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Staghorn renal calculi are large, branched stones in the kidney that partially or completely fill the renal pelvis and renal calyces. Percutaneous nephrolithotomy (PCNL) is the gold standard treatment for staghorn calculi. However, we report a retrograde intrarenal surgery (RIRS) performed to treat a staghorn calculus in a patient with a solitary kidney and a deformed urinary tract. The 37-year-old male patient presented with right-sided lumbar pain. The computed tomography (CT) scan found a solitary kidney on the right side with an opaque 4.5 cm × 2.4 cm renal stone and grade I hydronephrosis. Additionally, a urinary tract deformity was observed, and it was secondary to the deformity of the pelvis caused by a previous pubis fracture, which significantly increased the risk and the difficulty of intrarenal surgery. A total number of 3 sessions of RIRS were conducted, and the patient was discharged 3 days after each session on average. The postoperative X-ray exam of the third session revealed that the renal stone was completely removed. The patient recovered well without any complications. This case demonstrates that RIRS is a safe and effective treatment of staghorn calculi with the presence of urinary tract deformation. This suggests RIRS may be of particular interest in minimizing the procedure-related damage of a solitary kidney.

The Qilian Mountain permafrost is the only place where gas hydrate occurs onshore China at present and its gas hydrate distribution is very complex and irregular. What patterns affecting th...

Small molecular (SM) semiconductors with sufficient solubility and high performance are highly desired in solution-processed organic electronics. In order to address the poor solubility that a reported high performance molecular semiconductor (BDT(ThBTTh)2) with a benzodithiophene (BDT) core and two thiophene-benzothiadiazole-thiophene arms (ThBTTh) suffers from, two additional hexyl side chains have been designed into its scaffold and different attaching fashions yield two new SM semiconductors, SM1 and SM2. The integration positions in SM1 are terminal thiophene units, while that of SM2 are located on the inner thiophene units neighbor to the central BDT unit. With expectation, the so-prepared SM1 and SM2 possess much better solubility than BDT(ThBTTh)2. However, the integration of additional alkyl side chains sacrifices its optoelectronic performance and the sacrifice extent is highly dependent on their attaching fashions. The molecule SM2 having new additional side chains in two inner thiophene units displayed much better performance (hole mobility: 1.80 × 10−2 cm2 V-1 s-1, solar cell efficiency: (2.57 ± 0.17)%) than SM1 that integrates them at the two terminal thiophene units (hole mobility: 2.18 × 10−4 cm2 V-1 s-1, solar cell efficiency: (0.87 ± 0.11)%). For understanding the origination of such performance differences, detail characterizations including differential scanning calorimetry, ultraviolet–visible absorption spectroscopy, cyclic voltammetry, density function theoretical calculation, X-ray diffraction and atomic force microscopy have been carried out. Finally, benefiting from their enhanced good solubility in non-chlorinated solvents, toluene has been proved capable as a green processing solvent for organic solar cell fabrication. The so-obtained SM2 devices displayed an optimized efficiency of (2.35 ± 0.19)%.

The continuous microstructure evolution occurring in active layers of polymer-fullerene solar cells is one of the main causes for their device instability. With aim to tackle it, this work developed a new polymerizable fullerene acceptor, [6,6]-phenyl-C 61 -butyl acrylate (PC 61 BA). It was found that PC 61 BA has similar light-absorption properties and HOMO and LUMO energy levels as [6,6]-phenyl-C 61 -butyric acid methyl ester (PC 61 BM), and can be converted into insoluble oligomers upon heating at 150 °C. Polymer-fullerene solar cells using poly(3-hexylthiophene) (P3HT) as donor and PC 61 BA as acceptor exhibited an optimized efficiency of 3.54%, the performance comparable to P3HT/PC 61 BM cells (optimized efficiency: 3.70%). But, the former possess much better thermal stability than the latter owing to aggregation suppression by the polymerized PC 61 BA. These results indicate that PC 61 BA, unlike most previous reported, is a unique polymerizable fullerene derivative that can be used alone as acceptor to achieve both efficient and thermally stable polymer solar cells.

