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Reproduced from New J. Chem., 2023, 47, 231-237 with permission from the Royal Society of Chemistry., https://doi.org/10.1039/d2nj04361k, Ionic clathrate hydrates (ICHs) have been applied to thermal storage materials, which can be utilized as unusual thermal energy sources. In the present study, we developed a novel ICH including tri-n-butyl(cyclobutylmethyl)phosphonium bromide (P444(1c4)-Br) as an unprecedented guest species. The highest equilibrium temperature and the dissociation enthalpy of P444(1c4)-Br ICH were 279.5 ± 0.1 K and 202 ± 2 J g−1, respectively, at the mole fraction of 0.0255 ± 0.0008. The highest equilibrium temperature of P444(1c4)-Br ICH was slightly lower than that of the tetra-n-butylphosphonium bromide (P4444-Br) ICH. The dissociation enthalpy of P444(1c4)-Br ICH was larger than that of other ICHs with similar highest equilibrium temperatures. Cyclic hydrocarbon groups, together with normal, branched, saturated, and unsaturated hydrocarbon chains, can be one of the options for tuning the equilibrium temperature of ICHs.

Azuma S., Shimada J., Tsunashima K., et al. Equilibrium Phase Relations and Dissociation Enthalpies of Tri- n-butylalkenylphosphonium Bromide Semiclathrate Hydrates. Journal of Chemical and Engineering Data, 67, 6, 1415 - 1420, May 25, 2022, © 2022 American Chemical Society. https://doi.org/10.1021/acs.jced.2c00146., Semiclathrate hydrates (SCHs) have received attention as thermal storage materials because of their equilibrium temperature and relatively large dissociation enthalpy. The alkyl length of quaternary onium cations significantly affects the equilibrium temperature and dissociation enthalpy of quaternary onium salt SCHs. To investigate the effects of the double bond introduced in onium cations, in the present study, the thermodynamic stability of tri-n-butylalkenylphosphonium bromide (P444(alkenyl)-Br: alkenyl = 3-butenyl (3═1) or 4-pentenyl (4═1)) SCH was investigated. The equilibrium temperatures and the dissociation enthalpies were determined to be (277.5 ± 0.1) K and (199 ± 2) J/g for P444(3═1)-Br SCH, and (274.8 ± 0.1) K and (188 ± 2) J/g for P444(4═1)-Br SCH. The equilibrium temperatures of P444(3═1)-Br SCH and P444(4═1)-Br SCH were lower than those of the corresponding normal alkyl SCHs (P4444-Br and P4445-Br), although the equilibrium temperature of tri-n-butylallylphosphonium bromide SCH was higher than that of the P4443-Br SCH.

Jin Shimada, Moe Yamada, Atsushi Tani et al. Thermodynamic Properties of Tetra-n-butylphosphonium Dicarboxylate Semiclathrate Hydrates. Journal of Chemical & Engineering Data, 67 (1), 67-73, January 13, © 2022 American Chemical Society. https://doi.org/10.1021/acs.jced.1c00741, Semiclathrate hydrate (SCH) is one of the phase change materials suitable for cold energy storage. Thermodynamic properties of SCHs, such as an equilibrium temperature and the dissociation enthalpy, depend on the size and shape of the guest substances. In the present study, to reveal the effects of steric conformations of the guest anions on the thermodynamic properties of SCHs, tetra-n-butylphosphonium dicarboxylate (TBP-DC) SCHs, where the anion was oxalate (TBP-Oxa), malonate (TBP-Mal), succinate (TBP-Suc), glutarate (TBP-Glu), maleate (TBP-Male), or fumarate (TBP-Fum), were investigated. TBP-Oxa, -Mal, -Suc, and -Fum SCHs had similar equilibrium temperatures, whereas the equilibrium temperatures of TBP-Glu and -Male SCHs were higher. This suggests that the size and conformation of glutarate and maleate anions are appropriate for the cage structures of SCHs. Moreover, we compared the equilibrium temperatures of TBP-Suc, -Male, and -Fum SCHs because TBP-Suc, -Male, and -Fum have similar anion structures. The equilibrium temperature of TBP-Suc SCH was similar to that of TBP-Fum SCH, whereas TBP-Male SCH showed a higher equilibrium temperature. This result implies that the succinate anion is accommodated in the trans conformation, similar to the fumarate anion, in the hydrate cages.

