Liquid-phase hydrogenation of bio-refined succinic acid to 1,4-butanediol using bimetallic catalysts

open access articleDevelopment of a Crotalaria juncea based biorefinery produce large quantity of waste glycerol after trans-esterification of the juncea seeds. This glycerol, after purification, is used as a substrate for producing succinic acid on a microbial route. Hydrogenation of this bio-refined succinic acid is carried out under high pressure in order to produce 1,4- butanediol (BDO) using a batch slurry reactor with cobalt supported ruthenium bimetallic catalysts, synthesized inhouse. It is demonstrated that, using small amounts of ruthenium to cobalt increases the overall hydrogenation activity for the production of 1,4-butanediol. Hydrogenation reactions are carried out at various operating temperatures and pressures along with changes in the mixing ratios of ruthenium chloride and cobalt chloride hexahydrate, which are used to synthesize the catalyst. The Ru-Co bimetallic catalysts are characterized by XRD, FE-SEM and TGA. Concentrations of the hydrogenation product are analyzed using Gas chromatography-Mass spectrometry (GC-MS). Statistical analysis of the overall hydrogenation process is performed using a Box-Behnken Design (BBD)

On-line chloride removal from ion chromatography for trace-level analyses of phosphite and other anions by coupled IC-ICPMS

This work was financially supported by a Natural Environment Research Council (NERC) Frontiers grant (NE/V010824/1) and by a Leverhulme Trust research grant (RPG-2022-313) to E.E.S.Rationale Ion chromatography (IC) combined with inductively coupled plasma mass spectrometry (ICPMS) is an ideal tool for measuring low concentrations of anionic species such as phosphite; however, the high concentration of chloride and other anions in natural solutions may negatively impact chromatographic separation and data quality. Method We developed an on-line mechanism of removing chloride from a sample within an ion chromatograph, using an additional valve and a separation column that transfers chloride to waste while phosphite and most other anions are retained. We installed this system in a coupled IC/ICPMS system (ICS6000 and Element 2 in medium-resolution mode) and determined linearity and detection limits. In addition, we measured phosphorus species by NMR for comparison as an alternative method for phosphite determination. Results Chloride was fully removed from the samples while phosphite was retained and could be analysed by IC/ICPMS. Concentrations could be measured down to 0.003 μmol/L and possibly less with good linearity over the explored range (up to 1.615 μmol/L; r2 = 0.999). In contrast, the detection limit by NMR was 6.46 μmol/L. Conclusions The on-line removal mechanism works well for simplifying sample matrices. It removes the need for costly pre-analytical sample treatment with OnGuard columns. We confirm that IC/ICPMS is the most powerful technique for quantifying phosphite in natural solutions. The new chloride-removal method may also be applicable to analyses of other anions.Publisher PDFPeer reviewe

Determination of the breakpoint and molecular diagnosis of a common α-thalassaemia-1 deletion in the Indian population

The previously described South African type α-thalassaemia-1 mutation was identified in Indian HbH patients using a polymerase chain reaction (PCR) strategy. A multiplex PCR assay was devised to detect heterozygotes and homozygotes. This α-thalassaemia-1 mutation was found to be the commonest determinant causing HbH disease in this population. In one family this mutation was found in combination with a novel splice donor mutation α2 IVS I-1 (G→A). Characterization of the breakpoint junction sequence revealed, in addition to a 23 kb deletion, that there was an addition of ~160 bp bridging the breakpoints. Similar to other deletions in the α-globin gene cluster, there is an Alu repeat-mediated mechanism for the origin of the deletion

Multistep Model Predictive Control for Cascaded H-Bridge Inverters: Formulation and Analysis

© 1986-2012 IEEE. In this paper, a suitable long prediction horizon (multistep) model predictive control (MPC) formulation for cascaded H-bridge inverters is proposed. The MPC is formulated to include the full steady-state system information in terms of output current and output voltage references. Generally, basic single-step predictive controllers only track the current references. As a distinctive feature, the proposed MPC also tracks the control input references, which in this case is designed to minimize the common-mode voltage (CMV). This allows the controller to address both output current and CMV targets in a single optimization. To reduce the computational effort introduced by a long prediction horizon implementation, the proposed MPC formulation is transformed into an equivalent optimization problem that can be solved by a fast sphere decoding algorithm. Moreover, the benefits of including the control input references in the proposed formulation are analyzed based on this equivalent optimization problem. This analysis is key to understand how the proposed MPC formulation can handle both control targets. Experimental results show that the proposal provides an improved steady-state performance in terms of current distortion, inverter voltages symmetry, and CMV

A Rare Anomaly of the Long Head of the Biceps Brachii Muscle

Introduction: Biceps brachii is a muscle of arm which brings about supination when fore-arm is flexed and flexion of elbow joint. Proximally it is attached with two heads: long and short heads. Case report: The absence of long head of biceps brachii muscle is very rare anomaly. It may be unilateral or bilateral with or without other congenital anomalies. The exact prevalence of this anomaly is unknown. This anomaly has been reported to occur as the result of an insult to the fetus during the sixth or seventh week of gestation, at which time the long head of the biceps tendon is developing.  J-GMC-N | Volume 11 | Issue 01 | January-June 2018, Page:56-5

