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Recently, heteroatom-doped three-dimensional (3D) nanostructured carbon materials have attracted immense interest because of their great potential in various applications. Hence, it is highly desirable to exploit a simple, renewable, scalable, multifunctional, and general strategy to engineer 3D heteroatom-doped carbon nanomaterials. Herein, a simple, eco-friendly, general, and effective way to fabricate 3D heteroatom-doped carbon nanofiber networks on a large scale is reported. Using this method, 3D P-doped, N,P-co-doped, and B,P-co-doped carbon nanofiber networks are successfully fabricated by the pyrolysis of bacterial cellulose immersed in H3PO4, NH4H2PO4, and H3BO3/H3PO4 aqueous solution, respectively. Moreover, the as-prepared N,P-co-doped carbon nanofibers exhibit good supercapacitive performance.

A new kind of high-performance asymmetric supercapacitor is designed with pyrolyzed bacterial cellulose (p-BC)-coated MnO₂ as a positive electrode material and nitrogen-doped p-BC as a negative electrode material via an easy, efficient, large-scale, and green fabrication approach. The optimal asymmetric device possesses an excellent supercapacitive behavior with quite high energy and power density.

Hydrogels and aerogels are two typical families of gels, classified according to the medium they encompass, that is, water and air, respectively. Hydrogels have not only pervaded our everyday life in a variety of forms (e.g., fruit jellies, toothpaste, contact lenses, and hair gel), but have also been extensively explored as functional soft materials for use in various scientific fields. Replacing the liquid solvent in hydrogels or other wet gels by air without collapsing the network structure can lead to a new type of porous materials, namely, aerogels. Particularly, 3D nanoscale networks with open pores in the gels allow access and fast diffusion of ions and molecules, and thus hydrogels/aerogels have exhibited excellent performance as super adsorbents, electrode materials for batteries and supercapacitors, catalyst supports, and chemical and biological sensors. Despite their outstanding potential, several challenges in aerogel synthesis still must be addressed prior to their extensive practical application. The major problem associated with conventional aerogels is poor mechanical stability. The mechanical strength of aerogels could be enhanced by nanocasting conformal polymer coatings on preformed 3D networks, but this was accompanied by dramatic decreases in their porosity. Furthermore, to prevent the network from collapsing in a gel, supercritical drying is the most widely used technique for solvent removal. It is difficult to prepare low-cost aerogels on a large scale due to the limitations of industrial supercritical drying. Although several nanomaterials including carbon nanotubes, cellulose nanofibers, and the newly discovered graphene have been recently used as building blocks and assembled into monolithic gels, there is a lack of precise control of their physicochemical properties, particularly the size of building blocks, the porosity, and their surface chemistry, which are crucial in the further design and functionalization of aerogels for various applications. Here we report a new class of monolithic hydrogels/aerogels consisting of highly uniform carbonaceous nanofibers (CNFs), based on the recent, well-developed templatedirected hydrothermal carbonization (HTC) process. Compared with the conventional process for aerogel preparation, our synthetic method has some significant advantages: 1) Direct scaleup from 30 mL to 12 L just by using a large autoclave and without changing reactant concentrations and reaction time; 2) Easy and precise control of the structural parameters and mechanical strength of the CNF hydrogels/ aerogels over a wide range; and 3) Extraordinary flexibility and high chemical reactivity of the CNF gels give them great application potential. The synthesis of CNF gels is illustrated in Figure 1a. Ultrathin Te nanowire (TeNWs) templates are first dispersed in glucose solution to form a homogenous mixture (step 1 in Figure 1a). Hydrothermal treatment of the mixture at 180 8C for 12–48 h results in a mechanically robust monolithic gel-like product, which occupies the whole Teflon container and can be taken out directly without any damage (step 2 in Figure 1a; see also Supporting Information Figure S1a). The as-prepared wet gel can be easily cut into the desired shape (Supporting Information Figure S1b). After washing and chemical etching to remove TeNWs (Supporting Information Figure S2), the CNF hydrogel is formed (step 3 in Figure 1a). To obtain the CNF aerogel, water in the hydrogel is removed by freeze-drying (step 4 in Figure 1a and Supporting Information Figure S1c). A low-magnification SEM image of the aerogel reveals a highly porous network structure consisting of disordered nanofibers with uniform size (Figure 1c, left). There is no apparent difference in CNF size and distribution over the whole monolithic gel (Supporting Information Figure S3), that is, the network structure is homogeneous. Further SEM observations indicate that these highly uniform nanofibers interconnect with each other to a high degree through numerous junctions (Figure 1c, right). We hypothesize that these junctions are responsible for the outstanding mechanical properties of the gels. Formation of junctions between CNFs is not difficult to understand. In the original mixture before hydrothermal treatment, it was unavoidable that the TeNWs physically contacted or approached each other if their concentration reached a critical [*] Dr. H. W. Liang, Q. F. Guan, L. F. Chen, Z. Zhu, W. J. Zhang, Prof. S. H. Yu Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemistry, National Synchrotron Radiation Laboratory, University of Science and Technology of China Hefei, Anhui 230026 (China) E-mail: shyu@ustc.edu.cn Homepage: http://staff.ustc.edu.cn/~ yulab/