Systematic studies on a family of photovoltaic molecules are important for fundamentally understanding the basic principles and the key structural factors that govern their photovoltaic performance. In this work, a series of D2-A-D1-A-D2 type small molecules with isoindigo as acceptor (A), oligothiophene as donor (D1), and 5-hexyl thiophene as D2 were designed, synthesized and studied. The number of thiophene unit in oligothiophene segment is systematically varied from 0 to 4. It has been found this structural parameter have significant influence on their phase transition behaviours, light absorption properties, frontier orbital energy levels, molecular packing structures in both neat and blending films with [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM), charge mobility, phase separation morphology, and as well as photovoltaic performances. The compounds bearing odd number of thiophene unit displayed much better photovoltaic performance than those having even number, while the best performance was given by that having terthiophene as D1 unit.

Three donor–acceptor (D–A) conjugated molecules using hexa-peri-hexabenzocoronene (HBC) as D unit while benzo[2,1,3]thiadiazole (BT) as A unit have been synthesized. They have different D–A combination fashions, including D–A, A–D–A and D–A–D. Their thermal, optical, electrochemical properties and molecular interactions have been thoroughly studied, with particular attention paid on the effect of different D–A combinations. Property comparison reveals that the ADA molecule using HBC as core and two BT units as arms possesses a better light absorption property and a more ordered film structure than the other two. Finally, such ADA molecule displayed the best field-effect transistor and photovoltaic performances.

Different from the well-studied photovoltaic conjugated polymers and small molecular compounds, poly(rod-coil) polymers are emerging as a new class of photovoltaic materials. Since they are composed of definite conjugated and non-conjugated segments in an alternative fashion, this kind of material is expected to merge the merits from both small molecular compounds and conjugated polymers. Based on benzodithiophene-centered acceptor–donor–acceptor (A–D–A) conjugated segments and dicarboxylate-linked alkyl non-conjugated segments, this study has newly designed and synthesized two poly(rod-coil) polymers. Together with three previously reported analogues, these polymers have been systematically investigated for their photovoltaic performances, with special attention paid to the effect of the dicarboxylate linking unit in non-conjugated segments and the alkyl side chains on rigid conjugated segments. It was found that the former factor has a small influence, while the latter has a significant impact on most film-related properties of the material, including film absorption spectrum, frontier orbital energy levels, bandgap, microstructure and morphology of pristine and photovoltaic blend films, as well as hole mobility. After optimization, bulk heterojunction organic solar cells based on this series of polymers reported power conversion efficiencies in range of 0.4-1.09%.

This paper reported a facile strategy to the large scale synthesis of multi-responsive core–shell microgels via seed miniemulsion copolymerization of N-vinylcaprolactam (NVCL) and acrylonitrile (AN) using 2,2′-azobis(2-methylpropionitrile) (AIBN) and divinylbenzene (DVB) as the initiator and the cross-linker, respectively. The core–shell microspheres were initially prepared via miniemulsion polymerization with polyacrylonitrile (PAN) as the core and poly(N-vinylcaprolactam) (PNVCL) as the shell. Then P(NVCL-co-AA) microgels were obtained by hydrolysis of the PAN core under base conditions. The sizes, morphologies and swelling behavior of the as-obtained microparticles were systematically investigated by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analyses (TGA). The results showed that the obtained microgels were spherical in shape with an average size of about 100 nm. P(NVCL-co-AA) microgels had a core–shell morphology with PAA as the core and PNVCL as the shell. The contents of NVCL and DVB had an effect on the structure of microgels and hydrodynamic diameters, respectively. The resultant microgels can reversibly swell and shrink in response to pH and temperature variation, demonstrating great promise for potential applications in drug delivery and bio-sensors.

The formation of high quality homogeneous active component films is essential to the fabrication of many organic optoelectronic devices, especially those having a large area module. However, most small molecule (SM) semiconductors are unable to achieve such a goal via solution processing because their large and rigid π-conjugated structures generally drive them to aggregate or crystallize into inhomogeneous domains in the process. In this work, a SM semiconductor (SM-DPP6T) based on a diketopyrrolopyrrole (DPP) center with three thiophene units on both sides encounters the same problem. However, when its molecules are interconnected with soft alkyl linkers and change into a poly(rod-coil) polymer, PRC-DPP6T, the problem is solved. Compared with SM-DPP6T, PRC-DPP6T can form a high quality homogeneous film with much better uniformity and coverage on silicon wafers by spin-coating. Moreover, the so-prepared PRC-DPP6T field-effect transistors displayed a much narrower performance distribution and comparable mobility when compared with those based on SM-DPP6T (0.17 vs. 0.15 cm2 V−1 s−1). These results demonstrate that the interconnection of SM semiconductor molecules with soft non-conjugated linkers is a promising way to improve film formation quality while keeping mobility intact.