Molecular genetics of hereditary prothrombin deficiency in Indian patients: identification of a novel Ala362→Thr (Prothrombin Vellore 1) mutation

Prothrombin deficiency is a rare (1:200 000) autosomal recessive disorder caused by diverse mutations in prothrombin gene. We have studied the molecular basis of this disorder in four unrelated Indian patients. The diagnosis was based on prolonged prothrombin (PT) and activated partial thromboplastin times and low factor II coagulant activity (FII: C) measured using a PT based assay. FII: C levels ranged between 4.7% and 17.5%. Mutations were identified in all the four patients. Five different causative mutations including four (80%) missense and an in-frame deletion (20%) were identified. One of them was a novel, Ala362→Thr aminoacid change affecting 'B' chain of α-thrombin. This mutation was present in a compound heterozygous state with a previously reported Arg-1→Gln missense change affecting pro-peptide cleavage site. Ala362→Thr occurred at a codon, evolutionarily conserved in all the 24 different prothrombins or its related serine proteases studied. Molecular modeling of this mutation was found to cause a conformational change around the region involving a catalytic triad residue His363 and a cysteine residue at codon 364. The FII: C level in this patient was 17.5%. Three other previously reported mutations were also detected in the homozygous state: Arg271→Cys in Kringle-2 region, a Glu309?Lys in 'A' chain of α-thrombin and an in-frame deletion of 3 bp (AAG) leading to Del Lys301/302 in 'A' chain of α-thrombin. This is the first report of the molecular basis of prothrombin deficiency in Indian patients and we suggest the eponym 'Prothrombin Vellore 1' for Ala362→Thr mutation

Six novel mutations including triple heterozygosity for Phe31Ser, 514delT and 516T→G factor X gene mutations are responsible for congenital factor X deficiency in patients of Nepali and Indian origin

Factor X (FX) deficiency is a rare (1 : 100000) autosomal recessive disorder caused by heterogeneous mutations in FX gene. We have studied the molecular basis this disease in six Indian and one Nepali patients. Diagnosis was confirmed by measuring the FX coagulant activity (FX: C) using a PT based assay. Six of them had a FX: C of < 1% and one patient had 24% coagulant activity. Mutations were identified in all the seven patients. These included eight (88.8%) missense and one frame-shift (11.2%) mutations of which six were novel. Three of the novel mutations, a Phe31Ser affecting 'Gla' domain and 514delT and 516T?G mutations affecting Cys132 in 'connecting region' were identified in a triple compound heterozygous state in a Nepali patient presenting with a severe phenotype. Two other novel mutations, Gly133Arg, may affect the disulphide bridge between Cys132-Cys302 in the connecting region while Gly223Arg may perturb the catalytic triad (His236, Asp282 and Ser379). The other novel mutation, Ser354Arg, involves the replacement of a small-buried residue by a large basic aminoacid and is likely to have steric or electrostatic effects in the pocket involving Lys351-Arg347-Lys414 that contributes to the core epitope of FXa for binding to FVa. Three previously reported mutations, Thr318Met; Gly323Ser; Gly366Ser were also identified. This is the first report of the molecular basis of FX deficiency in patients from the Indian subcontinent

Management of Root Knot Nematode on Tomato Through Grafting Root Stock of Solanum Sisymbriifolium

The root-knot nematodes (Meloidogyne spp) are difficult to manage once established in the field because of their wide host range, and soil-borne nature. Thus, the aim of the present study was to examine the use of resistant root stock of wild brinjal (Solanum sisymbriifolium) to reduce the loss caused by the nematodes on tomato. For the management of root-knot nematodes, grafted plant with resistant root stock of the wild brinjal was tested under farmers\u27 field conditions at Hemza of Kaski district. Grafted and non-grafted plants were produced in root-knot nematode-free soil. Around three week-old grafted and non-grafted tomato plants were transplanted in four different plastic tunnels where root-knot nematodes had been reported previously. The plants were planted in diagonal position to each other as a pair plot in 80 × 60 cm2 spacing in an average of 20 × 7 m2 plastic tunnels. Galling Index (GI) was recorded three times in five randomly selected plants in each plot at 60 days intervals. The first observation was recorded two months after transplanting. Total fruit yield was recorded from same plants. In the grafted plants, the root system was totally free from gall whereas in an average of 7.5 GI in 0-10 scale was recorded in the non-grafted plants. Fruits were harvested from time to time and cumulated after final harvest to calculate the total fruit yield. It was estimated that on an average tomato fruit yield was significantly (P>0.05) increased by 37 percent in the grafted plants compared with the non-grafted plants. Grafting technology could be used effectively for cultivation of commonly grown varieties, which are susceptible to root-knot nematodes in disease prone areas. This can be used as an alternative technology for reducing the use of hazardous pesticides for enhancing commercial organic tomato production.Journal of Nepal Agricultural Research Council Vol.3 2017: 27-3