendations. We performed standard statistical analysis on returned surveys. Results: 24/143 (17%) facilities returned the survey, indicating that they had read (21) or planned to read (3) the recommendations. 15/23 (65%) of surveys were from facilities in rural communities. 16/23 (70%) of facilities already had a written pandemic influenza response plan. Most facilities had stockpiled some supplies: gloves (19/24, 79%), alcohol based hand washes (18/24, 75%), surgical masks (16/24, 67%), and N95 masks (8/24, 33%). 18/24 (75%) had discussed obtaining vaccine with the health department, 17/24 (71%) had instituted staff education and training, and 15/24 (63%) had developed written material for staff and families. 11/24 (49%) anticipated staffing shortages; most planned to use overtime, non-clinical staff, and volunteers to provide for clinical services during staff shortages. Only 3/24 (13%) of these facilities planned to use commercial agencies for staffing shortage. Of those who had read the recommendations, 100% found them helpful or very helpful. The most frequently cited anticipated changes based on the recommendations included changing isolation procedures (11/24, 46%) and vaccination program (9/24, 38%); review of staff absenteeism policies (38%); and revision of the written pandemic influenza plan (38%). There were no statistical differences between facilities in urban and rural communities with regard to the presence of a written plan, staff training, discussions with the health department, stockpiling of supplies, or anticipated changes based on review of the recommendations. Conclusions: This small survey suggests that LTCF may be better prepared for pandemic influenza than they were two years ago. These facilities found that mailed written planning recommendations were helpful, and would result in changes to deal with H1N1 pandemic influenza