Clathrate hydrate as well as ice has been spotlighted as promising materials to investigate the properties of hydrogen-bonded networks formed by the water molecules. In the semiclathrate hydrate (SCH, a kind of clathrate hydrate) consisting of host water molecules and guest quaternary onium salts, the anion takes part in the hydrogen-bonded networks with the water molecules. In the present study, we measured the electrical conductivity and electrical relaxation time in the single-crystalline tetra-n-butylammonium bromide (TBAB) SCH by electrochemical impedance spectroscopy. The results clearly revealed that the conduction carrier was proton. The electrical relaxation time of proton conduction in TBAB SCH was similar to the reorientation time of the water molecules in TBAB SCH estimated by the results of nuclear magnetic resonance.

Phase equilibrium (temperature–composition) relations of the tetra-n-butylphosphonium trifluoroacetate (TBP-TFA) + water binary system including solid (semiclathrate hydrate, SCH)-liquid equilibria and liquid-liquid equilibria were investigated. Phase diagram of TBP-TFA SCH exhibited peritectic behavior. The maximum decomposition temperature (peritectic temperature) of TBP-TFA SCH at atmospheric pressure were 275.9 ± 0.1 K. The stoichiometric composition of TBP-TFA SCH was located at the mole fraction of 0.027 ± 0.002. The decomposition enthalpy of TBP-TFA SCH was 199 ± 2 J/g. At temperatures above the lower critical solution temperature (LCST), the liquid-liquid phase separation appeared. Interestingly, the composition at the LCST was 0.026 ± 0.002, which is very similar to the stoichiometric composition of TBP-TFA SCH. It implies that both cluster-based solution structures are similar.

The case was a man in his 60s. With a complaint of loss of appetite, a peripheral type 3 lesion was found from the lower body of the stomach to the vestibule, and a biopsy revealed poorly differentiated adenocarcinoma. CT examination revealed that the tumor had invaded the left lobe of the liver and the transverse colon, and that the para-aortic lymph nodes were swollen and multiple nodules of the gastrocolonic mesentery were found. After 6 courses of S-1 plus cisplatin(SP)therapy were performed, the tumor shrank and lymph node swelling and nodule disappearance were observed. Laparotomy and pyloric gastrectomy, partial liver resection, D2 dissection, and Roux-en-Y reconstruction were performed. As a result of histopathological examination, R0 was resected. After the operation, S-1 was taken orally for 1 year, and no recurrence or metastasis has been observed 6 and a half years after the operation. This time, we report a valuable case in which SP therapy was successful for unresectable gastric cancer and long-term survival was obtained by conversion surgery.

Thermodynamic stabilities of tetra-n-butylphosphonium acetate (TBP-Ace) semiclathrate hydrates in the presence of methane (CH 4 ), carbon dioxide (CO 2 ), nitrogen (N 2 ), or ethane (C 2 H 6 ) were measured in a pressure range up to approximately 5 MPa. The dissociation temperature of TBP-Ace + CH 4 , TBP-Ace + CO 2 , and TBP-Ace + N 2 semiclathrate hydrates increased drastically with an increase in pressure, which means that CH 4 , CO 2 , and N 2 molecules occupy the vacant cages of the TBP-Ace semiclathrate hydrate. On the other hand, the C 2 H 6 molecules hardly occupied the cages, resulting in small pressure dependence of the dissociation temperature. Raman spectra and powder X-ray diffraction patterns of TBP-Ace + CO 2 semiclathrate hydrate reveal that the phase transition occurs at 1.04 ± 0.04 MPa and 285.88 ± 0.05 K. One of the possible reasons why the phase transition occurs is that the carbonate and/or hydrogen carbonate anions derived from the CO 2 molecules are replaced with some of acetate anions in the TBP-Ace + CO 2 semiclathrate hydrate.

This paper reports phase equilibrium (temperature–composition) relations of semiclathrate hydrates formed from tetra-n-butylphosphonium propionate (TBP-Pro) and butyrate (TBP-But) + water systems. Their maximum solid–liquid phase equilibrium temperatures at atmospheric pressure were located at (288.75 ± 0.06) K and the mole fraction x1 = 0.035 ± 0.001 and (287.01 ± 0.06) K and x1 = 0.028 ± 0.001, respectively. They showed equilibrium temperatures higher than those of tetra-n-butylphosphonium formate, acetate, and lactate semiclathrate hydrates. The dissociation enthalpies of TBP-Pro and TBP-But semiclathrate hydrates were (190 ± 5) J·g−1 and (204 ± 5) J·g−1, respectively. The temperature difference between formation and dissociation, that is, the maximum allowable degree of supercooling, was (17.7 ± 1.5) K for TBP-Pro semiclathrate hydrate and (15.4 ± 1.4) K for TBP-But one.