The removal of dye and toxic ionic pollutants from water is an extremely important issue. A simple filtration process to decontaminate water by employing a free-standing fibrous membrane fabricated from highly uniform carbonaceous nanofibers (CNFs) is demonstrated. This process combines the excellent adsorption behavior of CNFs and the advantages of membrane filtration over conventional adsorption techniques, which include simple scale-up, reduced time, and lower energy consumption. Batch adsorption experiments showed that the CNFs exhibited larger adsorption capacities than commercial granular active carbon (GAC) and carbon nanotubes (CNTs) because of their large surface area, high uniformity, and numerous active sites on the surface of nanofibers. Membrane filtration experiments proved that the CNF membranes could remove methylene blue (MB) efficiently at a very high flux of 1580 L m−2 h−1, which is 10–100 times higher than that of commercial nano- or ultrafiltration membranes with similar rejection properties. The high permeability of CNF membrane permits stacking of membranes to improve adsorption capacity. In addition, the CNF membranes are easily regenerated and remain unaltered in adsorption performance over six successive cycles of dye adsorption, desorption, and washing. Given the high adsorption and regenerability performance of the CNF membrane, it should have potential applications in water purification.

A new catalyst for the oxygen reduction reaction in fuel cells and metal—air batteries is prepared from aqueous solutions of carbonaceous nanofibers, pyrrole, and FeCl3 (room temperature, 4 h, followed by pyrolysis under flowing N2).

Objectives To present the prenatal diagnosis of de novo distal 11q deletions and a review of the literature. Clinical Subjects and Methods A 31-year-old primigravid woman underwent amniocentesis at 20 weeks' gestation because of a maternal serum alpha-fetoprotein (MSAFP) level of 2.63 multiples of the median. Amniocentesis demonstrated a karyotype of 46,XY,del(11)(q24.2). The parental karyotypes were normal. Level II ultrasound revealed short femurs and humeri, and overlapping of the toes. Postnatally, the proband manifested additional findings of the characteristic facial dysmorphism and camptodactyly. A 38-year-old gravida 2, para 1, woman underwent amniocentesis at 18 weeks' gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 46,XX,del(11)(q24.1). The parental karyotypes were normal. Level II ultrasound did not show fetal structural abnormalities. Postnatally, the proband manifested characteristic facial dysmorphism and camptodactyly. Results Of these two cases, genetic marker analysis determined the paternally derived distal deletions of chromosome 11q and the deletion breakpoints. A comparison of the present cases with the reported cases of prenatally diagnosed distal 11q deletion is made. Conclusion The distal 11q deletion can be identified prenatally because of parental balanced translocations involving chromosome 11, previous-term infants with an unbalanced rearrangement, advanced parental age, sonographically detected fetal abnormalities and abnormal maternal serum screening. Fetuses with de novo distal 11q deletions may be associated with elevated MSAFP and abnormal sonographic findings of the digits and limbs in the second trimester. Copyright © 2004 John Wiley & Sons, Ltd.