Headspace gases from cores are sampled in the gas hydrate drilling well DK-8 in the Qilian Mountain permafrost. Gas components and carbon isotopes of methane from headspace gas samples are analyzed. The geochemical features of the headspace gases along the well profile are compared with occurrences of gas hydrate, and with the distribution of faults or fractures. Their geochemical significance is finally pointed out in gas hydrate occurrences and hydrocarbon migration. Results show high levels of hydrocarbon concentrations in the headspace gases at depths of 149–167 m, 228–299 m, 321–337 m and 360–380 m. Visible gas hydrate and its associated anomalies occur at 149–167 m and 228–299 m; the occurrence of high gas concentrations in core headspace gases was correlated to gas hydrate occurrences and their associated anomalies, especially in the shallow layers. Gas compositions, gas ratios of C 1 /ΣC 1–5 , C 1 /(C 2 + C 3 ), iC 4 /nC 4 , and iC 5 /nC 5 , and carbon isotopic compositions of methane (δ 13 C 1 , PDB‰) indicate that the headspace gases are mainly thermogenic, partly mixed with biodegraded thermogenic sources with small amounts derived from microbial sources. Faults or fracture zones are identified at intervals of 149–167 m, 228–299 m, 321–337 m, and near 360–380 m; significantly higher gas concentrations and lower dryness ratio were found in the headspace gases within the fault or fracture zones compared with areas above these zones. In the shallow zones, low dryness ratios were observed in headspace gases in zones where gas hydrate and faults or fracture zones were found, suggesting that faults or fracture zones serve as migration paths for gases in the deep layers and provide accumulation space for gas hydrate in the shallow layers of the Qilian Mountain permafrost.

This communication presents a facile and large-scale fabrication of poly(acrylic acid) (PAA) hollow nanogels via an in situ Pickering miniemulsion polymerization method. Cross-linked polyacrylonitrile (PAN) nanoparticles with a hollow structure were prepared by using a hydrophobic solvent as the liquid core. The complete hydrolysis reaction process of the PAN shell leads to the successful formation of hollow PAA nanogels. Furthermore, magnetic hollow microgels are obtained conveniently.

This article provides a facile method for the large-scale preparation of magnetic poly(acrylic acid) (PAA) nanogels. Cross-linked polyacrylonitrile (PAN) nanoparticles were synthesized via a miniemulsion polymerization method using acrylonitrile (AN) and divinyl benzene (DVB) as the raw materials, and then PAA nanogels were obtained from the cross-linked PAN nanoparticles under basic conditions. The structure and morphologies of PAN nanoparticles, PAA nanogels, and magnetic PAA nanogels were characterized by Fourier-transformed infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and dynamic light scattering equipment (DLS), respectively. The pH-responsive property of PAA nanogels was investigated by measuring their swelling–deswelling behavior under different pH buffer solutions. The results showed that the obtained PAN nanoparticles were of uniform spherical morphology with a wrinkled surface and had a narrow size distribution with an average size of 105 nm in diameter. PAA nanogels were regular spherical particles with an average particle size of 230 nm in diameter. The PAA nanogels demonstrated excellent pH-responsive properties in different pH buffer solutions. After the addition of γ-(trimethoxysilyl)propyl methacrylate (MPS) modified magnetic nanoparticles, magnetic PAA microgels were fabricated successfully.

The composition and isotope ratio of gases from gas hydrate and organic geochemistry of mudstone, oil shale, and coal within a gas hydrate-bearing interval in the Qilian Mountain permafrost suggest that gases from gas hydrate are derived from the deep, but the lithology and burial depth of source rocks for gases from gas hydrate are not yet known. In this study, samples of mudstone, oil shale, and coal were analyzed with thermal stimulation within the gas hydrate-bearing interval in the Qilian Mountain permafrost. Results showed that gas composition and carbon isotopes of hydrocarbon gases thermally stimulated from mudstone at temperatures of 350–400 °C and from oil shale at temperatures of 380–400 °C are similar to those of gases from gas hydrate, indicating that the deep mudstone and oil shale are potential source rocks for gases from gas hydrate. The gas composition of hydrocarbon gases thermally stimulated from coal was similar to that of gas hydrate, but their carbon isotope values were very differen...