Phase equilibrium (temperature–composition) relations of tetra-n-butylphosphonium formate (TBP-For), acetate (TBP-Ace), and lactate (TBP-Lac) semiclathrate hydrate systems have been measured. The highest equilibrium temperatures of TBP-For, TBP-Ace, and TBP-Lac semiclathrate hydrates were 280.9, 284.6, and 283.8 K at the atmospheric pressure, respectively, where the composition of tetra-n-butylphosphonium carboxylate was approximately 0.035 ± 0.001 (mole fraction) in every system. The dissociation enthalpies of tetra-n-butylphosphonium carboxylate semiclathrate hydrates were measured by differential scanning calorimetry. The dissociation enthalpies of TBP-For, TBP-Ace, and TBP-Lac semiclathrate hydrates were (187 ± 3), (193 ± 3), and (177 ± 3) J·g–1, respectively.

Semiclathrate hydrate (SCH) is one of the phase change materials suitable for cold storage. The thermodynamic properties of SCHs, such as an equilibrium temperature and a dissociation enthalpy, depend on the size and shape of guest substances. In this study, to reveal the effect of cation size and shape on the thermodynamic properties, tri-n-butylalkylphosphonium bromide (P444R-Br) SCHs, where the alkyl group was n-propyl (R = 3), n-butyl (R = 4), n-pentyl (R = 5), i-butyl (R = i-4), i-pentyl (R = i-5), or allyl (R = Al)), were investigated. The branched alkyl groups (R = i-4 or i-5) raised the equilibrium temperature, whereas the shorter alkyl groups (R = 3 or Al) lowered one. Except for P4445-Br and P444(Al)-Br SCHs, the other P444R-Br SCHs had the same orthorhombic structure. Among the orthorhombic systems in the present study, the semiclathrate hydrate with a higher equilibrium temperature had a larger dissociation enthalpy.

Reports of emergency surgical repair of a retrosternal hernia causing respiratory failure in an adult are rare. We treated an 82-year-old man who had been suffering breathlessness upon exertion, some speech difficulty, and, most recently, visual hallucinations. He had consulted a physician who ordered an arterial blood gas test, which revealed hypoxemia, and thoracoabdominal computed tomography (CT), which revealed a hernia that was compressing the pulmonary parenchyma. Over the next 30 days, the hernia worsened, acute respiratory failure developed, and the patient was transferred to our hospital by ambulance. The patient presented to us not only with respiratory failure but also a decreased level of consciousness. CT performed upon admission revealed prolapse of the transverse colon from the posterior surface of the sternum to the right thoracic cavity, left deviation of the mediastinum, and compression of the pulmonary parenchyma, which we believed to be the cause of the hypoxemia. With the hernial orifice appearing to be on the right, a Morgagni hernia was diagnosed. Emergency surgery was deemed necessary. An epigastric midline laparotomy incision was placed, and we observed a retrosternal hernia, with an enlarged foramen of Morgagni measuring 70mm × 50 mm as the hernial orifice. The hernia contained portions of the greater omentum and transverse colon. We returned the contents to the peritoneal cavity manually closed the hernia orifice by simple suturing and reinforced the repair with a mesh patch. With signs of cardiac failure developing, temporary noninvasive positive-pressure ventilation was instituted from postoperative day 5 to postoperative day 11, but the patient’s general condition improved thereafter, and he was discharged on postoperative day 29.

はじめに:結腸膀胱瘻の原因は憩室炎が最も多いが，大腸癌，膀胱瘻によるものもあり，術式決定には注意を要する．症例:77歳，男性．頻尿を主訴に受診し，難治性膀胱炎であったため精査を行うと，CTではS状結腸と膀胱に浸潤する腫瘤影があり，膀胱内に含気を認めた．注腸ではS状結腸に全周性狭窄があり，その口側に多発する憩室とS状結腸膀胱瘻を認めた．下部消化管内視鏡・膀胱鏡では病変の観察が困難で，術前に癌の診断はつかなかった．治療・診断:S状結腸切除+膀胱部分切除を施行し，病理で壁外発育型大腸癌，結腸膀胱瘻の診断となった．考察:内瘻形成性大腸癌は局所進行癌であるがリンパ節転移陽性率は他臓器浸潤癌に比べ低く，生物学的悪性度に差があると考えられる．今回，壁外発育型S状結腸癌が膀胱瘻を形成した1例を経験したため，文献的考察を加え報告する．