As a youthful family of crystalline porous materials, metal–organic frameworks (MOFs), assembled by inorganic vertices (metal ions or clusters) and organic ligands, feature ultrahigh porosity, high surface area, and synthetic and structural tailorability, along with relatively easy synthesis, making them excellent candidates for a large number of applications. Recently, increasing research interest in the electrochemical fields with regard to the environment and energy has been received. Lots of MOFs have been designed, prepared, and used in electrochemical applications, exhibiting fascinating performances. Here, the rational fabrication of electrochemical-application-directed functional MOFs and MOF composites is appraised. The synthetic strategies for the enhancement of corresponding MOF electrochemical behaviors are summarized and the relationship between structure and electrochemical performance is discussed. It is expected that the summary will be helpful for the future development of related MOFs and MOF composites with an excellent electrochemical performance.

The development of high-performance electrochemical energy storage devices is critical for addressing energy crises and environmental pollution. Hence, the design and preparation of next-generation electrode materials have been gaining increasing attention. Recent progress has demonstrated that three-dimensional (3D) carbon nanomaterials are extremely promising candidates for the electrodes of electrochemical energy storage devices due to their unique structural advantages of interlinked architecture. Herein, recent advances in the scalable fabrication of 3D carbon nanofiber (CNF)-based materials and their applications for electrochemical energy storage devices are summarized. Some representational 3D CNF architectures, such as CNF gels, 3D CNF films, 3D CNF arrays, and their nanocomposites, are highlighted with regard to various applications, including supercapacitors, lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), lithium–sulfur (Li–S), lithium–selenium (Li–Se), and metal–O2 batteries, as well as other new battery systems. Finally, contemporary challenges in the scalable fabrication of 3D CNF architectures are outlined and a brief outlook to future studies is given. This review illustrates significant opportunities for the macroscopic fabrication of 3D CNF architectures, and therefore inspires new discoveries to promote the practical applications of 3D CNF architectures in electrochemical energy storage fields.

We report on the prenatal diagnosis, genetic analysis and clinical manifestations of a 49,XXXXY fetus. A 31-year-old, primigravida woman was referred for genetic counselling at 17 weeks' gestation with the sonographic findings of intrauterine growth retardation, generalized oedema, a large septated cystic hygroma colli measuring 5×4 cm, and abnormal posturing of the lower extremities. Quantitative fluorescent polymerase chain reaction (QF-PCR) with small tandem repeat (STR) markers specific for chromosome X and a pentanucleotide marker X22 for the Xq/Yq pseudoautosomal region PAR2 rapidly detected the X-chromosome polysomy from amniotic fluid cells. This abnormality appeared to arise from successive non-disjunction during maternal meiosis I and meiosis II. Cytogenetic analysis revealed a karyotype of 49,XXXXY. Our case shows that a 49,XXXXY fetus in the second trimester may demonstrate hydrops fetalis and a large septated cystic hygroma colli by prenatal ultrasound. Our case also shows that QF-PCR assays with sex chromosome specific STR markers provide rapid prenatal diagnosis of numerical sex chromosome aneuploidy as well as its genetic cause in fetal cystic hygroma. Copyright © 2000 John Wiley & Sons, Ltd.

Prenatal diagnosis of simultaneous occurrence of double trisomy involving chromosomes 18 and X is extremely rare. We report on the prenatal diagnosis, genetic analysis and clinical manifestations of a fetus with both trisomy 18 and trisomy X. A 26-year-old, para 1 woman was referred for genetic counselling at 36 weeks' gestation with the sonographic findings of intrauterine growth retardation (IUGR), polyhydramnios, ventricular septal defect, and an enlarged cisterna magna. Both cordocentesis and amniocentesis revealed a consistent karyotype of 48,XXX,+18. Quantitative fluorescent polymerase chain reaction using polymorphic small tandem repeat markers specific for chromosomes 18 and X rapidly determined that both aneuploidies arose as a result of non-disjunction in maternal meiosis II. Our case shows that two non-disjunction events can occur not only in the same parent, but also in the same cell division. Our case also shows that double trisomy, 48,XXX,+18, can demonstrate an enlarged cisterna magna, IUGR and polyhydramnios in prenatal ultrasound.