Gas source for gas hydrate is not clear yet in the Muli of Qilian Mountain permafrost. In this paper a case is illustrated in the hole of DK-2 during gas hydrate drilling; gas composition and isotopes of gas hydrate and its associated gases are analyzed; organic geochemistry on mudstone, oily shale, coal, oil & gas indications are correlated within the interval of gas hydrate occurrences; the aim is to discuss the source of gases from gas hydrate and its implication to gas hydrate exploration in the study area. Results from gas composition and isotopes of gas hydrate and its associated gases reveal that the origin of gases from gas hydrate is mainly concomitant with deep oil or crude oil in the study area. Parameters for the abundance, type and thermal evolution of organic matter in mudstone, oil shale, coal in the same interval of gas hydrate occurrence suggest that these strata, especially within gas hydrate stability zone, play little role in gas sources for gas hydrate. Reservoir pyrolysis results for oil & gas indication-bearing cores reveal that oil & gas indications are closely associated with gas hydrate within its interval, indicating that they may serve as a sign of gas hydrate in the study area.

Four scientific experimental wells were drilled in the Qilian Mountain permafrost of Qinghai Province, China, in 2008 and 2009. Gas hydrate was obtained from three of four wells and its related anomalous phenomena were observed in all the four wells. Raman spectroscopy was used in the laboratory to evaluate the type of clathrates recovered from these sites, including structures containing large and small cages of hydrocarbon gases. Gas hydrate and associated anomalies occur mainly in fractured mudstone, oily shale, siltstone, and fine-grained sandstone. Secondary occurrences were also present in the pore space of fine to medium grained sandstone in a zone between 133 and 396 mbs. This interval was vertically discontinuous and horizontally did not appear to correlate between wells. Gas hydrate occurrences in these wells are not solely related to lithology and are strongly controlled by fissures in the Qilian Mountain permafrost. Gas geochemical characteristics reveal that gas hydrate is primarily composed of CH4, with secondary components of C2H6, C3H8, and CO2. Raman spectra analysis indicates a sII gas hydrate structure. Gas composition and carbon and hydrogen isotope geochemistry show that gases from gas hydrate are mainly thermogenic with a biogenic fraction. In the study area, gas hydrate and its related anomalous phenomena are confined to the gas hydrate stability zone which is constrained by permafrost pressure and temperature conditions. Core observations indicate that individual gas hydrate occurrences are controlled by fissures. It is speculated that, when hydrocarbon gases reach the gas hydrate stability zone, they form into gas hydrate that occurred preferably in fissures beneath the permafrost.

Three arylamide-bridged biscoumarin derivatives 1–3 have been designed and prepared. Compounds 1 and 2 are induced by the intramolecular N-H…O and N-H…F hydrogen bonding to possess a helical conformation, and 3 is induced to have an extended conformation. A comparison of their absorption and fluorescent spectra in a variety of solvents of a wide range of polarity with those of control compound 4 reveals that, for foldamers 1 and 2, the intramolecular hydrogen bonding and the helical conformations exist in most solvents, but do not exist or are very weak in DMF and DMSO.

Poly(tetrahydrofuran) (PTHF) reacted with toluene diisocyanate (TDI) to form a prepolymer. Such a prepolymer was extended by 2,2-hydroxymethyl butanoic acid (DMBA) to form a segmented polyurethane with carboxyl (PUc) consisting of alternating soft and hard segments, where carboxyls are distributed only along the hard segments. By using static and dynamic laser light scattering (LLS) as well as atomic force microscopy (AFM), we have investigated the self-assembly of the PUc and poly(4-vinylpyridine) (P4VP) in tetrahydrofuran/chloroform mixed solvent. Our experiments show that the PUc and P4VP form a stable assembly with a size of 59–122 nm due to the H-bonding, depending upon the PUc (COOH) concentration. The LLS and AFM measurements demonstrate the assembly is spherical.

Conjugated extension of an organic optoelectronic moiety along different directions is of significance for exploring its usage in material design and understanding its structure-property relationships. In this work, three benzo[1,2-b:4,5-b']dithiophene-cored molecules were designed and synthesized by attaching donor-acceptor conjugated arms composed of thiophene and benzothiadiazole via the direction of its 2,6-position (horizontal), 4,8-position (vertical), and the both (cross), respectively. Compared with vertical linkage, the horizontal modification benefits the achievement of a red-shifted and wider absorption spectrum, a narrow bandgap and a more regular crystalline property, but a higher highest occupied molecular orbital (HOMO) energy level. Cross-shaped compound exhibits both a wide absorption spectrum and large absorption coefficients, and thus gave the largest short-circuit current density for its solar cell among three so-prepared devices.