We have previously shown that a vesico-amniotic shunt (V-A shunt) produces fibrotic bladders with poor compliance in normal fetal lambs. We hypothesized that using a ventriculo-peritoneal shunt (V-P shunt) as a V-A shunt in normal bladders may preserve the filling/emptying cycle and normal bladder development.The V-A shunting in normal fetal lambs was performed at 74 days of gestation using a V-P shunt (group A) and a free-draining shunt tube (group B). Sham-operated lambs were used as controls (group C). They were all delivered at term (145 days), and the pressure-volume curve, bladder volume, and histologic features of the bladder wall were compared.The mean bladder volume in group B (n = 5), 5 +/- 2.4 mL, was significantly smaller (P.01) than that in group A (n = 6), 53 +/- 14 mL, and group C (n = 10), 57.3 +/- 12 mL. The bladder wall thickness in group A was 338 + 94.2 microm; group B, 741 +/- 128 microm; and group C, 374 +/- 120 microm. Group B bladders had very poor compliance with thick bladder wall (P.01). Histologically, group B bladders showed prominent submucosal fibrotic change, but group A bladders were similar to controls.This study shows that a pressure-limited shunt tube for V-A shunting preserves the normal fetal bladder development.

Ionic liquids (ILs) have been developed for a wide variety of electrochemical applications due to their unique physicochemical properties such as favorable solubility of organic and inorganic compounds, relatively high ionic conductivity, no measurable vapor pressure, high thermal stability, low flammability, etc. Another advantage of ILs is a designability of the ion structures. Although many kinds of ILs have been already investigated, phosphonium-based ILs have rarely been proposed. We have previously designed and synthesized the phosphonium ILs together with typical anion species such as bis(trifluoromethylsulfonyl)amide (TFSA) and bis(fluorosulfornyl)amide (FSA) anions.1,2 On the other hand, interests in ILs consisting of carboxylic acid based anions have been increasing in recent years. In this work, we synthesize the ILs based on quaternary phosphonium cations (tetraethylphosphonium, P2222 +, and tetrabutylphosphonium, P4444 +) in combination with carboxylate anions such as formate (HCO2 -), acetate (MeCO2 -) and propionate (EtCO2 -), characterizing the physicochemical and electrochemical properties of the ILs as a new family of IL-based electrolyte. The preparation of the phosphonium ILs was carried out by neutralization reactions of the precursor phosphonium hydroxides with the carboxylic acids. The obtained ILs were dried under high vacuum for at least 10 h at 60◦C. We also prepared the corresponding ammonium salts by the same procedure for comparison. The physicochemical and electrochemical properties such as conductivity (ac impedance method), viscosity (a cone-plate type viscometer), density, melting point (DSC), thermal decomposition temperature (TGA) and electrochemical window (linear sweep voltammetry using a conventional three-electrode cell) were measured under dry argon atmosphere. Table 1 summarizes the physicochemical properties of the ILs obtained in this work. The almost compounds were low-melting white solids; however only P4444-HCO2 became a liquid at ambient temperature. The conductivity and viscosity of P4444-HCO2 depended on temperature, showing the Arrhenius-type convex curve behaviors. This means a typical electrolyte behavior generally observed in IL media. P4444-HCO2 showed the lowest viscosity and highest conductivity in the three P4444-based phosphonium salts, which might be attributed to the anion sizes of the three phosphonium salts. It should be noted that the thermal decomposition temperatures of the phosphonium salts were much higher than those of the corresponding ammonium salts, revealing the high thermal stability of the carboxylic anion based phosphonium ILs (Fig. 1). In the electrochemical measurements, it was found that P4444-HCO2 had a high cathodic stability similar to those of the TFSA- and FSA-anion based phosphonium ILs. On the other hand, relatively low anodic potential window up to 0.7 V vs. Ag/Ag+ was observed, which seems likely to be due to the anodic oxidation of formate anion. References 1. K. Tsunashima and M. Sugiya, Electrochem. Commun., 9, 2353 (2007). 2. K. Tsunashima, A. Kawabata, M. Matsumiya, S. Kodama, R. Enomoto, M. Sugiya and Y. Kunugi, Electrochem. Commun., 13, 178 (2011). Figure 1