De novo interstitial 16q deletion diagnosed in utero has not previously been reported. We present a case of fetal de novo interstitial 16q deletion associated with the sonographic findings of prominent coronal sutures, a prominent frontal bone, and shortening of the long bones. Genetic amniocentesis at 23 weeks' gestation revealed a de novo deletion of 16q13-q22. At birth, the fetus manifested a dysmorphic phenotype correlated with monosomy 16q syndrome. Linkage analysis of the family confirmed the maternal origin and the extent of the deletion. We suggest that prenatal detection of a prominent frontal bone with prominent cranial sutures and shortening of the long bones should prompt cytogenetic analysis looking for a deletion in the long arm of chromosome 16.

We report on the prenatal diagnosis, genetic studies, and pathology of a case with de novo isochromosome 13q. A 31-year-old primigravida was referred for genetic counselling at 26 weeks' gestation due to the sonographic findings of intrauterine growth retardation and microcephaly. Level II ultrasonograms further demonstrated alobar holoprosencephaly, hypotelorism, polydactyly, a ventricular septal defect, and a single nostril. A diagnosis of cebocephaly was made. Genetic amniocentesis and cord blood sampling revealed translocation trisomy 13 with a de novo t(13q13q) rearrangement. Chromosomal analysis using G- and C-banding techniques and fluorescence in situ hybridization (FISH) showed an apparent monocentric isochromosome. Molecular analyses using polymorphic molecular markers showed that the rearrangement was consistent with an isochromosome of maternal chromosome 13q[46,XX,i(13)(q10)]. Necropsy confirmed cebocephaly and the prenatally detected anomalies.

Free radical melt grafting of glycidyl methacrylate (GMA) onto polypropylene (PP) was studied. The extent of GMA grafting and the molecular weight of the functionalized PP copolymers were controlled by carefully manipulating various reaction factors, such as monomer concentration, initiator concentration, reaction temperature, and molecular weight of the starting PP homopolymer. The use of a second monomer, styrene, in the grafting process helped to increase GMA grafting further and reduce chain scission. The GMA modified PP copolymer was found to be able to reactively compatibilize PP/acrylonitrile-co-butadiene-co-acrylic acid rubber (NBR) blends. Up to an eight-fold increase in the impact energy of the PP/NBR blend was obtained. The compatibilizing capacities of the reactive copolymers, in terms of impact energy improvement of the PP/NBR blend, were found not to be exclusively dependent on the total concentration of reactive functionalities in the matrix of the blend. The characteristics of the reactive copolymers, i.e., the extent of functionalization and the molecular weight, were found to have significant influences on the compatibilizing capacity. A large amount of moderately functionalized copolymer offers better compatibilization performance than a small amount of highly functionalized copolymer. A significant drop in impact energy was observed with declining molecular weight of the copolymer.

Distal 10q trisomy is a well-defined but rare syndrome. Most cases are diagnosed in infancy or in childhood and rarely include prenatal findings. We present a case of fetal distal 10q trisomy with abnormal prenatal sonographic findings. A 19-year-old primigravida was referred for genetic counselling at 18 gestational weeks because her husband had a familial history of congenital anomalies. Genetic amniocentesis was thus performed and showed fetal distal 10q trisomy (10q24.1-->qter), 46,XX,der(22)t(10;22)(q24.1;p11.2)pat, resulting from paternal t(10;22) reciprocal translocation. Level II ultrasonograms further demonstrated bilateral hydronephrosis, ventricular septal defect and facial dysmorphism ascertained by three-dimensional ultrasound. The pregnancy was terminated at 22 gestational weeks. Post-mortem autopsy confirmed the sonographic findings. We suggest that abnormal prenatal sonographic findings such as cardio-vascular, renal and facial malformations should alert cytogeneticists to search for subtle chromosomal abnormalities.